Skip to main content
NCBI home page
Clinical and Experimental Pediatrics logoLink to Clinical and Experimental Pediatrics
. 2021 Feb 5;64(11):575–581. doi: 10.3345/cep.2020.01039

The global prevalence of Toxocara spp. in pediatrics: a systematic review and meta-analysis

Behnam Abedi 1, Mehran Akbari 2, Sahar KhodaShenas 3, Alireza Tabibzadeh 4, Ali Abedi 5, Reza Ghasemikhah 6, Marzieh Soheili 7,8, Shnoo Bayazidi 9, Yousef Moradi 10,✉
PMCID: PMC8566795  PMID: 33561339

Abstract

Background

Toxocariasis is a zoonotic parasitic disease caused by Toxocara canis and Toxocara cati in humans. Various types of T. canis are important.

Purpose

The current study aimed to investigate the prevalence of Toxocara spp. in pediatrics in the context of a systematic review and meta-analysis.

Methods

The MEDLINE (PubMed), Web of Sciences, Embase, Google Scholar, Scopus, and Cumulative Index of Nursing and Allied Health databases were searched to identify peer-reviewed studies published between January 2000 and December 2019 that report the prevalence of Toxocara spp. in pediatrics. The evaluation of articles based on the inclusion and exclusion criteria was performed by 2 researchers individually.

Results

The results of 31 relevant studies indicated that the prevalence of Toxocara spp. was 3%–79% in 10,676 cases. The pooled estimate of global prevalence of Toxocara spp. in pediatrics was 30 (95% confidence interval, 22%–37%; I2=99.11%; P=0.00). The prevalence was higher in Asian populations than in European, American, and African populations.

Conclusion

Health policymakers should be more attentive to future research and approaches to Toxocara spp. and other zoonotic diseases to improve culture and identify socioeconomically important factors.

Keywords: Learning disability, Neurobiology, Reading disability (dyslexia)

Introduction

Toxocariasis or visceral migraine laryngeal syndrome is a zoonotic parasitic disease caused by Toxocara canis and Toxocara cati in humans. Various types of T. canis in particular can be important [1,2]. Each adult worm in the intestines of infected dogs and cats can release a large number of eggs daily through defecation. Toxocariasis is mostly transmitted to humans via water, food, and soil contaminated with eggs [2,3]. The eggs of this parasite are opened after entering the human digestive system. The larvae then pass through the intestinal mucosa to the bloodstream and diffuse into organs such as the liver, brain, and eye. Although the larva will be recognized and limited by the immune system forming granuloma, they can survive and persist in this form for up to 11 years [4].

The visceral larva migrans (VLM), ocular larvae (OLM), and overt toxocariasis are the most common types of larvae. The clinical symptoms of infection are nonspecific but can include neurological, ocular, pulmonary (asthmatic), dermatological, and rheumatoid arthritis [5]. The pathology of this parasite is variable, but it can induce peripheral eosinophilia (20%–40%) and fever of unknown origin. The prevalence of parasites varies among geographic regions at rates of 2%–90% [6-8].

Pediatrics are more susceptible to Toxocara infection since they are more likely to place a contaminated hand or even an egg into their mouth [9]. Seroepidemiological evaluations in different countries indicated a global distribution of toxocariasis. Considering the importance of the prevalence of this parasite in the population, this study aimed to evaluate the prevalence of toxocariasis in pediatric patients younger than 20 years of age based on a systematic review and meta-analysis of published studies.

Methods

This study was performed according to the MOOSE (MetaAnalyses of Observational Studies in Epidemiology) and the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) [10-12].

1. Search strategy

In this systematic review, we assessed all original research studies that were relevant to the topic by searching the MEDLINE (PubMed), Web of Sciences, Embase, Google Scholar, Scopus, and Cumulative Index of Nursing and Allied Health databases using keywords such as toxocariasis, Toxocara, Toxocara-antibodies, Pediatrics, Toxocara canis, and Toxocara cati. The search was limited to articles published between January 2000 and December 2019. The researchers searched these databases and manually searched the reference lists and gray literature. Duplicate entries were reviewed by considering the title of published papers, authors, year of publication, and specifications of the source types. In questionable records, the texts were compared. After abstract and title review, some of the articles were eliminated. The retrieved papers were evaluated by 2 researchers (YM, BA) based on the inclusion and exclusion criteria.

2. Eligibility criteria

For the current study, the inclusion criteria were publication in the English language and publication between January 2000 and December 2019. The study design and methodologies were cross-sectional. All other studies, such as reviews or meta-analyses, were excluded from the screening. Articles that were conducted on animals were also excluded.

