The 2023 Dengue Outbreak in Bangladesh: An Epidemiological Update

ABSTRACT

Background and Aims

Dengue fever, a mosquito‐borne illness, has emerged as a serious hazard to public health, particularly in tropical and subtropical countries, including Bangladesh. This study aimed to depict an overall scenario of the prevalence of dengue cases and the mortality rate of dengue outbreaks in Bangladesh in 2023.

Methods

From January 1, 2023 to December 31, 2023, day‐to‐day data regarding dengue cases and mortality were collected and compiled from two national databases: the Directorate General of Health Services (DGHS), Ministry of Health and Family Welfare, Bangladesh, and the Institute of Epidemiology, Disease Control, and Research (IEDCR), Bangladesh. Statistical analysis was performed on Microsoft Excel 2021.

Results

Between January 1, 2023 and December 31, 2023, a record number of 321,179 dengue‐infected cases and 1705 deaths (0.53% of total cases) were reported since the very first dengue outbreak in Bangladesh. Males were more infected (n = 192,610, 59.97%), although females had a higher mortality rate (n = 970, 56.89%) compared to males (n = 735, 43.11%). The highest rates of infection (n = 145,571, 45.32%) and death (n = 593, 34.78%) were seen among those under the age group of > 20–40 years. With 79,598 cases (24% of total cases) and 396 deaths (23.23% of all deaths), the month of September recorded the highest peak of the dengue outbreak. Furthermore, Dhaka recorded half of all infected cases (n = 169,321, 52.72%) and the majority (n = 1163, 68.21%) of dengue deaths, according to the division‐wise distribution of cases and deaths.

Conclusion

The findings of the study will be helpful in understanding the dengue situation in Bangladesh and will contribute to further investigations on dengue outbreaks targeting the progression and importance of identifying the circulating DENV serotypes.

1. Introduction

Dengue fever is an acute infectious illness caused by dengue virus (DENV), a member of the family Flaviviridae and is spread from person to person by infected Aedes aegypti mosquitoes [1, 2]. DENV is enveloped and contains a single‐stranded positive‐sense RNA genome, three structural proteins (capsid protein, membrane protein, and envelope protein), and seven nonstructural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4, and NS5) [3]. It has four antigenically different serotypes (DENV 1–4) and all are widely distributed globally [4]. Human infection with any of these four serotypes confers long‐lasting immunity to that particular serotype [5]. Importantly, a novel serotype of dengue virus, DENV‐5, was reported for the very first time in Malaysia in 2013. DENV‐5 spreads predominantly among nonhuman primates and follows the sylvatic circulating cycle compared to the other four serotypes [6]. The particular reason for DENV‐5 transmission is still undetermined; however, genetic shifts from wild animals to humans, a significant number of mutations within the DENV genome, and substantial deforestation may have led to the emergence of the virus [6, 7]. Human dengue virus infection is typically asymptomatic, but symptomatic infections can vary in severity from a low fever to life‐threatening hemorrhagic fever and/or shock syndrome [2], characterized by a decrease in platelets, white blood cells, and an increase in vascular permeability [8].

Dengue fever is considered an emerging risk because of an increase in mortality related to the disease's increased severity, which may be driven by viral adaptations [9]. According to the World Health Organization (WHO) about 50–100 million dengue cases are reported worldwide each year, with severe illnesses on the rise in Southeast Asia, Africa, South America, and the Western Pacific countries [10]. 70% of dengue cases occur in endemic areas of tropical and subtropical nations, including South East Asia and South Asia (https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue). Importantly, dengue is more prevalent in low and middle‐income countries due to increased population densities, inadequate healthcare systems, fast unplanned urbanization, and changing climatic conditions [11].

Bangladesh is a highly populated South Asian country with a population of over 165 million and is reported as a dengue‐endemic country [12]. Between 1964 and 1999, there were infrequent reports of dengue in Bangladesh, before the first major outbreak in 2000, when 5551 hospitalized cases and 93 deaths were recorded [12, 13, 14]. After that dengue fever has become an endemic in the country, causing a significant number of infections and impacting the population's quality of life [12]. According to available hospital‐based surveillance data, over 5000 hospitalized dengue cases were recorded between 2000 and 2022 in Dhaka city, the capital, which was considered as the epicentre of seven major dengue outbreaks that occurred within the period (2000–2022) [15]. The Bangladesh National Health Accounts (BNHA) reports that the dengue crisis in Bangladesh is putting a financial strain on our health system, just like it is in other lower and middle‐income countries [16]. Multiple risk factors are highly associated with the recent major dengue outbreaks in the country. In fact, if suitable prevention efforts are not implemented, poor healthcare infrastructure, insufficient outbreak preparation, and a lack of community‐level knowledge of dengue infection may result in public health crises [12]. A more accurate assessment of the disease's incidence and fatality rate during the previous years may help in the proper diagnosis and control of future dengue outbreaks in Bangladesh.

