Changing characteristics of rotavirus diarrhea in children younger than five years in urban Bangladesh

Prevalence and genetic diversity of rotavirus in Bangladesh during pre-vaccination period, 1973-2023: a meta-analysis

Introduction

Rotavirus infection is a major cause of mortality among children under 5 years in Bangladesh. There is lack of integrated studies on rotavirus prevalence and genetic diversity during 1973 to 2023 in Bangladesh.

Methods

This meta-analysis was conducted to determine the prevalence, genotypic diversity and seasonal distribution of rotavirus during pre-vaccination period in Bangladesh. This study included published articles on rotavirus A, rotavirus B and rotavirus C. We used Medline, Scopus and Google Scholar for published articles. Selected literatures were published between 1973 to 2023.

Results

This study detected 12431 research articles published on rotavirus. Based on the inclusion criteria, 29 of 75 (30.2%) studies were selected. Molecular epidemiological data was taken from 29 articles, prevalence data from 29 articles, and clinical symptoms from 19 articles. The pooled prevalence of rotavirus was 30.1% (95% CI: 22%-45%, p = 0.005). Rotavirus G1 (27.1%, 2228 of 8219) was the most prevalent followed by G2 (21.09%, 1733 of 8219), G4 (11.58%, 952 of 8219), G9 (9.37%, 770 of 8219), G12 (8.48%, 697 of 8219), and G3 (2.79%, 229 of 8219), respectively. Genotype P[8] (40.6%, 2548 of 6274) was the most prevalent followed by P[4] (12.4%, 777 of 6274) and P[6] (6.4%, 400 of 6274), respectively. Rotavirus G1P[8] (19%) was the most frequent followed by G2P [4] (9.4%), G12P[8] (7.2%), and G9P[8], respectively. Rotavirus infection had higher odds of occurrence during December and February (aOR: 2.86, 95% CI: 2.43-3.6, p = 0.001).

Discussion

This is the first meta-analysis including all the studies on prevalence, molecular epidemiology, and genetic diversity of rotavirus from 1973 to 2023, pre-vaccination period in Bangladesh. This study will provide overall scenario of rotavirus genetic diversity and seasonality during pre-vaccination period and aids in policy making for rotavirus vaccination program in Bangladesh. This work will add valuable knowledge for vaccination against rotavirus and compare the data after starting vaccination in Bangladesh.

Changing Water-Sanitation Determinants of Cholera over Two Decades in Bangladesh

Cholera is a leading global public health threat, especially in developing countries. This study aimed to determine the changing determinants of cholera related to water-sanitation practices between 1994-1998 and 2014-2018 in Dhaka, Bangladesh. Data of all cause diarrhea cases were extracted from the Diarrheal Disease Surveillance System of the International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, and analysis was performed among three groups: Vibrio cholerae detected as sole pathogen, V. cholerae detected as mixed infection, and detection of no common enteropathogen in stool specimens (reference). Using sanitary toilet, drinking tap water, drinking boiled water, family size greater than five, and slum dwelling were the main exposures. Overall, 3,380 (20.30%) and 1,290 (9.69%) patients were positive for V. cholerae during 1994-1998 and 2014-2018, respectively. In 1994-1998, use of sanitary toilet (adjusted odds ratio [aOR]: 0.86, 95% CI: 0.76-0.97) and drinking tap water (aOR: 0.81, 95% CI: 0.72-0.92) were found to be negatively associated and in 2014-2018, drinking tap water (aOR: 1.47, 95% CI: 1.21-1.78) and slum dwelling (aOR: 1.43, 95% CI: 1.10-1.86) were found to be positively associated with V. cholerae infection after adjusting for age, sex, monthly income, and seasonality. Because the determinants of cholera such as drinking tap water can change over time in developing cities, ameliorating the water, sanitation, and hygiene (WASH) situation is of paramount importance. In addition, in settings such as urban slums, where long-term WASH monitoring might be difficult to achieve, mass vaccination with oral cholera vaccine should be introduced to control cholera.

Burden of Shigella in South Asia: a systematic review and meta-analysis

BACKGROUND

Shigella remains one of the most common causes of diarrhoea in South Asia. Current estimates of the prevalence of Shigella are critical for guiding control measures. We estimated the prevalence of Shigella species and serogroups in South Asia.