We included all English observational studies published between January 2000 to December 2019 that assessed the prevalence of toxocariasis, therapeutic management, signs, and symptoms in pediatric patients with toxocariasis. Cross-sectional studies were also included. We excluded duplicate non–peer-reviewed, review, or meta-analysis articles and papers for which the abstracts and full texts were not available.

3. Data extraction

All of the included studies were listed by EndNote software (EndNote X7, Thomson Reuters, Toronto, ON, Canada) and subjected to review and data extraction by 3 independent authors. Two reviewers independently (BA and RGH) extracted the required data from the data contained in the identified articles using a uniform Excel sheet. Discrepancies in the extracted data were resolved through consensus. If agreement could not be reached, it was resolved by referral to a third investigator (YM). For the current study, the data extraction section contained the first author’s name, year of publication, study location, study type, sample size, age, positive population prevalence, and method of detecting the infection.

4. Risk of bias

The quality of all studies was assessed by 2 independent authors using the Modified Newcastle-Ottawa Scale for cross-sectional studies [13].

5. Statistical analysis

We used a random-effects model to generate a pooled prevalence presented as percentage and 95% confidence interval (CI) with Metaprop order. Interstudy heterogeneity was assessed using the I2 heterogeneity statistic reported as a percentage (%) to determine the extent of interstudy variation. A forest plot was used to present the meta-analysis results schematically. Egger test and a funnel plot were applied to evaluate the presence of publication bias. In addition, a subgroup analysis was performed to identify different sources of heterogeneity. The statistical analysis was performed using STATA 15.0 (Stata Corp., College Station, TX, USA), and statistical significance was set at P<0.05.

Results

The conducted search retrieved 2,395 studies. After duplicate removal and title and abstract screening, 276 relevant studies remained. The search and screening results are illustrated in Fig. 1. The assessment of 31 studies revealed that the prevalence of Toxocara was 3%–79% in 10,676 cases. Of the total number of children (10,676), 3,525 had Toxocara infection (Table 1). In addition, most of the conducted studies used enzymelinked immunosorbent assay (ELISA) to diagnose the infection. Furthermore, in most of the mentioned studies, the patients were younger than 12 years of age. The results from the different included studies are listed in Table 1.

Fig. 1.

Fig. 1.

Open in a new tab

Preferred Reporting Items for Systematic Reviews and Meta-Analyses diagram and search strategy results.

Table 1.

Studies examining the prevalence of Toxocara spp. in pediatric patients

Study Country Year Sample size (n) Age range (yr) Specimen Study design Prevalence (%) Methods NOS score
Sadjjadi et al. [21] Iran 2000 519 6–13 Serum CS 51.30 ELISA 6
Alonso et al. [33] Brazil 2000 206 1–14 Serum CS 37.9 SLISA 7
Aguiar-Santos et al. [34] Brazil 2004 386 0–18 Serum CS 39.4 ELISA 7
Muradian et al. [35] Brazil 2005 338 1–15 Serum CS 79.40 ELISA 7
Paludo et al. [36] Brazil 2007 450 1–12 Serum CS 28.8 ELISA 7
Nourian et al. [37] Iran 2008 810 1–2 Serum CS 2.7 ELISA 6
Espinoza et al. [38] Peru 2008 182 6–12 Serum CS 32.5 ELISA 6
Zarnowska et al. [39] Poland 2008 343 - Serum CS 24.70 ELISA 6
Dar et al. [40] India 2008 110 5–16 Serum CS 32.7 ELISA 6
Antonios et al. [41] Egypt 2008 128 1–12 Serum CS 6 ELISA 6
Alavi et al. [42] Iran 2008 29 6–15 Serum CS 55 ELISA 7
Sviben et al. [43] Croatia 2009 142 3–18 Serum CS 43 ELISA 7
Yazar et al. [44] Turkey 2010 112 - Stool CS 21.4 ELISA 6
Santar m et al. [45] Brazil 2011 252 1–15 Serum CS 11.10 ELISA 6
Mattia et al. [46] Brazil 2012 353 0–12 Serum CS 36.8 ELISA 8
Manini et al. [9] Brazil 2012 90 1–12 Serum CS 17.80 ELISA 7
Sariego et al. [47] Cuban 2012 1,011 5–14 Serum CS 38.80 ELISA 6
Schoenardie et al. [48] Brazil 2013 427 1–12 Serum CS 50.60 ELISA 6
Kanobana et al. [49] Cuban 2013 958 5–14 Serum CS 40 ELISA 6
Guilherme et al. [50] Brazil 2013 167 0–15 Serum CS 4.2 ELISA 7
Pautova et al. [51] Russia 2013 144 1–17 Serum CS 18.8 ELISA 8
Mendon a et al. [52] Brazil 2013 1,309 4–11 Serum CS 48.4 ELISA 7
Oliart-Guzm n et al. [53] Brazil 2014 539 6 m–69 m Serum CS 23-28 ELISA 7
Archelli et al. [54] Spain 2014 120 0–3 Serum CS 38.3 ELISA 7
Marchioro et al. [55] Brazil 2015 554 1–12 Serum CS 7.4 ELISA 7
Mart nez et al. [56] Venezuela 2015 224 1–6 Serum CS 29 ELISA 7
Cort s et al. [57] Mexico 2015 183 3–16 Serum CS 12 ELISA 7
Mazur-Melewska et al. [23] Poland 2016 42 1–18 Serum CS 30.3 ELISA 6
Gabrielli et al. [57] Serbia 2017 40 2–14 Serum CS 10 ELISA/WB 7
Sowemimo et al. [58] Nigeria 2017 308 0–5 Serum CS 37 WB 7
Fialho et al. [59] Brazil 2017 200 1–12 Serum CS 16 ELISA 7
Open in a new tab

