Epidemiology and molecular characterization of avian influenza A viruses H5N1 and H3N8 subtypes in poultry farms and live bird markets in Bangladesh.

Avian influenza virus (AIV) remains a global threat, with waterfowl serving as the primary reservoir from which viruses spread to other hosts. Highly pathogenic avian influenza (HPAI) H5 viruses continue to be a devastating threat to the poultry industry and an incipient threat to humans. A cross-sectional study was conducted in seven districts of Bangladesh to estimate the prevalence and subtypes (H3, H5, and H9) of AIV in poultry and identify underlying risk factors and phylogenetic analysis of AIVs subtypes H5N1 and H3N8. Cloacal and oropharyngeal swab samples were collected from 500 birds in live bird markets (LBMs) and poultry farms. Each bird was sampled by cloacal and oropharyngeal swabbing, and swabs were pooled for further analysis. Pooled samples were analyzed for the influenza A virus (IAV) matrix (M) gene, followed by H5 and H9 molecular subtyping using real-time reverse transcription-polymerase chain reaction (rRT-PCR). Non-H5 and Non-H9 influenza A virus positive samples were sequenced to identify possible subtypes. Selected H5 positive samples were subjected to hemagglutinin (HA) and neuraminidase (NA) gene sequencing. Multivariable logistic regression was used for risk factor analysis. We found that IAV M gene prevalence was 40.20% (95% CI 35.98-44.57), with 52.38%, 46.96%, and 31.11% detected in chicken, waterfowl, and turkey, respectively. Prevalence of H5, H3, and H9 reached 22%, 3.4%, and 6.9%, respectively. Waterfowl had a higher risk of having AIV (AOR: 4.75), and H5 (AOR: 5.71) compared to chicken; more virus was detected in the winter season than in the summer season (AOR: 4.93); dead birds had a higher risk of AIVs and H5 detection than healthy birds, and the odds of H5 detection increased in LBM. All six H5N1 viruses sequenced were clade 2.3.2.1a-R1 viruses circulating since 2015 in poultry and wild birds in Bangladesh. The 12 H3N8 viruses in our study formed two genetic groups that had more similarity to influenza viruses from wild birds in Mongolia and China than to previous H3N8 viruses from Bangladesh. The findings of this study may be used to modify guidelines on AIV control and prevention to account for the identified risk factors that impact their spread.

The Pregnancy, Arsenic, and Immune Response (PAIR) Study in rural northern Bangladesh.

BACKGROUND: Arsenic exposure and micronutrient deficiencies may alter immune reactivity to influenza vaccination in pregnant women, transplacental transfer of maternal antibodies to the foetus, and maternal and infant acute morbidity. OBJECTIVES: The Pregnancy, Arsenic, and Immune Response (PAIR) Study was designed to assess whether arsenic exposure and micronutrient deficiencies alter maternal and newborn immunity and acute morbidity following maternal seasonal influenza vaccination during pregnancy. POPULATION: The PAIR Study recruited pregnant women across a large rural study area in Gaibandha District, northern Bangladesh, 2018-2019. DESIGN: Prospective, longitudinal pregnancy and birth cohort. METHODS: We conducted home visits to enrol pregnant women in the late first or early second trimester (11-17 weeks of gestational age). Women received a quadrivalent seasonal inactivated influenza vaccine at enrolment. Follow-up included up to 13 visits between enrolment and 3 months postpartum. Arsenic was measured in drinking water and maternal urine. Micronutrient deficiencies were assessed using plasma biomarkers. Vaccine-specific antibody titres were measured in maternal and infant serum. Weekly telephone surveillance ascertained acute morbidity symptoms in women and infants. PRELIMINARY RESULTS: We enrolled 784 pregnant women between October 2018 and March 2019. Of 784 women who enrolled, 736 (93.9%) delivered live births and 551 (70.3%) completed follow-up visits to 3 months postpartum. Arsenic was detected (≥0.02 µg/L) in 99.7% of water specimens collected from participants at enrolment. The medians (interquartile ranges) of water and urinary arsenic at enrolment were 5.1 (0.5, 25.1) µg/L and 33.1 (19.6, 56.5) µg/L, respectively. Water and urinary arsenic were strongly correlated (Spearman's ⍴ = 0.72) among women with water arsenic ≥ median but weakly correlated (⍴ = 0.17) among women with water arsenic < median. CONCLUSIONS: The PAIR Study is well positioned to examine the effects of low-moderate arsenic exposure and micronutrient deficiencies on immune outcomes in women and infants. REGISTRATION: NCT03930017.