METHODS

We performed a systematic review using PubMed, EMBASE, Google Scholar and Web of Science for peer-reviewed studies published between 2000 and 19 June 2022. We also manually searched the reference lists of the reviewed studies to identify additional studies. We included studies that detected the presence of Shigella in stool by culture or polymerase chain reaction (PCR). Studies associated with outbreaks were excluded. Two investigators independently reviewed the studies, extracted the data and performed quality assessment. A random-effects meta-analysis was performed to determine the pooled prevalence of Shigella.

RESULTS

Our search yielded 5707 studies, of which 91 studies from five South Asian countries were included in the systematic review, 79 in the meta-analysis of Shigella prevalence and 63 in the meta-analysis of Shigella serogroups prevalence. The pooled prevalence of Shigella was 7% [95% confidence interval (CI): 6-7%], with heterogeneity (I2 = 98.7; P < 0.01). The prevalence of Shigella was higher in children aged <5 years (10%; 95% CI: 8-11%), in rural areas (12%; 95% CI: 10-14%) and in studies using PCR (15%; 95% CI: 11-19%). Shigella flexneri (58%) was the most abundant serogroup, followed by Shigella sonnei (19%), Shigella boydii (10%) and Shigella dysenteriae (9%). Shigella flexneri 2a was the most frequently isolated serotype (36%), followed by serotype 3a (12%), serotype 6 (12%) and serotype 1b (6%). The prevalence of non-typeable Shigella was 10.0%.

CONCLUSIONS

Although the prevalence of Shigella in South Asia remains generally high, it varies by age group and geographical area, with data lacking in some countries. Effective Shigella vaccines would be advantageous for both endemic communities and travellers.

The influence of demographic and meteorological factors on temporal patterns of rotavirus infection in Dhaka, Bangladesh

To quantify the potential impact of rotavirus vaccines and identify strategies to improve vaccine performance in Bangladesh, a better understanding of the drivers of pre-vaccination rotavirus patterns is required. We developed and fitted mathematical models to 23 years (1990-2012) of weekly rotavirus surveillance data from Dhaka with and without incorporating long-term and seasonal variation in the birth rate and meteorological factors. We performed external model validation using data between 2013 and 2019 from the regions of Dhaka and Matlab. The models showed good agreement with the observed age distribution of rotavirus cases and captured the observed shift in seasonal patterns of rotavirus hospitalizations from biannual to annual peaks. The declining long-term trend in the birth rate in Bangladesh was the key driver of the observed shift from biannual to annual winter rotavirus patterns. Meteorological indices were also important: a 1°C, 1% and 1 mm increase in diurnal temperature range, surface water presence and degree of wetness were associated with a 19%, 3.9% and 0.6% increase in the transmission rate, respectively. The model demonstrated reasonable predictions for both Dhaka and Matlab, and can be used to evaluate the impact of rotavirus vaccination in Bangladesh against changing patterns of disease incidence.

Characteristics of Rotavirus, ETEC, and Vibrio Cholerae Among Under 2-year Children Attending an Urban Diarrheal Disease Hospital in Bangladesh

Background

Information on comparative clinical and host characteristics of under-2 children with watery diarrhea caused by rotavirus, Enterotoxigenic Escherichia coli (ETEC), and Vibrio cholerae as single pathogens is lacking. We sought to investigate the sociodemographic, clinical, and host characteristics of under-2 children hospitalized due to these pathogens.

Methodology

We conducted a hospital-based case-control study using the icddr,b Diarrheal Diseases Surveillance System. Children of either sex, <2 years with diarrhea, who attended the hospital during 2014 to 2018, constituted the study population. Stool specimens having a single pathogen like rotavirus, ETEC, or Vibrio cholerae constituted the cases and stool specimens having no detectable common enteropathogens comprised the controls. Multinomial logistic regression analysis was done where control was the reference group.

Results

A total of 14 889 patients were enrolled, 6939 of whom were under-2 children, and 5245 (76%) constituted our study population. Among them 48% (n = 2532), 3% (n = 148) and 1% (n = 49) had rotavirus, ETEC, and Vibrio cholera, respectively. A control group (diarrhea without these 3 or Shigella, Salmonella, Aeromonas) accounted for 48% (n = 2516). In multinomial regression model, children with rotavirus (adjusted odds ratio [aOR], 1.36; 95% confidence interval [95% CI], 1.19-1.55) less often presented with dehydrating diarrhea compared to those with ETEC (aOR, 1.54; 95% CI, 1.05-2.26) and cholera (aOR, 2.25; 95% CI, 1.11-4.57). Rotavirus diarrhea was associated (aOR, 1.25; 95% CI, 1.07-1.46) with those who received antimicrobials prior to hospital admission and protectively associated with drinking tap water (aOR, 0.84; 95% CI, 0.73-0.95); however, ETEC diarrhea had protective association (aOR, 0.62; 95% CI, 0.43-0.92) with children who received antimicrobials prior to hospital admission and was associated with drinking tap water (aOR, 1.78; 95% CI, 1.19-2.66). Use of intravenous fluid was associated with cholera (aOR, 10.36; 95% CI, 4.85-22.16) and had protective association with rotavirus episodes (aOR, 0.64; 95% CI, 0.45-0.91).