NOS, Newcastle-Ottawa scale; CS, cross-sectional; ELISA, enzyme-linked immunosorbent assay; CE, cryptogenic epilepsy; WB, Western blot.

The results demonstrated that the pooled prevalence of Toxocara in pediatric patients worldwide was 30 (95% CI, 22%–37%; I2=99.11%; P=0.00) (Fig. 2), but since the CI of Egger test did not include zero, a significant bias occurred in the publication of the results (coefficient=11.58; T=4.39; P=0.001; 95% CI, 6.23–16.93). The funnel plot is shown in Fig. 3.

Fig. 2.

Fig. 2.

Open in a new tab

Meta-analysis of the global prevalence of Toxocara spp. in pediatric patients.

Fig. 3.

Fig. 3.

Open in a new tab

Publication bias of the prevalence of Toxocara spp. in pediatric patients. CI, confidence interval.

The subgroup analysis by continent showed that the pooled prevalence of Toxocara in pediatric patients in Asia, America, Africa, and Europe was 35% (95% CI, 3%–67%; I2=99.43%; P=0.00), 31% (95% CI, 22%–40%; I2=99.01%; P=0.00), 21% (95% CI, 1%–52%; I2=98.75%; P=0.00), and 26% (95% CI, 19%–34%; I2=85.94%; P=0.00), respectively (Table 2 and Fig. 4).

Table 2.

Pooled prevalence of Toxocara spp. in pediatric patients by continent

Continents Prevalence Between studies
 Between subgroups
I 2 Q Pheterogeneity Q Pheterogeneity
Africa 21% (1–52) 98.75% 80.25 0.001 1.01 0.80
American 31% (22–40) 98.83% 172.82 0.001
Asian 35% (11–58) 98.95% 523.25 0.081
European 21% (1–52) 88.45% 42.67 0.001
Open in a new tab

CI, confidence interval.

Fig. 4.

Fig. 4.

Open in a new tab

Global prevalence (%) of Toxocara spp. in pediatric patients by continent.

1. Meta-regression analysis

We used a meta-regression analysis to assess the effect of suspected variables such as year of study and sample size on heterogeneity. The results of the meta-regression analysis shown in Table 2 did not show any significant association between this variable and the prevalence of Toxocara spp. in pediatric patients (Table 3 and Fig. 5).

Table 3.

Meta-regression analysis to assess the effect of suspected variables on the pooled prevalence of Toxocara spp. in pediatric patients

Prevalence Univariable model
 Multivariable model
β SE P value (95% CI) β SE P value (95% CI)
Toxocara spp. in the pediatrics
 Sample size 0.001 0.0003 0.388 (-0.001 to 0.003) 0.002 0.003 0.370 (-0.001 to 0.003)
 Years of published -0.013 0.008 0.084 (-0.001 to 0.003) -0.014 0.008 0.094 (-0.300 to 0.002)
Open in a new tab

SE, standard error; CI, confidence interval.

Fig. 5.

Fig. 5.

Open in a new tab

Meta-regression graph of the prevalence of Toxocara spp. in pediatric patients by sample size and publication year.

Discussion

Toxocara is a worldwide worm and common intestinal parasite for cats and dogs that have the ability to infect humans [14]. Toxocara can be responsible for a variety of clinical manifestations [14]. The worm’s eggs can pass through the feces of animals and preserve infectivity for a long time in the soil [14]. Soil contamination with Toxoplasma is more frequent in humans [15]. It can be concluded that in some cases, closer contact with animals can increase the exposure risk for this parasite [9,16]. The current study aimed to systematically review the prevalence of Toxocara infection in pediatric patients. The results of 31 relevant studies indicated that the global prevalence of Toxocara in pediatric patients was 30 (95% CI, 22%–37%; I2=99.11%; P=0.00). The prevalence may vary among sample populations and geographical regions.