Since the very first dengue outbreak in 2000 [12], Bangladesh has had the worst dengue outbreak on record in 2023. The health system was under tremendous pressure as a result of this outbreak. In this regard, the study aimed to depict an overall scenario of the dengue outbreak in Bangladesh in 2023.

2. Methodology

Day‐to‐day data regarding dengue cases and mortality were collected and compiled from two national databases: the Directorate General of Health Services (DGHS), Ministry of Health and Family Welfare, Bangladesh (https://old.dghs.gov.bd/index.php/bd/), and the Institute of Epidemiology, Disease Control, and Research (IEDCR), Bangladesh (https://iedcr.gov.bd/). These two online‐based national databases update information regarding the day‐to‐day dengue situation, including new cases and deaths from the government tertiary hospitals, clinics, and health complexes at the divisional and district levels of Bangladesh. The dengue cases were confirmed by the NS1 antigen test and associated clinical symptoms evaluated by the healthcare professionals in these healthcare facilities. These two online‐based national databases were chosen for data collection on nationwide surveillance on dengue infections for cross‐checking purposes while the daily recorded cases and deaths were congruent with one another. Moreover, the 2023 prior data set on dengue infections was only available in one of the two national databases (https://iedcr.gov.bd/). So, for sharing the comprehensive scenario on the dengue situation in Bangladesh in 2023 and previous years, two online‐based national databases were chosen. Statistical analysis was performed on Microsoft Excel 2021.

3. Results

The month‐wise distribution of dengue cases and deaths in Bangladesh in 2023 is illustrated in Figure 1. Though 111 dengue cases were recorded in the month of March, no deaths were found. From the month of June, the infection rate (n = 5956, 1.85%) and deaths (n = 34, 1.99%) began to rise, pointing out that dengue infection may increase due to the rainy season. The rate of infection and deaths reached its peak in the month of September, with 79,598 (24.78%) cases and 396 (23.23%) deaths. Majority of total cases (68.29%) and deaths (64.34%) were recorded in the month of August, September, and October. These 3 months were identified as the deadliest period for spreading dengue infection in Bangladesh in 2023. From the month of November, the scenario began to decline, pointing out that dengue severity may decrease due to the winter season in Bangladesh (Figure 1).

Figure 1.

Month‐wise distribution of dengue cases and deaths in Bangladesh (January 1, 2023–December 31, 2023).

Figure 2 represents the rate of dengue infection and mortality in males and females from January 1, 2023 to December 31, 2023. Of 321,179 dengue cases, 59.97% (n = 192,610) were male and 40.03% (n = 128,569) were female (Figure 2A). In addition, among 1705 dengue deaths, 43.11% (n = 735) and 56.89% (n = 970) were male and female, respectively (Figure 2B).

Figure 2.

Infection and mortality rate in male and female dengue cases in Bangladesh (January 1, 2023–December 31, 2023).

The study found that of 321,179 cases, people with > 20–40 years age group were infected mostly (n = 145,571, 45.32%) followed by > 40–60 years (n = 64,373, 20.04%), > 10–20 years (n = 60,724, 18.91%), > 60–80 years (n = 17,226, 5.36%), > 5–10 years (n = 16,209, 5.05%), <= 5 years (n = 16,019, 4.99%) and more than 80 years (n = 1057 0.33%) in Bangladesh (Figure 3). In addition, of 1705 deaths (0.53% of total cases) due to dengue infection, the highest mortality rate was found in > 20–40 years age group (n = 593, 34.78%), followed by > 40–60 years age group (n = 528, 30.97%), > 60–80 years (n = 280, 16.42%), > 10–20 years (n = 144, 8.45%), <= 5 years (n = 66, 3.87%), > 5–10 years (n = 58, 3.40%) and > 80 years age group (n = 36, 2.11%) (Figure 3).

Figure 3.

Dengue cases and deaths among different age groups in Bangladesh (January 1, 2023–December 31, 2023).

