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PLOS Neglected Tropical Diseases logoLink to PLOS Neglected Tropical Diseases
. 2022 Oct 14;16(10):e0010861. doi: 10.1371/journal.pntd.0010861

The epidemiology and disease burden of congenital TORCH infections among hospitalized children in China: A national cross-sectional study

Linlin Zhang 1,2, Xinyu Wang 3, Mengjia Liu 1,2, Guoshuang Feng 3, Yueping Zeng 4, Ran Wang 1,2,*, Zhengde Xie 1,2,*
Editor: Winsley Rose5
PMCID: PMC9604879  PMID: 36240247

Abstract

Background

Congenital TORCH (Toxoplasma gondii (T. gondii), rubella virus (RV), cytomegalovirus (CMV), and herpes simplex virus (HSV)) infections are associated with a variety of adverse prenatal and neonatal events, including miscarriage, malformations and developmental abnormalities, and they remain an issue that cannot be neglected in China. However, the current research focuses more on the general screening of TORCH in women of childbearing age, and the medical information of children hospitalized due to congenital and perinatal TORCH infections has not been described in detail. This study summarized and analyzed the epidemiological characteristics, clinical manifestations, length of stay (LOS), and the disease burden of hospitalized children diagnosed with congenital TORCH infections in 27 children’s hospitals in China.

Methodology

Based on the face sheet of discharge medical records (FSMRs) of hospitalized children in 27 tertiary children’s hospitals collected in the Futang Research Center of Pediatric Development and aggregated into FUTang Update medical REcords (FUTURE), we summarized and analyzed the epidemiological characteristics, clinical manifestations, LOS, the disease burden (in US dollars, USD) and potential risk factors for hospitalized children diagnosed with congenital toxoplasmosis, congenital rubella syndrome, congenital cytomegalovirus infection, and congenital HSV in 27 children’s hospitals in China from 2015 to 2020.

Results

One hundred seventy-three patients aged 0–<1 year were hospitalized for congenital TORCH infections. Among infections with TORCH, hospitalization with congenital toxoplasmosis was the least common, with only five cases were reported (2.89%), while the LOS was the highest. The proportion of patients with congenital rubella syndrome (CRS) was 15.61%, and 86% of children hospitalized with CRS had cardiovascular malformations, and the economic burden was the highest. Congenital CMV infection cases accounted for the largest proportion (76.30%). Overall, 5.20% of patients were infected with HSV, and the expense of hospitalization for congenital HSV infection was relatively low.

Conclusion

In the present study, the hospitalization proportion due to congenital TORCH infection was extremely low (17.56 per 100,000 neonates), indicating that China’s congenital TORCH infection prevention and control policies remain effective. The lowest proportion of patients was hospitalized with congenital toxoplasmosis, while the LOS was the longest. The economic burden of CRS was heavy, and infants are recommended be vaccinated against RV in a timely manner. Congenital CMV infections accounted for the largest proportion of patients, suggesting that the disease burden of congenital CMV infection cannot be ignored, and the prevention of congenital CMV infection during pregnancy is still an important issue that needs to pay attention. The expense of hospitalization for congenital HSV infection was relatively low, while the disease burden increases significantly when patients develop complications. These data illustrate the importance of improving screening for congenital TORCH infections in the early diagnosis and treatment of neonatal patients.

Author summary

Congenital TORCH (T. gondii, RV, CMV, and HSV) infections are associated with a variety of adverse prenatal and neonatal events, including miscarriage, malformations, and developmental abnormalities. Congenital TORCH infections remain an issue that cannot be neglected in China. However, the current research focuses more on the general screening of TORCH in women of childbearing age, and the medical information from children hospitalized due to congenital TORCH infections has not been described in detail. This study summarized and analyzed the epidemiological characteristics, clinical manifestations, length of stay (LOS), and disease burden of hospitalized children diagnosed with congenital toxoplasmosis, congenital rubella syndrome (CRS), congenital cytomegalovirus infection, and congenital herpes simplex virus infection in 27 children’s hospitals in China from December, 2015 to December, 2020 based on the FUTang Update medical Records (FUTURE). A total of 173 patients were hospitalized for congenital TORCH infections. The hospitalization rate due to congenital TORCH infection was extremely low (17.56 per 100,000 neonates), showing that China’s congenital TORCH infection prevention and control policies remain effective. Hospitalization due to congenital toxoplasmosis was the least common, with only five cases reported (2.89%). The economic burden of CRS was heavy, and infants are recommended be vaccinated against RV in a timely manner. Congenital CMV infections accounted for the largest proportion of cases, suggesting that the disease burden of congenital CMV infection cannot be ignored, and the prevention of congenital CMV infection during pregnancy is still an important issue that needs to pay attention. The hospitalization expense of congenital HSV infection was relatively low, while the disease burden increases significantly when patients develop complications. These data illustrate the importance of improving screening for congenital TORCH infections in the early diagnosis and treatment of neonatal patients. A complete understanding of the epidemiology and disease burden of congenital TORCH infections is essential for reducing the incidence of adverse pregnancy outcomes.

Introduction

The acronym ‘TORCH’ was introduced by Nahmias in 1971 to underline a group of pathogens that cause congenital and perinatal infections: Toxoplasma gondii (T. gondii), rubella virus (RV), cytomegalovirus (CMV), and herpes simplex virus (HSV) [1]. Congenital TORCH infections are significant cause of prenatal and neonatal abnormalities and deaths. Apart from miscarriage, stillbirths, and neonatal deaths, congenital TORCH infections account for 2% to 3% of all congenital anomalies [2].

T. gondii is the only zoonotic protozoan parasite among TORCH pathogens. Toxoplasma infection usually occurs through contact with feces of infected cats or consumption of food or water contaminated with the parasite. T. gondii infection has a wide distribution, and the estimated global incidence of congenital toxoplasmosis is approximately 190,100 cases annually, with an incidence rate of approximately 1.5 cases per 1,000 live births [3]. Infection with T. gondii during pregnancy results in severe fetal damage including hydrocephalus, intracerebral calcifications, mental retardation, chorioretinitis, and death [4]. Studies have reported that 29.8% of congenital toxoplasmosis cases might result in eye damage [5], and the disease burden caused by this disease must not be overlooked.

Primary RV infection in the early stages of pregnancy may lead to serious birth defects known as congenital rubella syndrome (CRS). Congenital heart defects (such as patent ductus arteriosus and branch pulmonary artery hypoplasia/ stenosis), cataracts, and sensorineural hearing loss are the classic triad. The WHO estimates that approximately 100,000 congenital rubella syndrome cases occur per year [6, 7]. RV is a teratogenic virus, and the fetus teratogenic rate reaches 10–30%, which places a heavy economic and social burden on the family and society [8]. Since the inclusion of rubella in the China Expanded Programme on Immunization (EPI) system in 2008, the incidence of rubella has decreased from 91.00 per million in 2008 to 2.83 per million in 2018 [9]. However, there were some studies reported that the seropositivity of anti-rubella IgG antibodies in 8-month-old infants was only 3.33–4.6% in several regions of China. Thus, the protection of maternally transferred antibodies is still insufficient, and studies of the epidemiology and disease burden of CRS in neonates are necessary.