Oliart-Guzmán et al. [17] investigated the seroprevalence of Toxocara in households with children in Western Brazilian Amazon over 7 years. They concluded that the prevalence of infection in pediatric patients less than 5 years of age was 28%, 23.3%, and 13.9% in 2003, 2010, and 2011, respectively. Oliart-Guzmán et al. [17] suggested that water quality and the treatment of infected animals can be an appropriate strategy for preventing infection in these patients. Roldan et al. [18] investigated eosinophilia and other risk factors of Toxocara infection. They used 2 groups of seropositive and seronegative pediatrics. Their results showed that a dry cough and eosinophilia are significantly associated with Toxocara infection [17].

Serologic techniques are reliable methods that can detect larval antiantigens. The most commonly used serologic test is ELISA testing, which applies the secretion antigens of the parasite larvae [2]. Seroepidemiological evaluations in different countries have shown a global distribution of toxocariasis. The prevalence in American pediatrics is 4.6%–7.3% in the USA, 2.5% in Germany, and 19% in the Netherlands [19]. In Iran, the prevalence among school children was 25.6% in Shiraz and 31% in Ilam [20,21]. Musso et al. [22] reported the association of viral and bacterial central nervous system infections in pediatrics with Toxocara by evaluating the serum and cerebrospinal fluid of 381 patients. Toxocara immunoglobulin G (IgG) was present in 32% of meningitis and 34% of control group patients, a difference that was not statistically significant.

As mentioned above, Toxocara can have a variety of clinical manifestations [14]. Mazur-Melewska et al. [23] evaluated the pulmonary presentation of Toxocara in 119 positive patients who were 1–19 years of age. Their results suggested that high levels of eosinophilia and hyperimmunoglobulinemia E could be related to Toxocara infection. In addition, Pinelli et al. [24] assessed Toxocara infection in patients with suspected VLM and OLM from 1998 to 2009. Their results indicated a significantly decreased rate of infection in the Netherlands that has increased over time as the children grew up.

Epilepsy is a neurological disorder that leads to epileptic seizures [25,26]. Epilepsy can be idiopathic or due to trauma, hypoxia, or infection [27,28]. El-Tantawy et al. [29] assessed Toxocara infection in cryptogenic epilepsy patients. The etiology was unknown in these patients, but brain diseases are mostly suspected. Anti-Toxocara IgG was found in 48% of the cryptogenic epilepsy patients and 46 of the controls, but the difference was not statistically significant [29,30].

Sharghi et al. [31] investigated Toxocara infection as a risk factor for asthma in 95 patients aged 2–15 years and 229 controls. The result showed no statistically significant association between Toxocara and asthma, but Toxocara prevalence showed a significantly higher rate in Hispanic children of Puerto Rican descent. It can be concluded that this race is more susceptible to the disease. In addition, Silva et al. [32] reported the prevalence of Toxocara as a risk factor for atopia and asthma. They reported that the prevalence in northern Brazil is 63% in 791 patients and there is an association between Toxocara infection and serum IgE causing cross-reaction and atopia.

These results show a 35% prevalence of Toxocara infection in Asian pediatrics, a rate that is higher than that in other continents. We assume that the factors responsible for this variation likely represent differences in public health and sanitation status, cultural and social conditions, environmental hygiene, and climate [31,32]. This was a comprehensive meta-analysis of 31 valid publications evaluating 10,676 pediatrics on this topic. Most of the evaluated studies had an appropriate study population. The possibility that some patients were included in more than one report was low. The number of case reports in our assay was low, which leads to a lower risk of publication bias and increases the level of evidence of our findings. The limitations of this study are its high heterogeneity in the pooled estimate, differences in the diagnostic methods, and study population in primary studies.

According to this systematic review and meta-analysis, the global prevalence of Toxocara in pediatrics varies widely among geographical regions. The prevalence of Toxocara in Asian pediatrics was higher than those in other continents, which shows that in this country and in other continents, health policymakers should be more focused on future research and approaches related to Toxocara and other zoonotic diseases, improve the culture, and identify socioeconomically important factors.

Key message

Is the global prevalence of toxocariasis high among children? The prevalence of toxocariasis is high in pediatric patients. Asian children are more susceptible to the disease than other children. Its virulence varies among different socioeconomic classes in various countries. Hand washing after soil contact, routine pet deworming, and appropriate disposal of pet feces in households with Asian pediatrics are needed to prevent toxocariasis.