Figure 4 shows the division‐wise distribution of dengue‐infected cases and deaths in Bangladesh in 2023. Dhaka, the capital and most populated division of Bangladesh, was the hardest hit by the dengue epidemic ever recorded, with half of the total cases (n = 169,321, 52.72%) and the majority (n = 1163, 68.21%) of total deaths in Bangladesh in 2023. More specifically, only the Dhaka city area (excluding outside of the city and other districts of Dhaka division) was recorded with 110,008 dengue cases (34.25% of total cases) and 980 deaths (57.48% of total deaths). Followed by the Dhaka division, the Chittagong division experienced the second highest dengue infection (n = 44,435, 13.83%). On the other hand, the Barisal division was found to have the second highest number of deaths (n = 206, 12.08%). But there were no dengue deaths in these two Bangladeshi divisions. The Sylhet division was recorded with the lowest rate of dengue‐confirmed cases (n = 1435, 0.45%) and deaths (n = 1, 0.06%) (Figure 4).

Figure 4.

Division‐wise distribution of dengue cases and deaths during the 2023 dengue outbreak in Bangladesh (January 1, 2023–December 31, 2023). The image of Bangladesh's map was used from the study of CM Rossignoli et al. [17].

The status of month‐ and year‐wise dengue‐infected cases in the last 10 years (from 2014 to 2023) in Bangladesh is represented in Table 1. A total of 535,970 dengue cases were recorded in the last 10 years (2014–2023) in Bangladesh. In 2014, approximately 375 dengue cases were documented, accounting for 0.07% of total cases. Then the cases began to increase annually, except in 2017. But interestingly, due to the COVID‐19 pandemic, dengue fever in Bangladesh dropped dramatically in 2020 after 2019's unprecedented spike in dengue cases (101,354 cases, 18.91% of total cases in the last 10 years). In 2022, when the COVID‐19 pandemic began to decrease in Bangladesh, dengue cases began to rise (n = 61,089, 11.40% of total cases from 2014 to 2023). Then, in 2023, the country experienced the deadliest scenario of the dengue epidemic in the country. More than half of the total dengue confirmed cases from 2014 to 2023 were recorded in the last year (2023), with the highest ever cases (n = 321,179, 59.92% of total cases) in Bangladesh, breaking down the previous record of dengue epidemic in the country in 2019 (Table 1). In addition, Table 2 shows the mortality history due to dengue infections in the last 10 years (2014–2023) in Bangladesh. In 2014, no death was recorded. From 2015, the deaths due to dengue infection began to rise, except in 2017 (n = 8) and 2020 (n = 3). In 2019, during the first major outbreak in the country, 164 (0.16%) deaths were reported. In 2023, the highest number of death cases (n = 1705) with a 0.53% mortality rate based on the total reported dengue cases (n = 321,179) was recorded.

Table 1.

Status on month and year‐wise dengue‐infected cases in the last 10 years (from 2014 to 2023) in Bangladesh.

Years	Months												Total cases, n ***	Infection rate (%)****
	January	February	March	April	May	June	July	August	September	October	November	December
2014	15	7	2	0	8	9	82	80	76	63	22	11	375	0.07
2015	0	0	2	6	10	28	171	765	965	869	271	75	3162	0.59
2016	13	3	17	38	70	254	926	1451	1544	1077	522	145	6060	1.13
2017	92	58	36	73	134	267	286	346	430	512	409	126	2769	0.52
2018	26	7	19	29	52	295	946	1796	3087	2406	1192	293	10,148	1.89
2019	38	18	17	58	193	1884	16,253	52,636	16,856	8143	4011	1247	101,354	18.91
2020	199	45	27	25	10	20	23	68	47	164	546	231	1405	0.26
2021	32	9	13	3	43	272	2286	7698	7841	5458	3567	1207	28,429	5.30
2022	126	20	20	23	163	737	1571	3521	9911	21,932	19,334	3731	61,089	11.40
2023	566	166	111	143	1036	5956	43,854	71,976	79,598	67,769	40,716	9288	321,179	59.92
Total cases, n *	1107	333	264	398	1719	9722	66,398	140,337	120,355	108,393	70,590	16,354	535,970
Infection rate (%)**	0.21	0.06	0.05	0.07	0.32	1.81	12.39	26.18	22.46	20.22	13.17	3.05

Note: The bold value 59.92 indicates the highest ever dengue infection rate (%) was recorded in 2023 within the timeframe of 2014–2023. The bold value 26.18 indicates the highest ever dengue infection rate (%) was recorded in the month of August within the timeframe of 2014–2023.