CMV is currently recognized as the most common virus causing intrauterine infection, with a reported global prevalence of congenital CMV infection of approximately 0.2% to 2% [10]. China is the high-incidence area for CMV infection. A study found that the positive rate of CMV-IgM in newborns and infants in Qingdao, China was 0.67%, and the positive rate of IgG was 96.28% [11]. Infants with symptomatic congenital CMV infection are at significantly increased risk of developing adverse long-term outcomes, the most common manifestations are jaundice, congenital malformations, and liver damage, and other clinical manifestations include premature birth, central nervous system involvement, neuroimaging anomalies chorioretinitis, and sensorineural hearing loss [12]. Congenital CMV infection seriously endangers the health and safety of children.

Vertical transmission is one of the main transmission routes of congenital HSV infection. An estimated 1/3,200 live births are infected with HSV [13]. Eighty percent of infants with the disseminated disease die without treatment, and those who survive tend to have severe brain damage, which places a heavy burden on the public health system and society [14]. Ambroggio et al. estimated that hospitalization costs up to 37,431 US dollars (USD) per patient with neonatal HSV infection (interquartile range: 14,667–74,559 USD) [15]. However, due to a lack of reported data on congenital HSV infection, its disease burden is unclear in China.

The introduction of routine maternal screening for TORCH in China has substantially reduced the overall burden of infection during pregnancy and substantially reduced adverse neonatal outcomes [16]. However, congenital TORCH infections still cause substantial morbidity. Some research reported that the seroprevalence of TORCH infections in Chinese pregnant women was 6.06%, and the positive rates of TORCH-IgM and IgG in newborns were 0.78% and 99.8%, respectively [11, 17]. Congenital TORCH infection remains an issue that must not be neglected in China. However, the current research focuses more on the general serologic screening of TORCH in women of childbearing age [7, 1618]. The epidemiology and economic burden of hospitalized children due to congenital TORCH infections have not been described in detail, and few therapeutic options are available to manage these infections. The face sheet of discharge medical records (FSMRs) in the electronic medical system has generated a large amount of medical data for all patients during hospitalization, which has the value of evidence-based medicine. Based on the FUTang Update medical Records (FUTURE) [19], a national pediatric patient database in China, this study summarized and analyzed the epidemiological characteristics, clinical manifestations, length of stay (LOS), disease burden (in USD) and potential risk factors for hospitalized children diagnosed with congenital toxoplasmosis, CRS, congenital CMV infection, and congenital HSV infection in 27 children’s hospitals in China from 2015 to 2020. Understanding the epidemiology and disease burden of congenital TORCH infections among hospitalized children is important to inform the optimization of care pathways and utility newborn screening.

Methods

Ethics statement

This study was approved by the Ethics Committee of Beijing Children’s Hospital, Capital Medical University (Approval Number: [2022]-E-008-R). The requirement for informed consent of patients was waived as it only involved retrospective aggregated data analysis of medical records. Our data were fully deidentified and anonymized to protect privacy.

Data source

The Futang Research Center of Pediatric Development (FRCPD) is the first nonprofit social service organization to engage in pediatric development research under the supervision and management of the Ministry of Civil Affairs of China. The FRCPD has built a health service network system with 47 provincial children’s medical institutions as the core to strengthen the data-sharing connection among the member hospitals of the Futang Children’s Medical Development Research Center and improve the efficiency of data utilization.

FUTURE covers the face sheet of discharge medical records (FSMRs) of hospitalized children in 27 tertiary children’s hospitals in FRCPD. The FRCPD started to collect FSMRs data in December 2015, and the staff at FRCPD were responsible for checking and validating the uploaded data to control its quality and integrity.

Study design

The data analyzed in this study were retrospectively extracted from the FUTUR database for the variables of congenital toxoplasmosis, CRS, congenital CMV infection, and congenital HSV infection from 2015 to 2020. We also analyzed sociodemographic and geographic variables, admission and discharge information, primary and secondary diagnoses and hospitalization expenses of the patients. We reported the epidemiology of the cohort by calculating the total to points for the type of virus with which patients were infected and stratified them by gender, age groups, geographic regions, ethnicity, and clinical manifestation. Among them, hospitalized patients were divided into two groups according to their age (day, d, or year, y): 0–28 d (neonate) and 29 d–<1 y (infant). The 27 children’s hospitals were grouped into seven geographic regions: Northeast, North, East, South, Central, Northwest, and Southwest China [20, 21].

The eligibility of the participants and admission records

The inclusion and exclusion criteria for the participants were as follows:

  1. All included patients who were admitted with a primary diagnosis of any congenital toxoplasmosis, CRS, congenital CMV infection, or congenital HSV infection between December 1, 2015, and December 31, 2020. The 10th Revision of International Statistical Classification of Diseases and Related Health Problems (ICD-10) codes was used as the selection criteria for the primary screening and classification of disease.

  2. All included patients had a clear pathogenic and clinical diagnosis (according to the diagnostic criteria promulgated by the Health Commission of the People’s Republic of China (formerly the Ministry of Health), (http://www.nhc.gov.cn/fzs/s7852d/201512/2155fc4055ce4df687536233e1639729.shtml, http://www.nhc.gov.cn/wjw/s9492/201409/dfb9e7068025408c820e227342f7ac8b.shtml), Practical Neonatology and Expert consensus on standardized TORCH laboratory detection and clinical application (http://rs.yiigle.com/CN114452202005/1199015.htm).

  3. Patients with incomplete information for multiple vital data, such as patient gender, age, diagnosis, or burden of disease, were excluded. Patients diagnosed with other viral infections were excluded.

  4. The patients were aged ≤18 years on the index admission.

Statistical analysis

Categorical variables are described as percentages. Nonnormally distributed continuous variables are described as medians and interquartile ranges (IQRs). Differences between two groups were compared with either the chi-squared test (unordered categorical variables) or the Mann–Whitney–Wilcoxon test (ordered categorical or nonnormal-distributional continuous variables), as appropriate. The nonparametric Kruskal–Wallis test was used for comparisons among multiple groups. All statistics were analyzed using SPSS software version 22.0 (SPSS Inc., USA). Differences with p values<0.05 were considered statistically significant.