Footnotes

Conflicts of interest

No potential conflict of interest relevant to this article was reported.

References

  • 1.Macpherson CN. The epidemiology and public health importance of toxocariasis: a zoonosis of global importance. Int J Parasitol. 2013;43:999–1008. doi: 10.1016/j.ijpara.2013.07.004. [DOI] [PubMed] [Google Scholar]
  • 2.Magnaval JF, Glickman LT, Dorchies P, Morassin B. Highlights of human toxocariasis. Korean J Parasitol. 2001;39:1–11. doi: 10.3347/kjp.2001.39.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 3.Schacher JF. A contribution to the life history and larval morphology of Toxocara canis. J Parasitol. 1957;43:599–610. passim. [PubMed] [Google Scholar]
  • 4.Degouy A, Menat C, Aubin F, Piarroux R, Woronoff-Lemsi MC, Humbert P. La toxocarose Toxocariasis. Presse Med. 2001;30(39-40 Pt 1):1933–8. [PubMed] [Google Scholar]
  • 5.Sharma R, Singh BB, Gill JP. Larva migrans in India: veterinary and public health perspectives. J Parasit Dis. 2015;39:604–12. doi: 10.1007/s12639-013-0402-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Buijs J, Borsboom G, van Gemund JJ, Hazebroek A, van Dongen PA, van Knapen F, et al. Toxocara seroprevalence in 5-year-old elementary schoolchildren: relation with allergic asthma. Am J Epidemiol. 1994;140:839–47. doi: 10.1093/oxfordjournals.aje.a117332. [DOI] [PubMed] [Google Scholar]
  • 7.Genchi C, Di Sacco B, Gatti S, Sangalli G, Scaglia M. Epidemiology of human toxocariasis in northern Italy. Parassitologia. 1990;32:313–9. [PubMed] [Google Scholar]
  • 8.MacLean JD, Graeme-Cook FM. Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 12-2002. A 50-year-old man with eosinophilia and fluctuating hepatic lesions. N Engl J Med. 2002;346:1232–9. doi: 10.1056/NEJMcpc020012. [DOI] [PubMed] [Google Scholar]
  • 9.Manini MP, Marchioro AA, Colli CM, Nishi L, Falavigna-Guilherme AL. Association between contamination of public squares and seropositivity for Toxocara spp. in children. Vet Parasitol. 2012;188:48–52. doi: 10.1016/j.vetpar.2012.03.011. [DOI] [PubMed] [Google Scholar]
  • 10.Vandenbroucke JP, von Elm E, Altman DG, Gøtzsche PC, Mulrow CD, Pocock SJ, et al. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration. PLoS Med. 2007;4:e297. doi: 10.1371/journal.pmed.0040297. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11.von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP, et al. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Ann Intern Med. 2007;147:573–7. doi: 10.7326/0003-4819-147-8-200710160-00010. [DOI] [PubMed] [Google Scholar]
  • 12.Moher D, Liberati A, Tetzlaff J, Altman DG, PRISMA Group Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009;6:e1000097. doi: 10.1371/journal.pmed.1000097. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 13.Peterson J, Welch V, Losos M, Tugwell P. The Newcastle-Ottawa scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. Ottawa: Ottawa Hospital Research Institute; 2011. [Google Scholar]
  • 14.Thullier P, Guglielmo V, Rajerison M, Chanteau S. Short report: Serodiagnosis of plague in humans and rats using a rapid test. Am J Trop Med Hyg. 2003;69:450–1. [PubMed] [Google Scholar]
  • 15.Won KY, Kruszon-Moran D, Schantz PM, Jones JL. National seroprevalence and risk factors for Zoonotic Toxocara spp. infection. Am J Trop Med Hyg. 2008;79:552–7. [PubMed] [Google Scholar]
  • 16.Gennari SM, Kasai N, de Jesus Pena HF, Cortez A. Ocorrência de protozoários e helmintos em amostras de fezes de cães e gatos da cidade de São Paulo. Braz J Vet Res Anim Sci. 1999;36:87–91. [Google Scholar]