Pharmacodynamics of Piperacillin-Tazobactam/Amikacin Combination versus Meropenem against Extended-Spectrum ß-Lactamase-Producing Escherichia coli in a Hollow Fiber Infection Model.

Carbapenems are recommended for the treatment of urosepsis caused by extended-spectrum ß-lactamase (ESBL)-producing, multidrug-resistant Escherichia coli; however, due to selection of carbapenem resistance, there is an increasing interest in alternative treatment regimens including the use of ß-lactam-aminoglycoside combinations. We compared the pharmacodynamic activity of piperacillin-tazobactam and amikacin as mono and combination therapy versus meropenem monotherapy against extended-spectrum ß-lactamase (ESBL)-producing, piperacillin-tazobactam resistant E. coli using a dynamic hollow fiber infection model (HFIM) over 7 days. Broth-microdilution was performed to determine the MIC of E. coli isolates. Whole genome sequencing was conducted. Four E. coli isolates were tested in HFIM with an initial inoculum of ~107 CFU/mL. Dosing regimens tested were piperacillin-tazobactam 4.5 g, 6-hourly, plus amikacin 30 mg/kg, 24-hourly, as combination therapy, and piperacillin-tazobactam 4.5 g, 6-hourly, amikacin 30 mg/kg, 24-hourly, and meropenem 1 g, 8-hourly, each as monotherapy. We observed that piperacillin-tazobactam and amikacin monotherapy demonstrated initial rapid bacterial killing but then led to amplification of resistant subpopulations. The piperacillin-tazobactam/amikacin combination and meropenem experiments both attained a rapid bacterial killing (~4-5 log10) within 24 h and did not result in any emergence of resistant subpopulations. Genome sequencing demonstrated that all ESBL-producing E. coli clinical isolates carried multiple antibiotic resistance genes including blaCTX-M-15, blaOXA-1, blaEC, blaTEM-1, and aac(6')-Ib-cr. These results suggest that the combination of piperacillin-tazobactam/amikacin may have a potential role as a carbapenem-sparing regimen, which should be tested in future urosepsis clinical trials.

Pharmacodynamic evaluation of piperacillin/tazobactam versus meropenem against extended-spectrum ß-lactamase-producing and non-producing Escherichia coli clinical isolates in a hollow-fibre infection model.

BACKGROUND: Urosepsis caused by extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli is increasing worldwide. Carbapenems are commonly recommended for the treatment of ESBL infections; however, to minimize the emergence of carbapenem resistance, interest in alternative treatments has heightened. OBJECTIVES: This study compared pharmacodynamics of piperacillin/tazobactam versus meropenem against ESBL-producing and non-producing E. coli clinical isolates. METHODS: E. coli isolates, obtained from national reference laboratory in Bangladesh, were characterized by phenotypic tests, WGS, susceptibility tests and mutant frequency analysis. Three ESBL-producing and two non-producing E. coli were exposed to piperacillin/tazobactam (4.5 g, every 6 h and every 8 h, 30 min infusion) and meropenem (1 g, every 8 h, 30 min infusion) in a hollow-fibre infection model over 7 days. RESULTS: Piperacillin/tazobactam regimens attained ∼4-5 log10 cfu/mL bacterial killing within 24 h and prevented resistance emergence over the experiment against ESBL-producing and non-producing E. coli. However, compared with 8 hourly meropenem, the 6 hourly piperacillin/tazobactam attained ∼1 log10 lower bacterial kill against one of three ESBL-producing E. coli (CTAP#173) but comparable killing for the other two ESBL-producing (CTAP#168 and CTAP#169) and two non-producing E. coli (CTAP#179 and CTAP#180). The 6 hourly piperacillin/tazobactam regimen attained ∼1 log10 greater bacterial kill compared with the 8 hourly regimen against CTAP#168 and CTAP#179 at 24 h. CONCLUSIONS: Our study suggests piperacillin/tazobactam may be a potential alternative to carbapenems to treat urosepsis caused by ESBL-producing E. coli, although clinical trials with robust design are needed to confirm non-inferiority of outcome.

Pharmacodynamic evaluation of piperacillin/tazobactam against extended-spectrum ß-lactamase (ESBL)-producing versus non-ESBL-producing Escherichia coli in a hollow-fibre infection model.

Extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli are a global public-health concern. We evaluated the pharmacodynamic activity of piperacillin/tazobactam (TZP) dosing regimens against ESBL-producing versus non-ESBL-producing E. coli. Five E. coli clinical isolates were obtained from Bangladesh. Broth microdilution and whole-genome sequencing (WGS) were performed on the five studied isolates. Three TZP-susceptible ESBL-producing and two non-ESBL-producing E. coli were exposed to TZP regimens of 4.5 g every 6 h (q6h) and every 8 h (q8h) as a 30-min infusion in a dynamic hollow-fibre infection model over 7 days. The extent of bacterial killing was ∼4-5 log10 CFU/mL against ESBL-producing and non-ESBL-producing E. coli with TZP q6h and q8h regimens over the first 8 h. Bacterial killing was similar between two of three ESBL-producing (CTAP#168 and CTAP#169) and two non-ESBL-producing (CTAP#179 and CTAP#180) E. coli clinical isolates over the course of the experiment. ESBL-producing CTAP#173 E. coli was poorly killed (∼1 log) compared with two non-ESBL-producing E. coli over 168 h. WGS revealed that ESBL-producing E. coli isolates co-harboured multiple antimicrobial resistance genes such as blaCTX-M-15, blaEC, blaOXA-1, blaTEM-1 and aac(6')-Ib-cr5. Overall, TZP q6h and q8h dosing regimens attained >3 log bacterial kill against all ESBL-producing or non-ESBL-producing E. coli within 24 h and maintained and prevented the emergence of resistance through the end of the experiment. In conclusion, TZP standard regimens resulted in similar bacterial killing and prevented the emergence of resistance against CTX-M-15-type ESBL-producing and non-ESBL-producing E. coli clinical isolates.

Environmental Change and Zoonotic Disease Risk at Human-Macaque Interfaces in Bangladesh.

Anthropogenic land-use changes increase the frequency of interactions and habitat overlap between humans and macaques which play an important role in zoonotic disease transmission. This exploratory qualitative study aimed to examine connections between land-use change and macaque-human interactions and assess the chance of zoonotic disease transmission. We conducted ethnographic interviews and focus group discussions in Old Dhaka, Madaripur, and Chandpur, Bangladesh. Participants reported significant anthropogenic landscape transformations leading to increased human-macaque contact in the study areas. Participants also reported that all three sites underwent substantial landscape alteration from natural or agricultural land to a human-altered environment with roads, commercial, and residential buildings. Participants noted that the disappearance of forestland appeared to increase the macaque dependence on backyard fruit trees. Where rivers and ponds were filled to support local construction, macaques were also observed as becoming more dependent upon human water sources. These changed may help expanding the macaques' foraging areas, and they appear to be invading new areas where people are not culturally habituated to living with them. In response, many residents reported reacting aggressively toward the macaques, which they believed led to more bites and scratches. However, other respondents accepted the presence of macaques around their homes. Few participants considered macaques to be a source of disease transmission. This study revealed that local environmental changes, deforestation, urban expansion, construction, and water bodies' disappearance are linked to increasing human-macaque interactions. Understanding these interactions is critical to develop successful mitigation interventions at interfaces with a high risk for viral disease spillover.

Inference of Nipah virus evolution, 1999-2015.

Despite near-annual human outbreaks of Nipah virus (NiV) disease in Bangladesh, typically due to individual spillover events from the local bat population, only twenty whole-genome NiV sequences exist from humans and ten from bats. NiV whole-genome sequences from annual outbreaks have been challenging to generate, primarily due to the low viral load in human throat swab and serum specimens. Here, we used targeted enrichment with custom NiV-specific probes and generated thirty-five additional unique full-length genomic sequences directly from human specimens and viral isolates. We inferred the temporal and geographic evolutionary history of NiV in Bangladesh and expanded a tool to visualize NiV spatio-temporal spread from a Bayesian continuous diffusion analysis. We observed that strains from Bangladesh segregated into two distinct clades that have intermingled geographically in Bangladesh over time and space. As these clades expanded geographically and temporally, we did not observe evidence for significant branch and site-specific selection, except for a single site in the Henipavirus L polymerase. However, the Bangladesh 1 and 2 clades are differentiated by mutations initially occurring in the polymerase, with additional mutations accumulating in the N, G, F, P, and L genes on external branches. Modeling the historic geographical and temporal spread demonstrates that while widespread, NiV does not exhibit significant genetic variation in Bangladesh. Thus, future public health measures should address whether NiV within in the bat population also exhibits comparable genetic variation, if zoonotic transmission results in a genetic bottleneck and if surveillance techniques are detecting only a subset of NiV.