Result

Overall

According to the ICD-10 codes, we searched for hospitalizations with the first diagnosis of congenital toxoplasmosis, CRS, congenital CMV infection, and congenital HSV infection (congenital TORCH infections) under the FUTURE database. As showed in Table 1, 173 patients were hospitalized for congenital TORCH infections. Among infections with any pathogen causing TORCH, congenital CMV infection cases accounted for the largest proportion (132 cases, 76.30%), followed by CRS cases (27 cases, 15.61%), and nine cases of congenital HSV infection (5.20%). Patients hospitalized with congenital toxoplasmosis represented the lowest proportion, and only five cases were reported (2.89%).

Table 1. The general sociodemographic characteristics of pediatric patients with TORCH infections during hospitalization from December 2015 to December 2020.

Categories TORCH infections (n, %)
T. gondii RV CMV HSV
Overall (n, %) 5 (2.89) 27 (15.61) 132 (76.30) 9 (5.20)
Sex (n, %)
Male 3 (60.00) 13 (48.15) 74 (56.06) 5 (55.56)
Female 2 (40.00) 14 (51.85) 58 (43.94) 4 (44.44)
Age (n, %)
0–28 d 4 (80.00) 26 (96.30) 64 (48.48) 6 (66.67)
29 d–<1 y 1 (20.00) 1 (3.70) 68 (51.52) 3 (33.33)
Residence (n, %)
Urban 2 (40.00) 10 (37.04) 57 (43.18) 3 (33.33)
Rural 3 (60.00) 17 (62.96) 75 (56.82) 6 (66.67)
LOS [d, median (IQR)] 19 (4.5–23) 9 (5–15) 10 (6–20.75) 6 (2.5–18.5)
Expense [USD, median (IQR)] 2,162.33 (637.51–3,523.25) 2,585.45 (1,524.88–4,010.98) 1,379.00 (823.64–3,268.45) 935.03 (505.80–3,982.70)

T. gondii: Toxoplasma gondii

RV: Rubella Virus

CMV: Cytomegalovirus

HSV: Herpes Simplex Virus

LOS: length of stay

IQR: inter quartile range

USD: USA dollar

We analyzed the proportions of congenital TORCH infection-related hospitalization to total hospitalizations within different age groups of patients in the corresponding groups. As shown in Fig 1A, the proportion of hospitalizations for congenital TORCH infections was 17.56/100,000 hospitalized newborn (100/569,680) and 12.47/100,000 hospitalized infant (73/585,244). Congenital toxoplasmosis cases accounted for 0.70/100,000 hospitalized newborn (4/569,680) and 0.17/100,000 hospitalized infant (1/585,244), CRS cases accounted for 4.56/100,000 hospitalized newborn (26/569,680) and 0.17/100,000 hospitalized infant (1/585,244), congenital CMV infection cases accounted for 11.3/100,000 hospitalized newborn (64/569,680) and 11.62/100,000 hospitalized infant (68/585,244), and congenital HSV infection cases accounted for 1.05/100,000 hospitalized newborn (6/569,680) and 0.51/100,000 hospitalized infant (3/585,244), respectively. These results showed that the proportion of hospitalizations due to congenital TORCH infection is low, and the age at which patients were hospitalized was mainly in the neonatal period, except for congenital CMV infection.

Fig 1. Proportion of patients hospitalized for congenital TORCH infections.

Fig 1

Next, we analyzed the proportion of congenital TORCH infections hospitalizations to total hospitalization included in this study by region in different age groups. In the cases of neonates, patients from the Central China had the highest proportion of hospitalization (0.36‰, 24/67,524) while no neonates hospitalized with congenital TORCH infection in the Northeast China (Fig 1B). The hospitalization proportions of neonate patients from North China, East China, South China, Northwest China, and Southwest China were 0.13‰ (11/84,291), 0.21‰ (30/144,097), 0.28‰ (11/39,757), 0.09‰ (14/163,123), and 0.14‰ (8/58,083), respectively (Fig 1B). In the cases of infants, patients from the Northwest China had the highest proportion of hospitalization (0.41‰, 35/85275), and most of them were hospitalized with congenital CMV infection. The proportion of hospitalization of infant with congenital TORCH infection in the South China was the lowest (0.03‰, 1/37,510, Fig 1C). The hospitalization proportions of infant patients from Northeast China, North China, East China, Southwest China, and Central China were 0.07‰ (1/14,572), 0.09‰ (7/77,412), 0.08‰ (14/178,740), 0.05‰ (3/56,284), and 0.10‰ (14/135,451), respectively (Fig 1C).

Congenital toxoplasmosis

Five patients diagnosed with congenital toxoplasmosis included in FRCPD information acquisition and management were reported in this study. The male to female ratio was 1.5:1, 80% of patients were neonates (0–28 d group), two patients resided were from East China (Jiangxi), and the other three resided in Southwest China (Yunnan), South China (Guangdong), and Central China (Hunan), respectively. The median LOS was 19 days (IQR 4.5–23 days), which was the longest LOS among the hospitalized patients. The median expense of these children was 2,162.33 USD (IQR 637.51–3,523.25 USD). The main clinical manifestation of two patients was Toxoplasma meningoencephalitis, and one of them was accompanied by chorioretinitis (Table 2).

Table 2. The general sociodemographic characteristics and disease burden of pediatric patients with T. gondii infection during hospitalization from December 2015 to December 2020.

No. Sex Age (d) Province (Region) Ethnicity Residence Admission time Clinical manifestation LOS (d) Expense (USD)
1 Female 3 Yunnan (Southwest China) Non-Han Urban Apr, 2016 Pneumonia 5 834.31
2 Female 9 Jiangxi (East China) Han Rural Jan, 2018 Toxoplasma meningoencephalitis 22 3,446.41
3 Male 37 Guangdong (South China) Han Urban Jun, 2019 Unspecified symptoms 4 440.70
4 Male 5 Hunan (Central China) Han Rural Dec, 2020 Jaundice 19 2,162.33
5 Male 6 Jiangxi (East China) Han Urban Aug, 2020 Toxoplasma meningoencephalitis 24 3,600.19

T. gondii: Toxoplasma gondii

LOS: length of stay

IQR: inter quartile range

USD: US dollar

CRS

Twenty-seven patients diagnosed with CRS were reported, accounting for 15.61% of the hospitalizations with congenital TORCH infection. The ratio of males to females was 0.93:1, and the age distribution was mainly in the 0–28 d group (96.30%). The highest hospitalization proportion of neonate patients with CRS was observed in South China, accounting for 0.18‰ (7/39,757) of the total hospitalized neonate cases, followed by Central China (0.16‰, 11/67,524), East China (0.04‰, 7/144,097), and Northwest China (0.006‰, 1/163,123). No hospitalized patients with this diagnosis were reported in Northeast, North and Southwest China (Fig 1B). Only one infant was hospitalized with CRS in the Central China in the 29 d–1 y group (0.007‰, 1/135,451, Fig 1B). The number of hospitalizations in 2019 (especially from September to December) was the highest, the monthly hospitalization rate was 2.5 (admissions per 100,000) in both September (3/10,020) and November (3/10690, S1 Fig). The LOS was 9 d (IQR 5–15 d). Hospitalized children with CRS had the highest expense of 2,585.45 USD (IQR 1,524.88–4,010.98 USD) (Table 1).