  • 17.Oliart-Guzmán H, Delfino BM, Martins AC, Mantovani SA, Braña AM, Pereira TM, et al. Epidemiology and control of child toxocariasis in the western Brazilian Amazon - a population-based study. Am J Trop Med Hyg. 2014;90:670–81. doi: 10.4269/ajtmh.13-0506. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Roldán WH, Espinoza YA, Atúncar A, Ortega E, Martinez A, Saravia M. Frequency of eosinophilia and risk factors and their association with Toxocara infection in schoolchildren during a health survey in the north of Lima, Peru. Rev Inst Med Trop Sao Paulo. 2008;50:273–8. doi: 10.1590/s0036-46652008000500005. [DOI] [PubMed] [Google Scholar]
  • 19.Overgaauw PA. Aspects of Toxocara epidemiology: human toxocarosis. Crit Rev Microbiol. 1997;23:215–31. doi: 10.3109/10408419709115137. [DOI] [PubMed] [Google Scholar]
  • 20.Sadjjadi SM, Khosravi M, Mehrabani D, Orya A. Seroprevalence of toxocara infection in school children in Shiraz, southern Iran. J Trop Pediatr. 2000;46:327–30. doi: 10.1093/tropej/46.6.327. [DOI] [PubMed] [Google Scholar]
  • 21.Shokouhi S, Abdi J. Seroprevalence of Toxocara in children from urban and rural areas of Ilam Province, West Iran. Osong Public Health Res Perspect. 2018;9:101–4. doi: 10.24171/j.phrp.2018.9.3.03. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 22.Musso C, Lemos EM, Tsanaclis AM, Pereira FE. Toxocara infection is not associated with viral or bacterial central nervous system infection in children. Neuropediatrics. 2006;37:126–9. doi: 10.1055/s-2006-924511. [DOI] [PubMed] [Google Scholar]
  • 23.Mazur-Melewska K, Jończyk-Potoczna K, Kemnitz P, Mania A, Figlerowicz M, Służewski W. Pulmonary presentation of Toxocara sp. infection in children. Pneumonol Alergol Pol. 2015;83:250–5. doi: 10.5603/PiAP.a2015.0043. [DOI] [PubMed] [Google Scholar]
  • 24.Pinelli E, Herremans T, Harms MG, Hoek D, Kortbeek LM. Toxocara and Ascaris seropositivity among patients suspected of visceral and ocular larva migrans in the Netherlands: trends from 1998 to 2009. Eur J Clin Microbiol Infect Dis. 2011;30:873–9. doi: 10.1007/s10096-011-1170-9. [DOI] [PubMed] [Google Scholar]
  • 25.Fisher RS, Acevedo C, Arzimanoglou A, Bogacz A, Cross JH, Elger CE, et al. ILAE official report: a practical clinical definition of epilepsy. Epilepsia. 2014;55:475–82. doi: 10.1111/epi.12550. [DOI] [PubMed] [Google Scholar]
  • 26.Chang BS, Lowenstein DH. Epilepsy. N Engl J Med. 2003;349:1257–66. doi: 10.1056/NEJMra022308. [DOI] [PubMed] [Google Scholar]
  • 27.Fisher RS, van Emde Boas W, Blume W, Elger C, Genton P, Lee P, et al. Epileptic seizures and epilepsy: definitions proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE) Epilepsia. 2005;46:470–2. doi: 10.1111/j.0013-9580.2005.66104.x. [DOI] [PubMed] [Google Scholar]
  • 28.Hauser WA, Kurland LT. The epidemiology of epilepsy in Rochester, Minnesota, 1935 through 1967. Epilepsia. 1975;16:1–66. doi: 10.1111/j.1528-1157.1975.tb04721.x. [DOI] [PubMed] [Google Scholar]
  • 29.El-Tantawy NL, El-Nahas HA, Salem DAB, Salem NAB, Hasaneen BM. Seroprevalence of Toxoplasma gondii and Toxocara spp. in children with cryptogenic epilepsy. Am J Infect Dis Microbiol. 2013;1:92–5. [Google Scholar]
  • 30.Rostami A, Sepidarkish M, Ma G, Wang T, Ebrahimi M, Fakhri Y, et al. Global prevalence of Toxocara infection in cats. Adv Parasitol. 2020;109:615–39. doi: 10.1016/bs.apar.2020.01.025. [DOI] [PubMed] [Google Scholar]
  • 31.Sharghi N, Schantz PM, Caramico L, Ballas K, Teague BA, Hotez PJ. Environmental exposure to Toxocara as a possible risk factor for asthma: a clinic-based case-control study. Clin Infect Dis. 2001;32:E111–6. doi: 10.1086/319593. [DOI] [PubMed] [Google Scholar]
  • 32.Silva MB, Amor ALM, Santos LN, Galvão AA, Oviedo Vera AV, Silva ES, et al. Risk factors for Toxocara spp. seroprevalence and its association with atopy and asthma phenotypes in school-age children in a small town and semi-rural areas of Northeast Brazil. Acta Trop. 2017;174:158–64. doi: 10.1016/j.actatropica.2016.04.005. [DOI] [PubMed] [Google Scholar]