Conclusions

Clinical presentations and host characteristics of rotavirus, ETEC, and Vibrio cholerae diarrhea differed from each other and the information may be helpful for clinicians for better understanding and proper management of these children.

Bangladesh: a success case in combating childhood diarrhoea

BACKGROUND

Bangladesh had a large reduction in childhood deaths due to diarrhoeal disease in recent decades. This paper explores the preventive, promotive, curative and contextual drivers that helped Bangladesh achieve this exemplary success.

METHODS

Primary and secondary data collection approaches were used to document trends in reduction of Diarrhoea Specific Mortality Rate (DSMR) between 1980 and 2015, understand what policies and programmes played key roles, and estimate the contribution of specific interventions that were implemented during the period. Data acquisition involved relevant document reviews and in-depth interviews with key stake-holders. A systematic search of literature was undertaken to explore socio-economic, aetiological, behavioural, and nutritional drivers of diarrhoeal disease reduction in Bangladesh. Finally, we used LiST (Lives Saved Tool) to model the contributions of the relevant interventions during three time periods (1980-2015, 1980-2000 and 2000-2015), and to project the number of lives saved in 2030 (compared to 2015) if these interventions were implemented at near universal coverage (90%).

RESULTS

The factors which likely had the most impact on DSMR were the coordinated efforts of the Government of Bangladesh (GoB) with non-government organizations (NGOs) and the private sector that enabled swift implementation, at scale, of interventions like oral rehydration solution (ORS) and zinc, promotion of breastfeeding, handwashing and sanitary latrines (WASH), as well as improvements in female education and nutrition. Compared to 1980, we found ORS and reduction in stunting prevalence had the greatest impact on DSMR, saving roughly 70 000 lives combined in 2015. Until 2000, ORS had a higher contribution to DSMR reduction than reduction in stunting prevalence. This proportionate contribution was reversed during 2000-2015. At near universal coverage (90%) of combined direct diarrhoeal disease, nutrition and WASH interventions, we project that an additional 5356 deaths due to diarrhoea could be averted in 2030.

CONCLUSION

Bangladesh's achievement in reduction of DSMR highlights the important role of an enabling policy environment that fostered coordinated efforts of the public and private sectors and NGOs for maximal impact. To maintain this momentum, evidence-based interventions should be scaled up at universal coverage.

Vibrio cholera and V. parahaemolyticus coinfection in an oncology patient with gastroenteritis

Vibrio-related gastroenteritis in the United States is mostly associated with the consumption of raw or improperly cooked seafood. We describe a case of a stage IV lung adenocarcinoma patient who became ill after eating crab while visiting Upstate New York. Molecular testing and culture confirmed a coinfection with V. parahaemolyticus and a nontoxigenic strain V. cholera.

Effects of Boiling Drinking Water on Diarrhea and Pathogen-Specific Infections in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

Globally, approximately 2 billion people lack microbiologically safe drinking water. Boiling is the most prevalent household water treatment method, yet evidence of its health impact is limited. To conduct this systematic review, we searched four online databases with no limitations on language or publication date. Studies were eligible if health outcomes were measured for participants who reported consuming boiled and untreated water. We used reported and calculated odds ratios (ORs) and random-effects meta-analysis to estimate pathogen-specific and pooled effects by organism group and nonspecific diarrhea. Heterogeneity and publication bias were assessed using I2, meta-regression, and funnel plots; study quality was also assessed. Of the 1,998 records identified, 27 met inclusion criteria and reported extractable data. We found evidence of a significant protective effect of boiling for Vibrio cholerae infections (OR = 0.31, 95% confidence interval [CI] = 0.13-0.79, N = 4 studies), Blastocystis (OR = 0.35, 95% CI = 0.17-0.69, N = 3), protozoal infections overall (pooled OR = 0.61, 95% CI = 0.43-0.86, N = 11), viral infections overall (pooled OR = 0.83, 95% CI = 0.7-0.98, N = 4), and nonspecific diarrheal outcomes (OR = 0.58, 95% CI = 0.45-0.77, N = 7). We found no evidence of a protective effect for helminthic infections. Although our study was limited by the use of self-reported boiling and non-experimental designs, the evidence suggests that boiling provides measureable health benefits for pathogens whose transmission routes are primarily water based. Consequently, we believe a randomized controlled trial of boiling adherence and health outcomes is needed.