Hospital-based Surveillance for Pediatric Norovirus Gastroenteritis in Bangladesh, 2012-2016.

BACKGROUND: Globally, noroviruses are recognized as an important cause of acute gastroenteritis (AGE), but data from low and middle-income countries are limited. AIMS: To examine the epidemiology and strain diversity of norovirus infections among children hospitalized for AGE in Bangladesh. METHODS: We implemented active surveillance of children <5 years of age hospitalized with AGE at 8 geographically dispersed tertiary care hospitals in Bangladesh from July 2012 to June 2016. We tested random samples of AGE cases stratified by site and age group for norovirus by real-time RT-PCR. Noro-positive specimens were genotyped. Coinfection with rotavirus was assessed based on prior EIA testing. RESULTS: We enrolled 5622 total AGE cases, of which 1008 were tested for norovirus. Total of 137 (14%) AGE cases tested positive for norovirus (range, 11%-17% by site). Most (94%) norovirus-associated hospitalizations were among children less than 2 years of age. Norovirus was detected year-round, with higher detection from March to June (20%-38%) and November to January (9%-18%). Genogroup II (GII) noroviruses were detected in 96% of cases, and the most frequent genotypes were GII.4 Sydney [P4 New Orleans] (33%), GII.3 [P16] (20%), and GII.4 Sydney [P16] (11%). The proportion of norovirus-positive specimens was significantly greater among rotavirus-negative AGE patients compared with rotavirus-positive AGE patients (27% vs. 5%, P < 0.001). As measured by the Vesikari severity score, a similar proportion of norovirus and rotavirus positive AGE patients were considered severe (68% vs. 70%, P = 0.86). CONCLUSIONS: Norovirus is an important cause of AGE hospitalization in Bangladeshi children with most infections caused by GII viruses.

Investigation of a Large Diphtheria Outbreak and Cocirculation of Corynebacterium pseudodiphtheriticum Among Forcibly Displaced Myanmar Nationals, 2017-2019.

BACKGROUND: Diphtheria, a life-threatening respiratory disease, is caused mainly by toxin-producing strains of Corynebacterium diphtheriae, while nontoxigenic corynebacteria (eg, Corynebacterium pseudodiphtheriticum) rarely causes diphtheria-like illness. Recently, global diphtheria outbreaks have resulted from breakdown of health care infrastructures, particularly in countries experiencing political conflict. This report summarizes a laboratory and epidemiological investigation of a diphtheria outbreak among forcibly displaced Myanmar nationals in Bangladesh. METHODS: Specimens and clinical information were collected from patients presenting at diphtheria treatment centers. Swabs were tested for toxin gene (tox)-bearing C. diphtheriae by real-time polymerase chain reaction (RT-PCR) and culture. The isolation of another Corynebacterium species prompted further laboratory investigation. RESULTS: Among 382 patients, 153 (40%) tested tox positive for C. diphtheriae by RT-PCR; 31 (20%) PCR-positive swabs were culture confirmed. RT-PCR revealed 78% (298/382) of patients tested positive for C. pseudodiphtheriticum. Of patients positive for only C. diphtheriae, 63% (17/27) had severe disease compared to 55% (69/126) positive for both Corynebacterium species, and 38% (66/172) for only C. pseudodiphtheriticum. CONCLUSIONS: We report confirmation of a diphtheria outbreak and identification of a cocirculating Corynebacterium species. The high proportion of C. pseudodiphtheriticum codetection may explain why many suspected patients testing negative for C. diphtheriae presented with diphtheria-like symptoms.

Etiology of Severe Acute Respiratory Infections, Bangladesh, 2017.

In April 2017, surveillance detected a surge in severe acute respiratory infections (SARI) in Bangladesh. We collected specimens from SARI patients and asymptomatic controls for analysis with multipathogen diagnostic tests. Influenza A(H1N1)pdm09 was associated with the SARI epidemic, suggesting that introducing vaccines and empiric antiviral drugs could be beneficial.

Electronic decision support and diarrhoeal disease guideline adherence (mHDM): a cluster randomised controlled trial.