^*Month‐wise from 2014 to 2023.

^**Month‐wise dengue infection rate from 2014 to 2023.

^***Year‐wise total dengue cases.

^****Year‐wise dengue infection rate (%) based on the total cases from 2014 to 2023.

Table 2.

Mortality history due to dengue infections in the last 10 years (from 2014 to 2023) in Bangladesh.

Year	No. of deaths	Mortality rate (%) based on the yearly dengue cases	Mortality rate (%) based on the total deaths (n = 2300) (2014–2023)
2014	0	0.00	0.00
2015	6	0.19	0.26
2016	14	0.23	0.61
2017	8	0.29	0.35
2018	26	0.26	1.13
2019	164	0.16	7.13
2020	3	0.21	0.13
2021	105	0.37	4.57
2022	269	0.44	11.70
2023	1705	0.53	74.13

From 2014 to 2023, the month of August was recorded as the deadliest month for dengue infection throughout the country, with 140,337 cases (26.18%). From July to October, this period was documented as the most vulnerable to a dengue outbreak in Bangladesh, with 435,483 dengue cases, which accounts for 81.25% of the total dengue cases in the country based on the total dengue cases in the last 10 years. Importantly, the frequency of dengue fever cases increases in the month of May and declines in the month of November in Bangladesh, pointing out that the winter seasons may reduce the spread of dengue infection in the country (Table 1).

4. Discussion

Due to the rapidly spreading geographic range of vector infestation, dengue virus infection is regarded as a serious public health risk [18]. Given that the frequency of the dengue illness has grown by a factor of 30 over the past 50 years, more than half of the world's population currently lives in dengue‐endemic areas in more than 100 different countries [19]. Dengue incidence was reported occasionally in Bangladesh between 1964 and 1999, until the first significant epidemic in 2000, when 5551 people were hospitalized and 93 people died [13, 14]. Dengue infections resurfaced in 2016 (6060 cases and 14 deaths) and reached its peak in 2019 with 101,354 cases and 164 deaths in the country. But this outbreak declined in 2020, with just 1405 cases and 3 deaths, which the COVID‐19 pandemic could mask the dengue infections. In 2021, the frequency of cases (n = 28,429) and mortality (n = 105) increased, followed by another significant outbreak in 2022 with 61,732 cases and 281 deaths [15]. Then, in 2023, the country faced the deadliest scenario of the dengue outbreak. More than half (n = 321,179, 59.92% of total cases) of all dengue confirmed cases in Bangladesh in the last 10 years (2014–2023) were reported in Bangladesh in 2023, breaking the previous record of dengue epidemic in the country (Table 1). This statistic demonstrates the severity of dengue outbreaks in Bangladesh.

However, in all dengue epidemics documented in Bangladesh, the gender distribution revealed a strong male predominance. The study showed that male cases were more frequent than females (Figure 2A), but in the case of mortality, females were predominant (Figure 2B). Similarly, a comprehensive review study reported similar findings that the proportion of male cases was almost double compared to females in all previous dengue outbreaks in Bangladesh, where the male‐to‐female ratio was as high as 2.7 [12]. Even though most research from India found a male majority, a few investigations showed a varied distribution [20]. Six other culturally and economically varied Asian nations reported a large male surplus in their teenage and adult populations [21]. In contrast, the frequency of female dengue‐infected cases was similar to or higher than that of male cases in South America [22]. Some potential factors can contribute to the varied male‐to‐female ratios in dengue infection. Due to the fact that the majority of the studies were conducted in hospitals and that male patients are more common in underdeveloped nations like Bangladesh, this discrepancy may be the result of case selection bias [12]. In fact, females are generally less likely to get medical care for dengue symptoms, possibly leading to underreporting and contributing to the variation in the frequency of male–female dengue‐infected cases. In addition, males are more likely to contract dengue than females because of their activity and exposure trends. Working‐age males are more prone to spend their days outside during peak mosquito biting hours [23, 24].