The clinical symptom profiles of patients with CRS (including cardiovascular malformation, eye disorder, hearing damage, pneumonia, and neonatal thrombocytopenic purpura) were analyzed by the age category. Among the clinical manifestations of patients with CRS in the 0–28 d group, cardiovascular malformation accounted for the largest proportion (21 cases, 80.77%). One patient was included in the 29 d–<1 y group, and his main clinical manifestations were cardiovascular malformation, eye disorder, and hearing damage (Table 3). Fig 2 showed that CRS was often combined with a variety of clinical manifestations, among which cardiovascular malformation combined with eye disorder was more common (36.00%). According to the statistical analysis, the LOS and expenses were correspondingly increased for the children who were complicated with multiple organ injuries compared with patients with single organ injuries.

Table 3. The general sociodemographic characteristics of pediatric patients with CRS categorized by clinical manifestations during hospitalization from December 2015 to December 2020.

Number Clinical manifestation
Cardiovascular malformations Eye disorder Hearing damage Pneumonia Neonatal thrombocytopenic purpura Unspecified
Sex (n, %)
Male 13 12 (92.31) 2 (15.38) 2 (15.38) 2 (15.38) 1 (7.69) 1 (7.69)
Female 14 10 (71.43) 5 (35.71) 5 (35.71) 3 (21.43) 3 (21.43) 1 (7.14)
Age (n, %)
0–28 d 26 21 (80.77) 6 (23.08) 6 (23.08) 5 (19.23) 4 (15.38) 2 (7.69)
29 d–<1 y 1 1 (100.00) 1 (100.00) 1 (100.00) 0 (0.00) 0 (0.00) 0 (0.00)
Ethnicity (n, %)
Han 25 20 (80.00) 6 (24.00) 7 (28.00) 5 (20.00) 4 (16.00) 2 (8.00)
Non-Han 2 2 (100.00) 1 (50.00) 0 (0.00) 0 (0.00) 0 (0.00) 0 (0.00)
Residence (n, %)
Urban 10 8 (80.00) 1 (10.00) 2 (20.00) 2 (20.00) 1 (10.00) 1 (10.00)
Rural 17 14 (82.35) 6 (35.29) 5 (29.41) 3 (17.65) 3 (17.65) 1 (5.88)

CRS: congenital rubella syndrome

LOS: length of stay

IQR: inter quartile range

USD: US dollar

Fig 2. LOS and expenses of hospitalization due to CRS.

Fig 2

Congenital CMV infection

The proportion of children hospitalized with congenital CMV infection was the highest among patients with the four congenital infectious diseases. The male to female ratio was 1.28:1. Neonates accounted for 48.48%, while infant accounted for 51.52% (Table 1). In the cases of neonates, patients with congenital CMV infection have the highest proportion of hospitalized patients in Central China (0.18‰, 12/67,524, Fig 1B). However, in the infant group, the highest rate of hospitalization due to congenital CMV infection was in Northwest China (0.39‰, 33/85,275, Fig 1C). The seasonality could not be assessed because monthly case numbers for congenital CMV infection were rare (S2 Fig).

Our data suggested that the largest number of hospitalized children with CMV infection developed liver damage (36 cases, 27.27%), followed by lung damage (28 cases, 21.21%), blood disorders (11 cases, 8.33%), hearing damage (8 cases, 6.06%), nervous system damage (5 cases, 3.79%), myocardial damage (3 cases, 2.27%), eye damage (1 case, 0.76%), and multiple organ damage (9 cases, 6.82%). We observed that the LOS and expenses of patients with multiple organ damage were higher than those of patients with single organ injury. The highest expenses appeared in the pneumonia complicated with jaundice and liver damage group (7,205.937 USD) (Fig 3).

Fig 3. Proportion of patients with damage to different organs who were hospitalized with congenital CMV infection.

Fig 3

Congenital HSV infection

Nine patients with congenital HSV infection were reported in this study, accounting for 5.20% of the total hospitalized cases with congenital TORCH infection (Table 1). The ratio of males to females was 1.25:1. The age distribution was mainly in the 0–28 d group (66.67%), and the median age was 7 d (IQR 3–29 d). The neonatal cases mainly occurred in North China (0.04‰, 4/84,291, Fig 1B). The major clinical manifestations of these 9 patients are summarized in Table 4. Five patients were mainly characterized by unspecified symptoms, three patients presented with sepsis, and the remaining patient showed jaundice. The median of LOS and expenses were 6 days (IQR 2.5–18.5 d) and 935.03 USD (IQR 505.80–3,982.70 USD).

Table 4. The general sociodemographic characteristics and disease burden of pediatric patients with congenital HSV infection during hospitalization from December 2015 to December 2020.

No. Sex Age (d) Province (Region) Ethnicity Residence Admission time Clinical Complication LOS (d) Expense (USD)
1 Male 31 Shaanxi (Northwest China) Han Rural Jun, 2016 Unspecified 2 287.35
2 Male 3 Shaanxi (Northwest China) Han Rural Jul, 2016 Sepsis 7 935.03
3 Male 1 Inner Mongolia (North China) Non-Han Urban Jul, 2017 Unspecified 3 724.23
4 Female 31 Shaanxi (Northwest China) Han Urban Aug, 2017 Sepsis 21 4197.91
5 Female 29 Shandong (East China) Han Rural Jun, 2018 Unspecified 5 724.48
6 Male 16 Shanxi (North China) Han Urban Oct, 2018 Jaundice 29 7,127.02
7 Female 1 Shanxi (North China) Han Rural Jan, 2020 Unspecified 6 1,319.19
8 Male 7 Shanxi (North China) Han Rural Jan, 2020 Unspecified 1 246.72
9 Female 5 Hubei (Central China) Han Rural Oct, 2020 Sepsis 16 3,767.50
Median (IQR) - 7 (3–29) - - - - - 6 (2.5–18.5) 935.03 (505.80–3,982.70)

HSV: Herpes Simplex Virus

LOS: length of stay

IQR: inter quartile range

USD: US dollar

Mixed infection

The presented FSMRs data showed that two patients, diagnosed with CRS, had severe symptoms due to mixed infection with RV and HSV. One of them resided in Central China (3 d, female, Han ethnicity, Hunan, 2020), and another resided in South China (1 d, male, Han ethnicity, Guangdong, 2019). The main complication of the female patient was cardiovascular malformation, and that of the male patient was sepsis. Their LOSs (25 d and 30 d, respectively) and expenses (4,561.07 USD and 7,282.05 USD, respectively) were higher than those of patients with CRS alone (Table 5).