BACKGROUND: Acute diarrhoeal disease management often requires rehydration alone without antibiotics. However, non-indicated antibiotics are frequently ordered and this is an important driver of antimicrobial resistance. The mHealth Diarrhoea Management (mHDM) trial aimed to establish whether electronic decision support improves rehydration and antibiotic guideline adherence in resource-limited settings. METHODS: A cluster randomised controlled trial was done at ten district hospitals in Bangladesh. Inclusion criteria were patients aged 2 months or older with uncomplicated acute diarrhoea. Admission orders were observed without intervention in the pre-intervention period, followed by randomisation to electronic (rehydration calculator) or paper formatted WHO guidelines for the intervention period. The primary outcome was rate of intravenous fluid ordered as a binary variable. Generalised linear mixed-effect models, accounting for hospital clustering, served as the analytical framework; the analysis was intention to treat. The trial is registered with ClinicalTrials.gov (NCT03154229) and is completed. FINDINGS: From March 11 to Sept 10, 2018, 4975 patients (75·6%) of 6577 screened patients were enrolled. The intervention effect for the primary outcome showed no significant differences in rates of intravenous fluids ordered as a function of decision-support type. Intravenous fluid orders decreased by 0·9 percentage points for paper electronic decision support and 4·2 percentage points for electronic decision support, with a 4·2-point difference between decision-support types in the intervention period (paper 98·7% [95% CI 91·8-99·8] vs electronic 94·5% [72·2-99·1]; pinteraction=0·31). Adverse events such as complications and mortality events were uncommon and could not be statistically estimated. INTERPRETATION: Although intravenous fluid orders did not change, electronic decision support was associated with increases in the volume of intravenous fluid ordered and decreases in antibiotics ordered, which are consistent with WHO guidelines. FUNDING: US National Institutes of Health.

Hospital-based surveillance for Japanese encephalitis in Bangladesh, 2007-2016: Implications for introduction of immunization.

BACKGROUND: Japanese encephalitis (JE) virus is recognized as a major cause of encephalitis in Bangladesh. The World Health Organization (WHO) recommends human immunization as the most effective means to control JE. Several WHO-prequalified vaccines are available to prevent JE but no vaccination program has been implemented in Bangladesh. METHODS: We conducted hospital-based surveillance for acute meningitis-encephalitis syndrome (AMES) to describe JE epidemiology and help inform policy decisions about possible immunization strategies for Bangladesh. RESULTS: During 2007-2016, a total of 6543 AMES patients were identified at four tertiary hospitals. Of the 6525 patients tested, 548 (8%) were classified as JE cases. These 548 patients resided in 36 (56%) out of 64 districts of Bangladesh, with the highest proportion of JE cases among AMES patients (12% and 7%) presenting at two hospitals in the northwestern part of the country. The median age of JE cases was 30 years, and 193 (35%) were aged ≤15 years. The majority of JE cases (80%) were identified from July through November. CONCLUSIONS: Surveillance results suggest that JE continues to be an important cause of meningo-encephalitis in Bangladesh. Immunization strategies including JE vaccine introduction into the routine childhood immunization program or mass vaccination in certain age groups or geographic areas need to be examined, taking into consideration the cost-effectiveness ratio of the approach and potential for decreasing disease burden.

An ethnographic exploration of diarrheal disease management in public hospitals in Bangladesh: From problems to solutions.

INTRODUCTION: Diarrheal disease is one of the most common causes of hospital admission globally. The barriers that influence guideline-adherent care at resource limited hospitals are poorly defined, especially during diarrheal disease outbreaks. The objective of this study was to characterize challenges faced in diarrheal disease management in resource-limited hospitals and identify opportunities to improve care. METHODS: The study was conducted during a diarrheal disease outbreak period at ten public district hospitals distributed across Bangladesh. A rapid ethnographic approach included observations and informal interviews with clinicians, staff nurses and patients. In the first phase, observations identified common and unique challenges in diarrheal management at the ten sites. In the second phase, four hospitals were purposively selected for additional ethnographic study. Systematic observations over 420 total hours were collected from patient-clinician interactions (n = 76) and informal interviews (n = 138). Applied thematic analysis identified factors that influenced hospitalbased diarrhea management. RESULTS: Normalization of guideline deviation was observed at all ten sites, including prescription of non-indicated antibiotics and intravenous (IV) fluids. Conflict between 'what should be done' and 'what can be done' was the most common challenge identified. Clinical assessments and patient treatment plans were established at admission in a median of 2 minutes (n = 76), often without a physical examination (57%; n=43/76). Factors that prevented adherence to clinical guidelines included human resource constraints, conflicts of interests, overcrowding, and inadequate hygiene and sanitation in the emergency department and wards. CONCLUSION: This study identified challenges in hospital-based management of diarrheal disease and opportunities to improve care in seemingly change-resilient hospital settings. The results reveal important areas for intervention and policy engagement that may have additive benefit for both hospitals and their patients. These interventions include targeting barriers to clean-water, sanitation and hygiene that prevent clinicians from adopting guidelines out of concern for hospital acquired infections.