During the dengue epidemic in Bangladesh in the last year, analysis of the incidence of dengue cases and fatalities across all age categories showed that dengue infection affected people of all ages, from under 5 to over 80. In this study, majority of the dengue cases were in the > 20–40 age group (Figure 3). According to earlier research, dengue mostly affected young adults in Bangladesh [21]. More than 80% of patients during the initial pandemic in 2000 were adults (> 18 years of age); the greatest age range for cases was 18–33 years of age [21]. Similarly, in the 2002 dengue outbreak, the majority (62%) of the cases were 16–30 years old (mean age 29 years) [25]. In addition, in the 2016 (21–40; 55%), 2018 (15–29; 65%), and 2019 (21–40; 50%) outbreaks, older adolescents and young adults accounted for the majority of cases [26, 27, 28]. A similar outcome was observed in the 2018 dengue outbreak in Sri Lanka [29]. Studies in several places in India also showed a high prevalence of young adults [20]. However, besides young adults, children are also a more vulnerable group to dengue infection. In the 2023 dengue outbreak in Bangladesh, 10.04% of the total cases were in the <= 5–10 year age group. During the 2019 dengue epidemic, a hospital‐based survey reported that the majority (46.1%) of children were between the ages of 10 and 14 (mean age of 8.8 years) [30]. In fact, children over 6 years old are more likely to be exposed to infected mosquitoes, possibly due to their increased time in crowded areas throughout primary school [31]. So, the severity of the illness also varies by age.

However, it is reported that rainfall is directly correlated with Aedes aegypti vector abundance because it creates ideal conditions for breeding and egg hatching [32]. In addition, mosquito survival, reproduction, and viral transmissibility are all influenced by temperature [32]. Aedes species mosquitoes are particularly temperature‐sensitive, with an ideal temperature range between 23°C and 29°C [33]. Notably, Bangladesh's climate is very similar throughout the country, with summertime the average of daily mean temperatures ranging from 22°C to 33°C in all areas (March to October). This makes the country the ideal place for dengue to proliferate [34]. In addition, since Aedes aegypti is a hydrophilic species, the risk of dengue outbreaks is significantly increased with the combination of humidity, rainfall, and temperature [5]. Bangladesh has a subtropical monsoon climate with significant seasonal fluctuations in temperature, rainfall, and humidity (https://www.weatheronline.co.uk/reports/climate/bangladesh.htm). Thus, the climate of Bangladesh is ideal for vector breeding and viral transmission, making the country vulnerable to vector‐borne diseases such as dengue. This study showed that in 2023, the dengue infection rate and fatalities began to rise in June, highlighting that dengue infection may increase all over the rainy season. The infection and mortality rates peaked in September. August, September, and October accounted for over one‐third of all cases and more than half of all fatalities, indicating them as the most critical period for spreading dengue infection in Bangladesh. However, the conditions began to decline in November due to the cold weather in Bangladesh (Figure 1).

According to this study, August was the worst month for dengue outbreaks in the country, with the highest infection rate (26.18%) in the last decade (2014–2023). Importantly, from July to October, this period was found to be the most vulnerable to a dengue epidemic in the country. Moreover, the incidence of dengue fever cases in Bangladesh increases in May and decreases in November, indicating that the winter months may slow the spread of dengue infection (Table 1). However, from 2010 to 2021, most dengue cases were reported in Bangladesh during the monsoon season (June–September) and the post‐monsoon season (October–November), with a greater incidence peak in September [12]. During the 2022 outbreak, infections peaked in October [12]. Additionally, in case of mortality between 2014 and 2023, 164 deaths were reported in 2019, during the first major dengue outbreak in the country. In 2023, the highest mortality rate based on the total reported dengue cases was recorded in Bangladesh. Notably, 97.56% of total recorded deaths (2014–2023) were found between 2019 and 2023 (Table 2). A latest research has suggested that due to Bangladesh's frequently shifting environment, dengue transmission might become year‐round by the end of the 21st century [35].