Table 5. The general sociodemographic characteristics and disease burden of pediatric patients with a mixed infection during hospitalization from December 2015 to December 2020.

No. Sex Age (days) Infection Province (Region) Ethnicity Residence Admission time Clinical Complication LOS (d) Expense (USD)
1 Female 3 RV and HSV Hunan (Central China) Han Rural May, 2020 Cardiovascular malformation 25 4,561.07
2 Male 1 RV and HSV Guangdong (South China) Han Rural Oct, 2019 Sepsis 30 7,282.05

LOS: length of stay

IQR: inter quartile range

USD: US dollar

Discussion

Studies have reported that TORCH infections are currently important risk factors for adverse pregnancy outcomes in China, particularly congenital malformations [22]. This study intuitively describes the epidemiological characteristics and the disease burden of hospitalized children with congenital TORCH infections.

A study of TORCH serological screening in Chinese neonates showed that the seroprevalence of TORCH-IgM was approximately 0.67%. Among these patients, the seroprevalence of CMV was the highest [11, 23]. Our data showed that the hospitalization rate due to congenital TORCH infections was extremely low (17.56 per 100,000 hospitalized neonates). Wang et al. reported that the seroprevalence of T. gondii among women of childbearing age was 0.35% for IgM and 4.35% for IgG in Xi’an, China [24], which was lower than that in other countries (50–80% in Brazil, 44% in France, and 9.1% in the USA) [25]. Our data showed that only five cases of congenital toxoplasmosis were recorded from 2015 to 2020, indicating that the infection rate of congenital toxoplasmosis in China is indeed at a low level, which may benefit from the increased awareness of protection against toxoplasma infection among women of childbearing age (for example avoiding contact with pets and eating raw meat). In contrast to the low hospitalization rate, the disease burden of congenital toxoplasmosis was considerable. The LOS for congenital toxoplasmosis was the highest, and the hospitalization expense was also in the second position among congenital TORCH infectious diseases, indicating that congenital toxoplasmosis, although uncommon, may cause severe clinical symptoms and a heavy disease burden. Torgerson et al. reported that the global burden of congenital toxoplasmosis was estimated to be 9.6 disability-adjusted life years (DALYs) per 1,000 live births [3]. Therefore, more attention should be given to strengthening prepregnancy toxoplasmosis detection and educating people on toxoplasmosis prevention knowledge to reduce the incidence of congenital toxoplasmosis.

RV remains an important pathogen worldwide, with an estimated 100,000 cases of CRS per year [26]. Our results showed that the proportion of CRS cases was 0.7 per 100,000 hospitalized neonates, which was higher than that in England (0.18 per 100,000) [27]. The implementation of immunization programs with two doses of the measles–mumps–rubella (MMR) vaccine in China occurred later than that in the UK and might be responsible for the result. Nevertheless, the number of CRS cases has decreased significantly since the universal vaccination began in China in 2008 [7]. A large RV outbreak that occurred in China during 2019, which primarily involved primarily adolescents and reproductive-aged adults [7]. A total of 32,539 cases (2.33 per 100,000) were reported, and most of them occurred from March to June. Among them, 98.41% of patients with rubella over 20 years old had no or unknown immunization history with rubella and the rubella-containing vaccines (RCV), and the vast majority of women who are currently of childbearing age have not been vaccinated against RCV [28]. Our statistics showed that 59.26% of neonatal patients with CRS were hospitalized in 2019. Markedly, most cases occurred from September to December, indicating that their mother might have been infected with RV in early pregnancy, resulting in CRS. A nationwide rubella antibody serological survey of approximately 800,000 women of childbearing age showed that the positive rate of rubella antibodies among Chinese women of childbearing age between 20 and 29 y was only 59%, which did not reach 85% of the population to form an effective immune barrier [29]. Achieving complete anti-rubella vaccination coverage for uncovered adolescent girls and women of childbearing age along with a universal immunization program consisting of a MMR vaccine is paramount. The disease burden of CRS may be very substantial due to the severe clinical symptoms caused by CRS (cardiovascular malformation, cataracts, and deafness) [30]. In the present study, 80% of hospitalized children with CRS had cardiovascular malformations, indicating that RV is a risk factor for neonatal teratogenicity, and that high surgical treatment costs will be incurred. The economic burden of CRS was heavy, and infants are recommended be vaccinated against RV in a timely manner [31]. Strengthening CRS surveillance is conducive to the rapid identification and control of rubella outbreaks, preventing the secondary transmission of rubella due to CRS cases, and has important value for prevention and control significance.

Congenital CMV infection is the most common congenital infection worldwide. The prevalence of congenital CMV infections is approximately 0.2% to 2% (average 0.65%) in developed countries and 6–14% in developing countries [32]. According to a previous study, the CMV seroprevalence was 98.11% and the congenital CMV prevalence was 1.32% in China [33]. Our statistical analyses showed that children with congenital CMV infection had the highest hospitalization rate among those with TORCH infection. Furthermore, the proportion of hospitalizations for congenital CMV infections in the 29 d–<1 y group was similar to that in the 0–28 d group, possibly because most neonates with congenital CMV infection detected at birth were asymptomatic and were not admitted until obvious clinical manifestations occurred, such as liver damage. In addition, the proportion of children with congenital malformations was 4.76%, suggesting that the teratogenic effect of congenital CMV infection must not be ignored, and the prevention of congenital CMV infection during pregnancy is still an important issue that should be considered. Routine screening for neonatal congenital CMV infection and proactive preventive and therapeutic measures might help reduce the disease burden caused by congenital CMV infection. Congenital CMV infection can induce hearing loss; however, only 5.54% of children present hearing damage. We speculated that the reason may be the lack of outpatient information and follow-up information. Only FSMRs of hospitalized children were collected in this study, and the effect of the congenital CMV infection probability might be underestimated.

Studies have reported that the incidence of neonatal HSV infection is relatively low, occurring in 1 in 3,000 to 20,000 livebirths [34][13]. The incidence in China is unknown due to a lack of reported data on neonatal HSV infection. A study indicated that between 2008 and 2010 in Hong Kong, China, only one case of the neonate was infected with HSV [22]. In our study, the proportion of hospitalizations for congenital HSV infections was 1.05/100,000 neonatal patients, indicating that the incidence of congenital HSV infection is comparatively low in China. Neonatal disseminated HSV infection may cause viral sepsis, liver failure, etc., with the worst prognosis [35]. According to our findings, the disease burden (including LOS and expenses) increases significantly when patients develop complications. Early diagnosis and timely treatment of neonatal HSV infection are very important to improve national population quality. We also identified mixed infections with HSV and RV; the explanation might be that there may be a certain mutual activation may exist between various pathogens causing TORCH infections [36], and its mechanism requires further exploration.