Evaluation of potential risk of transmission of avian influenza A viruses at live bird markets in response to unusual crow die-offs in Bangladesh.

In response to unusual crow die-offs from avian influenza A(H5N1) virus infection during January-February 2017 in Dhaka, Bangladesh, a One Health team assessed potential infection risks in live bird markets (LBMs). Evidence of aerosolized avian influenza A viruses was detected in LBMs and in the respiratory tracts of market workers, indicating exposure and potential for infection. This study highlighted the importance of surveillance platforms with a coordinated One Health strategy to investigate and mitigate zoonotic risk.

Infectious Etiologies of Intussusception Among Children <2 Years Old in 4 Asian Countries.

BACKGROUND: The etiology of intussusception, the leading cause of bowel obstruction in infants, is unknown in most cases. Adenovirus has been associated with intussusception and slightly increased risk of intussusception with rotavirus vaccination has been found. We conducted a case-control study among children <2 years old in Bangladesh, Nepal, Pakistan, and Vietnam to evaluate infectious etiologies of intussusception before rotavirus vaccine introduction. METHODS: From 2015 to 2017, we enrolled 1-to-1 matched intussusception cases and hospital controls; 249 pairs were included. Stool specimens were tested for 37 infectious agents using TaqMan Array technology. We used conditional logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) of each pathogen associated with intussusception in a pooled analysis and quantitative subanalyses. RESULTS: Adenovirus (OR, 2.67; 95% CI, 1.75-4.36) and human herpes virus 6 (OR, 3.50; 95% CI, 1.15-10.63) were detected more frequently in cases than controls. Adenovirus C detection <20 quantification cycles was associated with intussusception (OR, 18.59; 95% CI, 2.45-140.89). Wild-type rotavirus was not associated with intussusception (OR, 1.07; 95% CI, 0.52-2.22). CONCLUSIONS: In this comprehensive evaluation, adenovirus and HHV-6 were associated with intussusception. Future research is needed to better understand mechanisms leading to intussusception, particularly after rotavirus vaccination.

Preparing for safety monitoring after rotavirus vaccine introduction - Assessment of baseline epidemiology of intussusception among children <2 years of age in four Asian countries.

Intussusception is the invagination of one segment of the bowel into a distal segment, characterized by symptoms of bloody stool, vomiting, and abdominal pain. Previous studies have found regional differences in incidence but the etiology of most intussusception cases is unknown. Rotavirus vaccines were associated with a slightly of increased risk of intussusception in post-licensure evaluations in high- and middle-income countries, but not in low income African countries. To describe the baseline epidemiology of intussusception in young children prior to rotavirus vaccine implementation, active sentinel hospital surveillance for intussusception in children < 2 years of age was conducted in 4 low income Asian countries (Bangladesh, Nepal, Pakistan and Vietnam). Over a 24-month period, 15 sites enrolled 1,415 intussusception cases, of which 70% were enrolled in Vietnam. Overall, 61% of cases were male and 1% (n = 16) died, ranging from 8% in Pakistan to 0% in Vietnam. The median age of cases enrolled ranged from 6 months in Bangladesh and Pakistan to 12 months in Vietnam. The proportion of cases receiving surgical management was 100% in Bangladesh, 88% in Pakistan, 61% in Nepal, and 1% in Vietnam. The high proportion of males and median age of cases around 6 months of age found in this regional surveillance network are consistent with previous descriptions of the epidemiology of intussusception in these countries and elsewhere. Differences in management and the fatality rate of cases between the countries likely reflect differences in access to healthcare and availability of diagnostic modalities. These baseline data will be useful for post-rotavirus vaccine introduction safety monitoring.

Molecular xenomonitoring for Wuchereria bancrofti in Culex quinquefasciatus in two districts in Bangladesh supports transmission assessment survey findings.