  • 33.Alonso JM, Bojanich MV, Chamorro M, Gorodner JO. Toxocara seroprevalence in children from a subtropical city in Argentina. Rev Inst Med Trop Sao Paulo. 2000;42:235–7. doi: 10.1590/s0036-46652000000400010. [DOI] [PubMed] [Google Scholar]
  • 34.Aguiar-Santos AM, Andrade LD, Medeiros Z, Chieffi PP, Lescano SZ, Perez EP. Human toxocariasis: frequency of anti-Toxocara antibodies in children and adolescents from an outpatient clinic for lymphatic filariasis in Recife, Northeast Brazil. Rev Inst Med Trop Sao Paulo. 2004;46:81–5. doi: 10.1590/s0036-46652004000200005. [DOI] [PubMed] [Google Scholar]
  • 35.Muradian V, Gennari SM, Glickman LT, Pinheiro SR. Epidemiological aspects of Visceral Larva Migrans in children living at São Remo Community, São Paulo (SP), Brazil. Vet Parasitol. 2005;134:93–7. doi: 10.1016/j.vetpar.2005.05.060. [DOI] [PubMed] [Google Scholar]
  • 36.Paludo ML, Falavigna DL, Elefant GR, Gomes ML, Baggio ML, Amadei LB, et al. Frequency of Toxocara infection in children attended by the health public service of Maringá, south Brazil. Rev Inst Med Trop Sao Paulo. 2007;49:343–8. doi: 10.1590/s0036-46652007000600002. [DOI] [PubMed] [Google Scholar]
  • 37.Nourian AA, Amiri M, Ataeian A, Haniloo A, Mosavinasab SN, Badali H. Seroepidemiological study for toxocariasis among children in Zanjan-northwest of Iran. Pak J Biol Sci. 2008;11:1844–7. doi: 10.3923/pjbs.2008.1844.1847. [DOI] [PubMed] [Google Scholar]
  • 38.Espinoza YA, Huapaya PH, Roldán WH, Jiménez S, Arce Z, Lopez E. Clinical and serological evidence of Toxocara infection in school children from Morrope district, Lambayeque, Peru. Rev Inst Med Trop Sao Paulo. 2008;50:101–5. doi: 10.1590/s0036-46652008000200007. [DOI] [PubMed] [Google Scholar]
  • 39.Zarnowska H, Borecka A, Gawor J, Marczyńska M, Dobosz S, Basiak W. A serological and epidemiological evaluation of risk factors for toxocariasis in children in central Poland. J Helminthol. 2008;82:123–7. doi: 10.1017/S0022149X08912372. [DOI] [PubMed] [Google Scholar]
  • 40.Dar ZA, Tanveer S, Yattoo GN, Sofi BA, Dar PA, Wani SA. Presence of anti-Toxocara antibodies in children population of district Anantnag and Pulwama of Kashmir valley. Indian J Med Microbiol. 2008;26:400–2. doi: 10.4103/0255-0857.43562. [DOI] [PubMed] [Google Scholar]
  • 41.Antonios SN, Eid MM, Khalifa EA, Othman AA. Seroprevalence study of Toxocara canis in selected Egyptian patients. J Egypt Soc Parasitol. 2008;38:313–8. [PubMed] [Google Scholar]
  • 42.Alavi SM, Sefidgaran G. Frequency of anti Toxocara antibodies in schoolchildren with chronic cough and eosinophilia in Ahwaz, Iran, 2006. Pak J Med Sci. 2008;24:360–3. [Google Scholar]
  • 43.Sviben M, Cavlek TV, Missoni EM, Galinović GM. Seroprevalence of Toxocara canis infection among asymptomatic children with eosinophilia in Croatia. J Helminthol. 2009;83:369–71. doi: 10.1017/S0022149X09381213. [DOI] [PubMed] [Google Scholar]
  • 44.Yazar S, Yaman O, Cetinkaya U, Hamamci B, Sahin I. Investigation of anti-Toxocara canis IgG antibodies in patients presenting at The Erciyes University Medical Faculty, Department of Parasitology. Turkiye Parazitol Derg. 2010;34:24–6. [PubMed] [Google Scholar]
  • 45.Santarém VA, Leli FN, Rubinsky-Elefant G, Giuffrida R. Protective and risk factors for toxocariasis in children from two different social classes of Brazil. Rev Inst Med Trop Sao Paulo. 2011;53:66–72. doi: 10.1590/s0036-46652011000200002. [DOI] [PubMed] [Google Scholar]
  • 46.Mattia S, Colli CM, Adami CM, Guilherme GF, Nishi L, Rubinsky-Elefant G, et al. Seroprevalence of Toxocara infection in children and environmental contamination of urban areas in Paraná State, Brazil. J Helminthol. 2012;86:440–5. doi: 10.1017/S0022149X11000666. [DOI] [PubMed] [Google Scholar]