Some limitations existed in this study. First, we only collected FSMRs for hospitalized children with congenital TORCH infection and lacked a considerable amount of medical information on children attending outpatient clinics, as well as follow-up information for these children. Second, this study only statistically analyzed the hospitalization due to four major pathogens causing TORCH and did not include other pathogens, such as parvovirus B19, herpes zoster virus, and syphilis (it was monitored by an independent national surveillance network). Therefore, the effect of congenital TORCH infection may be underestimated. Third, the FUTURE database does not contain a detailed course of disease, laboratory examination results, and treatment records of patients, which may lead to the simplified and insufficiently comprehensive of the data. Fourth, the database was unable to collect information on all patients with mild symptoms of TORCH infection and the loss of infants who died secondary to their infection or fetal stillbirth, and the epidemiological burden of congenital TORCH infections is underestimated. Finally, because of the number of hospitalized patients with some diseases was relatively rare, the calculated disease burden may differ from the actual situation, and requires an expanded version of the FUTURE database to reinforce the conclusions obtained in this study.

Conclusion

We combed the FUTURE database of 27 children’s hospitals in China and described the general epidemiological characteristics and the disease burden of hospitalized children infected with congenital TORCH (T. gondii, RV, CMV, and HSV) infection. The hospitalization rate due to congenital TORCH infections was extremely low (17.56 per 100,000 hospitalized neonates). However, they still imposed a significant medical burden on clinical and public health in China. These data illustrate the importance of improving screening for congenital TORCH infections in the early diagnosis and treatment of neonatal patients. Increased awareness of the epidemiological characteristics and the disease burden of congenital TORCH infections is conducive to public health education (promoting antenatal hygiene behaviors and immunization), formulating targeted strategies (utility of neonatal screening), and research (through vaccine development).

Supporting information

S1 Fig. Hospitalization rate and number of neonates with CRS (n = 26), December 2015–December 2020.

M (n): number of monthly hospitalizations, Y (n): number of yearly hospitalizations.

(TIF)

S2 Fig. Hospitalization rate and number of congenital CMV infections (n = 132), December 2015–December 2020.

M (n): number of monthly hospitalizations, Y (n): number of yearly hospitalizations.

(TIF)

Acknowledgments

We are grateful to investigators from members of the Futang Research Center of Pediatric Development (FRCPD).

Data Availability

All relevant data are within the manuscript and its Supporting information files.

Funding Statement

National Natural Science Foundation of China (No.82002130) and Beijing Natural Science Foundation (No.7222059) were awarded to R.W. The CAMS Innovation Fund for Medical Sciences (No.2019-I2M-5-026) was awarded to ZD. X. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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PLoS Negl Trop Dis. doi: 10.1371/journal.pntd.0010861.r001

Decision Letter 0

Marcelo U Ferreira, Winsley Rose

15 Aug 2022

Dear Dr. Wang,

Thank you very much for submitting your manuscript "The epidemiology and disease burden of congenital TORCH infections among hospitalized children in China: A national cross-sectional study" for consideration at PLOS Neglected Tropical Diseases. As with all papers reviewed by the journal, your manuscript was reviewed by members of the editorial board and by several independent reviewers. In light of the reviews (below this email), we would like to invite the resubmission of a significantly-revised version that takes into account the reviewers' comments.

The authors have described the disease burden of congenital TORCH infections and described their clinical features from a nationwide database. There are considerable methodological constraints which require clarity. The authors need to clarify how the diagnosis of a congenital TORCH infection was made. As has been pointed out by the reviewers as well, the basis of diagnosis of TORCH infection especially that of congenital CMV infection need to be described. Congenital CMV is the commonest congenital infection described in the study and over 50% of the children with congenital CMV infection are beyond the neonatal period. A serological or PCR based diagnosis made beyond 3 weeks cannot differentiate congenital from acquired CMV infection. There are other issues that have been raised by the reviewers and the manuscript requires considerable revision before it can be accepted.

We cannot make any decision about publication until we have seen the revised manuscript and your response to the reviewers' comments. Your revised manuscript is also likely to be sent to reviewers for further evaluation.

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[1] A letter containing a detailed list of your responses to the review comments and a description of the changes you have made in the manuscript. Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

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Sincerely,

Winsley Rose

Academic Editor

PLOS Neglected Tropical Diseases

Marcelo Ferreira

Section Editor

PLOS Neglected Tropical Diseases

***********************

The authors have described the disease burden of congenital TORCH infections and described their clinical features from a nationwide database. There are considerable methodological constraints which require clarity. The authors need to clarify how the diagnosis of a congenital TORCH infection was made. As has been pointed out by the reviewers as well, the basis of diagnosis of TORCH infection especially that of congenital CMV infection need to be described. Congenital CMV is the commonest congenital infection described in the study and over 50% of the children with congenital CMV infection are beyond the neonatal period. A serological or PCR based diagnosis made beyond 3 weeks cannot differentiate congenital from acquired CMV infection. There are other issues that have been raised by the reviewers and the manuscript requires considerable revision before it can be accepted.

Reviewer's Responses to Questions

Key Review Criteria Required for Acceptance?

As you describe the new analyses required for acceptance, please consider the following:

Methods

-Are the objectives of the study clearly articulated with a clear testable hypothesis stated?

-Is the study design appropriate to address the stated objectives?

-Is the population clearly described and appropriate for the hypothesis being tested?

-Is the sample size sufficient to ensure adequate power to address the hypothesis being tested?

-Were correct statistical analysis used to support conclusions?

-Are there concerns about ethical or regulatory requirements being met?

Reviewer #1: The authors describe the epidemiology and the disease burden of congenital TORCH infections (Toxoplasmosis, CMV, Rubella, HSV) among hospitalized infants in China. The data has been derived from the FUTURE database which collects data from 27 centres from various regions of China. The authors have stated that the data was on all infants admitted to these hospitals between 2015 and 2020.

Since they have limited their objectives to number of admissions with the TORCH infections, length of stay and treatment cost, this seems reasonable.

However, to make the subsequent data more meaningful, some more background data needs to be given:

1. How were the diagnosis of each of these infections established? Only serological tests or were molecular and/or cultures used?

2. Were all the diagnoses made in the newborn period? Especially for CMV, if diagnosis was made after 3 weeks , it is likely to be a postnatal infection. This distinction, to a lesser extent, has to be made for rubella and HSV also. So, the authors have to be categorical that the diagnosis of a CONGENITAL infection was established even though the child may have been admitted at a later age.

3. It is very unclear from the write up if children below 1 year were included or all children ≤ 18 years were included in the analysis. The inclusion criteria says ≤18 years, but the tables all use 29 days- 1 year. The year by year analysis and the month-wise admissions would have little meaning if ALL children ≤18 years were included.