However, dengue's geographic expansion depends on environmental and climate‐related factors, population density, and the availability and adaptation of mosquito vector species and viruses [36]. In addition, urbanization is thought to play a vital role in the transmission of diseases carried by mosquitoes as it encourages geographical dispersal, produces mosquito breeding sites, and raises the possibility of vector‐human contact [11]. Importantly, Bangladesh is experiencing fast and uncontrolled urbanization in all of its outlying district towns [37]. For example, in just two decades, one of the least developed district towns has experienced nearly 600% urbanization. Due to increased urbanization, dengue is hyperendemic in Dhaka city, the capital of Bangladesh [12]. According to this study, in the 2023 dengue outbreak, Dhaka division, including the Dhaka city and outside of the city area or districts of Dhaka division, was affected the worst by the dengue infections ever recorded, accounting for half of all cases (52.72%) and the majority (68.21%) of all deaths. From 2000 to 2018, Dhaka experienced 90% of dengue outbreaks and fatalities [38]. However, three subsequent outbreaks in 2019, 2021, and 2022 have highlighted the expansion of dengue fever in non‐endemic locations. During the 2019 epidemic, 48.4% of cases were recorded from all 64 districts in Bangladesh [12]. In 2021, 20.4% of cases were reported outside of Dhaka, similar to previous outbreaks (https://old.dghs.gov.bd/index.php/bd/home/5200-daily-dengue-status-report). During the 2022 epidemic, more than one‐third of infections were reported outside Dhaka. But the severity of the 2021 epidemic (28,429 cases and 105 fatalities) was uncertain due to the COVID‐19 pandemic [12]. This study also reported that following Dhaka, Chittagong division and the Barisal division became two new hotspots of dengue transmission in 2023. On the other hand, Sylhet division had the lowest number of confirmed dengue cases (0.45%) and deaths (0.06%) (Figure 4). However, it is unclear if the district‐level dengue infections were transmitted locally or had a travel history from Dhaka to other districts. Traveling from Dhaka to the outer districts might spread virus‐carrying mosquitoes to peripheral districts. Importantly, the increased frequency of dengue infections outside Dhaka division remained consistent throughout the outbreak, indicating local dengue transmission [12]. A recent study showed the local transmission of dengue in a northern region of Bangladesh in the 2019 dengue outbreak [39]. So, dengue infection is spreading to non‐endemic places in Bangladesh.

Notably, Bangladesh is experiencing fast and unplanned urbanization, and this is an important driver of mosquito‐borne diseases because it provides mosquito breeding sites, enhances the possibility of vector‐human contact, and facilitates regional spreading [37]. Besides, the expansion of dengue from an endemic centre to non‐endemic areas will have a significant impact on the country's inadequate healthcare system [40], because the district‐level healthcare facilities in Bangladesh's non‐endemic regions lack the resources they need to handle major dengue crises. If dengue outbreaks become extensive or coincide with other viral epidemics, the country's current healthcare system might collapse [15]. However, one of the most important elements of the dengue preventive approach is community empowerment. To create a sustainable dengue mitigation plan, social and ecological elements must be taken into account. In addition, public–private partnerships can play an important role in implementing the dengue mitigation strategy because the government cannot do it alone effectively [12].

5. Limitations

Though this study tried to provide a comprehensive scenario for the 2023 dengue outbreak in Bangladesh, it has some limitations. As the data were collected from two national online databases focusing on only hospital‐reported cases and related mortality, there is a possibility that dengue cases and fatalities were underrepresented. Furthermore, we were unable to include data from laboratory‐based findings, such as real‐time reverse transcription polymerase chain reaction (RT‐PCR) for dengue serotyping or any serological analysis. Furthermore, this study didn't employ a systematic review approach, and its search method was not extensive. Importantly, the data were not processed with IBM SPSS or GraphPad Prism software. The statistical analysis was carried out using only Microsoft Excel 2021.

6. Conclusion

This study provides an overview of the latest dengue outbreak in Bangladesh in 2023. This study's findings will contribute to future research on dengue epidemics in Bangladesh. To comprehend the whole picture of the country's dengue outbreak, we recommend that all hospitals, clinics, and diagnostic labs in Dhaka and at the district level be included in the countrywide dengue monitoring system. Furthermore, community involvement should be increased to tackle this disease every year.

Author Contributions

Mohabbat Hossain: conceptualization, methodology, data curation, validation, formal analysis, visualization, writing – original draft, writing – review and editing. Md Shafiqul Islam Rakib: methodology, writing – original draft. Md Mahedi Hasan: methodology, writing – original draft. Shams Nur Powshi: methodology, writing – original draft. Enayetul Islam: methodology, writing – original draft. Nazneen Naher Islam: conceptualization, supervision, resources, writing – review and editing.

Conflicts of Interest

The authors declare no conflicts of interest.

Transparency Statement

The lead author Mohabbat Hossain and Nazneen Naher Islam affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

Data Availability Statement

The data that support the findings of this study are available in Directorate General of Health Services (DGHS), Bangladesh at https://old.dghs.gov.bd/index.php/bd/. These data were derived from the following resources available in the public domain: Directorate General of Health Services (DGHS), Bangladesh, https://old.dghs.gov.bd/index.php/bd/—Institute of Epidemiology, Disease Control, and Research, https://www.iedcr.gov.bd/. The raw data were collected from the public database (https://old.dghs.gov.bd/index.php/bd/, https://iedcr.gov.bd/) and will also be available from the corresponding author on request.