Long-term impact of changing childhood malnutrition on rotavirus diarrhoea: Two decades of adjusted association with climate and socio-demographic factors from urban Bangladesh

Background

There is strong association between childhood rotavirus, diarrhoea, climate factors and malnutrition. Conversely, a significant nutritional transition (reduced under-nutrition) with a concurrent increasing trend of rotavirus infection in last decade was also observed among under 5 children, especially in developing countries including Bangladesh. Considering the pathophysiology of rotavirus, there might be an interaction of this nutrition transition which plays a pivotal role in increasing rotavirus infection in addition to climate and other man-made factors in urban areas such as Dhaka, Bangladesh.

Methods

Relevant monthly data from 1993–2012 were extracted from the archive of the Diarrhoeal Disease Surveillance System of icddr, b and linked with data collected from the Dhaka station of the Bangladesh Meteorological Department (mean temperature, rainfall, sea level pressure and humidity). Seasonal autoregressive integrated moving average time series models were deployed to determine the association between the monthly proportion of rotavirus infection and underweight, stunting and wasting adjusting for climate, socio-demographic and sanitation factors.

Finding

The proportion of rotavirus cases among all causes diarrhoea increased from 20% in 1993 to 43% in 2012 (Chi squared for trend p = 0.010). In contrast, underweight, stunting and wasting decreased from 59%-29% (p<0.001); 53%-21% (p<0.001) and 32%-22% (p<0.001) respectively over the same period. Mean ambient temperature increased from 25.76°C-26.62°C (p = 0.07); mean rainfall, sea level pressure and mean humidity decreased from 234.92–111.75 mm (p = 0.5), 1008.30–1006.61 mm of hg (p = 0.02) and 76.63%-70.26% (p<0.001), respectively. In the adjusted model, a decrease in monthly proportion of underweight [coef.: -0.189 (95% CI:-0.376, -0.003)] and wasting [-0.265 (-0.455, -0.075)] were significantly and inversely associated with rotavirus infection. However, an inverse but insignificant association was observed for stunting [-0.070 (-0.249, 0.109)].

Interpretation

The reduction of acute childhood malnutrition is significantly associated with increasing rotavirus diarrhoea among under-5 children. Thus mass vaccination in addition to interventions directed at man-made modifiable predictors for prevention and control is warranted.

Hospital-based Surveillance for Rotavirus Gastroenteritis Among Young Children in Bangladesh: Defining the Potential Impact of a Rotavirus Vaccine Program

BACKGROUND

In anticipation of introduction of a rotavirus vaccine into the national immunization program of Bangladesh, active hospital-based surveillance was initiated to provide prevaccine baseline data on rotavirus disease.

METHODS

Children 5 years of age and younger admitted with acute gastroenteritis (AGE) (≥3 watery or looser-than-normal stools or ≥1 episode of forceful vomiting) at 7 hospitals throughout Bangladesh were identified. Clinical information and stool specimens were collected from every 4th patient. Specimens were tested for rotavirus antigen by enzyme immunoassays; 25% of detected rotaviruses were genotyped.

RESULTS

From July 2012 to June 2015, rotavirus was detected in 2432 (64%) of 3783 children hospitalized for AGE. Eight enrolled children died, including 4 (50%) who were rotavirus positive. Rotavirus was detected year-round in Bangladesh with peak detection rates of >80% during November-February. Most (86%) rotavirus AGE cases were 6-23 months of age. Sixty-nine percent of children with rotavirus had severe disease (Vesikari score, ≥11). Among 543 strains genotyped, G1P[8] (31%) and G12P[8] (29%) were the most common.

CONCLUSIONS

Rotavirus is a major cause of morbidity in Bangladeshi children, accounting for nearly two-thirds of AGE hospitalizations. These data highlight the potential value of rotavirus vaccination in Bangladesh, and will be the key for future measurement of vaccine impact.