4. The exclusion criteria excludes children where data regarding age, gender, burden of disease, diagnosis were not complete. While it makes perfect sense to exclude those with incomplete diagnosis, it would be interesting to see the numbers of those excluded on the basis of lack of other criteria especially if the numbers are large.

5. Since the authors have chosen to determine the ethnicity of the patients with infections, it is worthwhile giving the ethnic diversity (Han vs Non-Han) of China as a whole or within the population analyzed. If this is almost the same as the proportion among the infected children, then there is no ethnic variation.

Reviewer #2: This study is a descriptive study, but the field is poorly studied from an epidemiologic standpoint. The true burden of TORCH infections is under characterized and this study adds value into this field. The statistical methods are relatively simple as a descriptive study and appropriate. The data seem to be abstracted from a discharge face sheet which is not clear to me what this contains- I suspect it is akin to a US medical system discharge summary, but the data abstraction should be better described.

--------------------

Results

-Does the analysis presented match the analysis plan?

-Are the results clearly and completely presented?

-Are the figures (Tables, Images) of sufficient quality for clarity?

Reviewer #1: To make better sense of the vast data collected, I would like more data given.

1. How many hospitalized children were there in each age group over the 5 years? If we have the number of births/ newborn in the 27 hospitals and the number of neonatal diagnosis of the TORCH infections, this would give a better indicator of the burden of the infections.

2. There is a wide disparity in the distribution of hospitals between the regions- 8 in East China and 2 each in South and South-West China. Hence it does not make sense to give the percentage of each infection as a proportion of the total infections in each region. If the population studied in each region is taken as the denominator, then we would be able to glean if an infection is in fact more prevalent in a particular region. Hence, the way this is given in the text and the tables now should be removed or modified.

3. As previously mentioned, the season of admission may be valid if only neonatal infections are included. Otherwise, giving this data for all children between 0-12 months gives no meaningful information. A baby born in one particular month could be admitted with cardiac or liver cell failure any time over the next year! If this data is to be included, it should changed to include only newborn. That would give some idea of the seasonality of the infection in the mother.

Tables and figures:

1. The tables are exhaustive and can be made more brief to give only the relevant information. For example, the clinical manifestations in various organs in CRS (Table 3 ) in each region is redundant. As previously mentioned, ethnicity would have relevance if the background ethnic make-up is known.

2. The supplementary figures S1 and S2 are too unclear. No details could be made out.

Reviewer #2: The analysis and the analysis plan matches.

There are some significant limitations in the data- Parvovirus should be excluded as parvovirus has implications in vertical transmission antenatally and can cause hydrops, stillbirth and severe anemia. Post natal admission for parvovirus would be atypical and the authors should exclude it.

It is difficult to believe that there was no vertical transmission of HSV. This is a relatively common TORCH pathogen and certainly exists at higher rates than congential toxo.

--------------------

Conclusions

-Are the conclusions supported by the data presented?

-Are the limitations of analysis clearly described?

-Do the authors discuss how these data can be helpful to advance our understanding of the topic under study?

-Is public health relevance addressed?

Reviewer #1: If necessary changes as suggested could be made, the conclusions would be more clear. The authors have clearly identified the limitations of the analysis and have described them. I would like some more detailing on how they expect this data to have public relevance in China.

Reviewer #2: In the conclusions, the authors perform a comparative analysis of different TORCH infections. This is likely inappropriate due to the wide variety in clinical sequelae, clinical presentation and antenatal route of infection.

In the section on CRS, additional information on maternal immunization history and rubella susceptibility in the setting of the described outbreak is warranted. Vaccination is a well described strategy to eliminate CRS and should be commented on.

The authors should describe the epidemiology of postnatal serology and the difference in serologic titers (particularly positive IgG) and congenital TORCH infection diagnosis. Both background on transplacental passage and stability of IgG should be described as well as a description on the utility of serology for postnatal screening as this is elucidated in several areas.

Several limitations of this study should be discussed in the conclusions including the inability to detect mildly symptomatic infections for all TORCH pathogens as well as the loss of infants who died secondary to their infection or fetal stillbirth. While this dataset is extremely important and adds to the data, it underrepresents the epidemiologic burden of TORCH and this should be explicitly stated

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Editorial and Data Presentation Modifications?

Use this section for editorial suggestions as well as relatively minor modifications of existing data that would enhance clarity. If the only modifications needed are minor and/or editorial, you may wish to recommend “Minor Revision” or “Accept”.

Reviewer #1: More data needs to be presented before the conclusions can be arrived in this study. The language used needs a fair bit of editing before publication.

Reviewer #2: The introduction is very short and largely written in a matter of fact matter without a lead into the subject material and study desigen. I would recommend additional background and information should be included to introduce and link the study.

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Summary and General Comments

Use this section to provide overall comments, discuss strengths/weaknesses of the study, novelty, significance, general execution and scholarship. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. If requesting major revision, please articulate the new experiments that are needed.

Reviewer #1: The authors have presented data on congenital TORCH infections among hospitalized children in China over a nearly 6 year period from China. It should give a good idea about the burden of the problem (health and economic) and the prevalence of these infections in China to direct public health measures. I think this would be good data.

However, more background data needs to be given and the analysis needs to be modified to make the results and conclusions more valid.

Reviewer #2: The manuscript by Dr. Zhang and colleagues about the epidemiology and burden of TORCH infections is a novel study that substantially adds to information in the field on this topic. The study design is a retrospective collection of data from children age 0-1 with a diagnosis code of a congenital infection. They identified 173 patients from a wide and diverse geographic region in China from their database. They then go to describe the distribution attributable to different pathogens and some information on the sequelae of infection.

This manuscript would benefit from additional detail regarding serologic screening, background on the diagnosis of vertical transmission versus postnatal transmission (well described in CMV for example) as well as an additional figure with the geographic region of each infection (as this is an epidemiologic study and local geopolitical and cultural risks may contribute to disease prevalence).

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Reviewer #1: No

Reviewer #2: Yes: Christina Megli MD/PhD

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PLoS Negl Trop Dis. doi: 10.1371/journal.pntd.0010861.r003

Decision Letter 1

Marcelo U Ferreira, Winsley Rose

3 Oct 2022

Dear Dr. Wang,

We are pleased to inform you that your manuscript 'The epidemiology and disease burden of congenital TORCH infections among hospitalized children in China: A national cross-sectional study' has been provisionally accepted for publication in PLOS Neglected Tropical Diseases.

Before your manuscript can be formally accepted you will need to complete some formatting changes, which you will receive in a follow up email. A member of our team will be in touch with a set of requests.

Please note that your manuscript will not be scheduled for publication until you have made the required changes, so a swift response is appreciated.

IMPORTANT: The editorial review process is now complete. PLOS will only permit corrections to spelling, formatting or significant scientific errors from this point onwards. Requests for major changes, or any which affect the scientific understanding of your work, will cause delays to the publication date of your manuscript.