  • 47.Sariego I, Kanobana K, Junco R, Vereecken K, Núñez FA, Polman K, et al. Frequency of antibodies to Toxocara in Cuban schoolchildren. Trop Med Int Health. 2012;17:711–4. doi: 10.1111/j.1365-3156.2012.02996.x. [DOI] [PubMed] [Google Scholar]
  • 48.Schoenardie ER, Scaini CJ, Brod CS, Pepe MS, Villela MM, McBride AJ, et al. Seroprevalence of Toxocara infection in children from southern Brazil. J Parasitol. 2013;99:537–9. doi: 10.1645/GE-3182. [DOI] [PubMed] [Google Scholar]
  • 49.Kanobana K, Vereecken K, Junco Diaz R, Sariego I, Rojas L, Bonet Gorbea M, et al. Toxocara seropositivity, atopy and asthma: a study in Cuban schoolchildren. Trop Med Int Health. 2013;18:403–6. doi: 10.1111/tmi.12073. [DOI] [PubMed] [Google Scholar]
  • 50.Guilherme EV, Marchioro AA, Araujo SM, Falavigna DL, Adami C, Falavigna-Guilherme G, et al. Toxocariasis in children attending a Public Health Service Pneumology Unit in Paraná State, Brazil. Rev Inst Med Trop Sao Paulo. 2013;55:S0036–46652013000300189. doi: 10.1590/S0036-46652013000300009. [DOI] [PubMed] [Google Scholar]
  • 51.Pautova EA, Dovgalev AS, Astanina SIu. Toxocariasis in children and adolescents with allergic and bronchopulmonary diseases, HIV infection, hepatitis B and C risk groups: results of serological screening. Med Parazitol (Mosk) 2013;(2):13–7. [PubMed] [Google Scholar]
  • 52.Mendonça LR, Figueiredo CA, Esquivel R, Fiaccone RL, Pontes-de-Carvalho L, Cooper P, et al. Seroprevalence and risk factors for Toxocara infection in children from an urban large setting in Northeast Brazil. Acta Trop. 2013;128:90–5. doi: 10.1016/j.actatropica.2013.06.018. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 53.Archelli S, Santillan GI, Fonrouge R, Céspedes G, Burgos L, Radman N. Toxocariasis: seroprevalence in abandoned-institutionalized children and infants. Rev Argent Microbiol. 2014;46:3–6. doi: 10.1016/S0325-7541(14)70040-9. [DOI] [PubMed] [Google Scholar]
  • 54.Marchioro AA, Colli CM, Ferreira ÉC, Viol BM, Araújo SM, Falavigna-Guilherme AL. Risk factors associated with toxoplasmosis and toxocariasis in populations of children from nine cities in southern Brazil. J Helminthol. 2015;89:428–32. doi: 10.1017/S0022149X14000212. [DOI] [PubMed] [Google Scholar]
  • 55.Martínez M, García H, Figuera L, González V, Lamas F, López K, et al. Seroprevalence and risk factors of toxocariasis in preschool children in Aragua state, Venezuela. Trans R Soc Trop Med Hyg. 2015;109:579–88. doi: 10.1093/trstmh/trv059. [DOI] [PubMed] [Google Scholar]
  • 56.Cortés NN, Núñez CR, Guiliana BG, García PA, Cárdenas RH. Presence of anti-Toxocara canis antibodies and risk factors in children from the Amecameca and Chalco regions of México. BMC Pediatr. 2015;15:65. doi: 10.1186/s12887-015-0385-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 57.Gabrielli S, Tasić-Otašević S, Ignjatović A, Fraulo M, Trenkić-Božinović M, Momčilović S, et al. Seroprevalence and risk factors for Toxocara canis infection in Serbia during 2015. Foodborne Pathog Dis. 2017;14:43–9. doi: 10.1089/fpd.2016.2190. [DOI] [PubMed] [Google Scholar]
  • 58.Sowemimo OA, Lee YL, Asaolu SO, Chuang TW, Akinwale OP, Badejoko BO, et al. Seroepidemiological study and associated risk factors of Toxocara canis infection among preschool children in Osun State, Nigeria. Acta Trop. 2017;173:85–9. doi: 10.1016/j.actatropica.2017.05.030. [DOI] [PubMed] [Google Scholar]
  • 59.Fialho PMM, Correa CRS, Lescano SZ. Asthma and Seroconversion from Toxocara spp. infection: which comes first? Biomed Res Int. 2018;2018:4280792. doi: 10.1155/2018/4280792. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Clinical and Experimental Pediatrics are provided here courtesy of Korean Pediatric Society

RESOURCES