Should you, your institution's press office or the journal office choose to press release your paper, you will automatically be opted out of early publication. We ask that you notify us now if you or your institution is planning to press release the article. All press must be co-ordinated with PLOS.

Thank you again for supporting Open Access publishing; we are looking forward to publishing your work in PLOS Neglected Tropical Diseases.

Best regards,

Winsley Rose

Academic Editor

PLOS Neglected Tropical Diseases

Marcelo Ferreira

Section Editor

PLOS Neglected Tropical Diseases

***********************************************************

The revised version is accepted for publication.

Reviewer's Responses to Questions

Key Review Criteria Required for Acceptance?

As you describe the new analyses required for acceptance, please consider the following:

Methods

-Are the objectives of the study clearly articulated with a clear testable hypothesis stated?

-Is the study design appropriate to address the stated objectives?

-Is the population clearly described and appropriate for the hypothesis being tested?

-Is the sample size sufficient to ensure adequate power to address the hypothesis being tested?

-Were correct statistical analysis used to support conclusions?

-Are there concerns about ethical or regulatory requirements being met?

Reviewer #1: The objectives, study design and statistical analysis are appropriate.

There are no ethical concerns.

Reviewer #2: Yes- the study is a novel observational study. They clearly describe the methodology.

**********

Results

-Does the analysis presented match the analysis plan?

-Are the results clearly and completely presented?

-Are the figures (Tables, Images) of sufficient quality for clarity?

Reviewer #1: Overall, the results in the edited version are well presented. I would suggest some changes in the manuscript:

1. In the results section (Lines 217-225), the authors could change the terminology to "the proportion of hospitalizations for congenital TORCH infections per 100,000 patients was 17.56 (100/569,680) in the 0–28 d group (neonate)" to "the proportion of hospitalizations for congenital TORCH infections was 17.56/ 100, 000 newborn (or alternatively as "per 100,000 live births" if most newborn were inborn in the hospitals) (100/569,680)." For all the individual TORCH infections too, it makes more sense to give the numbers as "per 100,000 newborn or live births". For the over 1 month group, they can quote as per 100,000 admissions. Please add the denominators to each individual result.

2. A query about figure 1: There is a gross discrepancy between the admissions in the neonatal period and later admissions in South and Northwest regions. It is difficult to imagine that none of the newborn with CRS or CMV in South China needed readmission. The exact opposite in the Northwest. Though the number of newborn diagnosed with TORCH is less, it has the highest number of childhood admissions in the country. Is there a difference in testing procedures/ admission criteria in the Northwest? Can the authors recheck these results? And, if possible, give some sort of explanation for these?

3. In an article which gives nationwide data on TORCH infections, it makes little sense to give the individual patient characteristics of Toxoplasmosis, HSV and mixed (Tables 2, 4 and 5). They do not add much information. The data is summarized in the text. These seem to be redundant and may be removed or put as supplementary material.

Reviewer #2: The figures are comprehensive and excellent summary of the data. The results are clearly described and presented. This is a substantial improvement from previous version.

**********

Conclusions

-Are the conclusions supported by the data presented?

-Are the limitations of analysis clearly described?

-Do the authors discuss how these data can be helpful to advance our understanding of the topic under study?

-Is public health relevance addressed?

Reviewer #1: No issues

Reviewer #2: The data are supported by the conclusions and the limitations and analysis are clearly presented. The revisions have provided substantial clarity and language improvements.

**********

Editorial and Data Presentation Modifications?

Use this section for editorial suggestions as well as relatively minor modifications of existing data that would enhance clarity. If the only modifications needed are minor and/or editorial, you may wish to recommend “Minor Revision” or “Accept”.

Reviewer #1: I think the article needs minor revisions as described above.

Reviewer #2: (No Response)

**********

Summary and General Comments

Use this section to provide overall comments, discuss strengths/weaknesses of the study, novelty, significance, general execution and scholarship. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. If requesting major revision, please articulate the new experiments that are needed.

Reviewer #1: The authors have presented data on congenital TORCH infections among hospitalized children in China over a nearly 6 year period. It should give a good idea about the burden of the problem (health and economic) and the prevalence of these

infections in China to direct public health measures. In the present format, the authors have detailed the issues with each of the TORCH infections well.

Reviewer #2: The authors have thoughtfully and extensively addressed the concerns of the reviewers and have produced a comprehensive manuscript that is interesting and somewhat novel to describe the burden of TORCH infections in China. They have clearly described epidemiologic, cost and burden of disease within the limitations of their database. The result is a significant and novel publication that will be of interest.

**********

PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Sridhar Santhanam

Reviewer #2: Yes: Christina Megli

PLoS Negl Trop Dis. doi: 10.1371/journal.pntd.0010861.r004

Acceptance letter

Marcelo U Ferreira, Winsley Rose

8 Oct 2022

Dear Dr. Wang,

We are delighted to inform you that your manuscript, "The epidemiology and disease burden of congenital TORCH infections among hospitalized children in China: A national cross-sectional study," has been formally accepted for publication in PLOS Neglected Tropical Diseases.

We have now passed your article onto the PLOS Production Department who will complete the rest of the publication process. All authors will receive a confirmation email upon publication.

The corresponding author will soon be receiving a typeset proof for review, to ensure errors have not been introduced during production. Please review the PDF proof of your manuscript carefully, as this is the last chance to correct any scientific or type-setting errors. Please note that major changes, or those which affect the scientific understanding of the work, will likely cause delays to the publication date of your manuscript. Note: Proofs for Front Matter articles (Editorial, Viewpoint, Symposium, Review, etc...) are generated on a different schedule and may not be made available as quickly.

Soon after your final files are uploaded, the early version of your manuscript will be published online unless you opted out of this process. The date of the early version will be your article's publication date. The final article will be published to the same URL, and all versions of the paper will be accessible to readers.

Thank you again for supporting open-access publishing; we are looking forward to publishing your work in PLOS Neglected Tropical Diseases.

Best regards,

Shaden Kamhawi

co-Editor-in-Chief

PLOS Neglected Tropical Diseases

Paul Brindley

co-Editor-in-Chief

PLOS Neglected Tropical Diseases

Associated Data

    This section collects any data citations, data availability statements, or supplementary materials included in this article.

    Supplementary Materials

    S1 Fig. Hospitalization rate and number of neonates with CRS (n = 26), December 2015–December 2020.

    M (n): number of monthly hospitalizations, Y (n): number of yearly hospitalizations.

    (TIF)

    S2 Fig. Hospitalization rate and number of congenital CMV infections (n = 132), December 2015–December 2020.

    M (n): number of monthly hospitalizations, Y (n): number of yearly hospitalizations.

    (TIF)

    Attachment

    Submitted filename: Authors Response to Reviewers Comments.docx

    Data Availability Statement

    All relevant data are within the manuscript and its Supporting information files.


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