BACKGROUND: Careful monitoring for recrudescence of Wuchereria bancrofti infection is necessary in communities where mass drug administration (MDA) for the elimination of lymphatic filariasis (LF) as a public health problem has been stopped. During the post-MDA period, transmission assessment surveys (TAS) are recommended by the World Health Organization to monitor the presence of the parasite in humans. Molecular xenomonitoring (MX), a method by which parasite infection in the mosquito population is monitored, has also been proposed as a sensitive method to determine whether the parasite is still present in the human population. The aim of this study was to conduct an MX evaluation in two areas of Bangladesh, one previously endemic district that had stopped MDA (Panchagarh), and part of a non-endemic district (Gaibandha) that borders the district where transmission was most recently recorded. METHODOLOGY/PRINCIPAL FINDINGS: Mosquitoes were systematically collected from 180 trap sites per district and mosquito pools were tested for W. bancrofti using real-time PCR. A total of 23,436 intact mosquitoes, representing 31 species, were collected from the two districts, of which 10,344 (41%) were Culex quinquefasciatus, the vector of W. bancrofti in Bangladesh. All of the 594 pools of Cx. quinquefasciatus tested by real-time PCR were negative for the presence of W. bancrofti DNA. CONCLUSIONS/SIGNIFICANCE: This study suggested the absence of W. bancrofti in these districts. MX could be a sensitive tool to confirm interruption of LF transmission in areas considered at higher risk of recrudescence, particularly in countries like Bangladesh where entomological and laboratory capacity to perform MX is available.

An update from hospital-based surveillance for rotavirus gastroenteritis among young children in Bangladesh, July 2012 to June 2017.

INTRODUCTION: In preparation for the introduction of a rotavirus vaccine into the routine immunization program of Bangladesh in 2018, we report data and highlight evolving genotypes from five years of active hospital-based rotavirus surveillance which began in July 2012. METHODS: We enrolled and collected fresh stool from every fourth child < 5 years admitted with acute gastroenteritis (AGE) at 8 participating surveillance hospitals. Rotavirus infections were detected by enzyme immune assay. Twenty-five percent of rotavirus isolates were genotyped using reverse transcription polymerase chain reaction. RESULTS: We found that 64% (4832/7562) of children < 5 years of age admitted with AGE had evidence of rotavirus infection. The majority (57%) of patients with rotavirus infection were <12 months of age. The most common strains were G1P[8] (43%), G12P[8] (15%) and G9P[8] (9%); 11% of children had mixed infection.G3P[8], which has not been reported in Bangladesh since 2001, was documented for the first time in our surveillance system. CONCLUSIONS: The high burden of rotavirus-associated hospitalizations highlights the potential value of rotavirus vaccination in Bangladesh. Continued surveillance is important for monitoring the impact of vaccination as well as monitoring evolving genotypes.

Epidemiology of childhood intussusception in Bangladesh: Findings from an active national hospital based surveillance system, 2012-2016.

INTRODUCTION: Rotavirus vaccines have significantly decreased the burden of diarrheal diseases in countries that have introduced them into their immunization programs. In some studies, there has been a small association between rotavirus vaccines and intussusception in post-marketing surveillance, highlighting the importance of tracking incidence before and after vaccine introduction. The objective of this study was to describe the epidemiology of intussusception among Bangladeshi children pre-vaccine introduction. METHODS: We conducted active, hospital-based surveillance for intussusception at 7 tertiary care hospitals with pediatric surgical facilities during July 2012 to September 2016. Hospitalized children under 2years of age were identified according to Brighton Collaboration level 1 criteria for intussusception. The frequency and proportion of intussusception among overall surgical admissions, as well as the demographic and clinical information of the cases is described. RESULTS: Overall 153 cases of intussusception among children <2years-old were identified at participating sites over the enrolment period, confirmed by Level 1 Brighton criteria. These cases represented 2% of all surgical admissions under 2years of age. One hundred twelve cases (73%) were male; the median age was 7months; and the median duration of hospitalization was 7days. One hundred forty-six (95%) children with intussusception required surgery, and 11 (7%) died. CONCLUSIONS: Confirmed cases of intussusception represented nearly 2% of pediatric surgical admissions at tertiary referral centers in Bangladesh during the study period and 7% of children with intussusception died. Given the high burden of rotavirus disease in Bangladesh, vaccine introduction is warranted, however, further studies after introduction of rotavirus vaccine are necessary to determine any association between vaccine and intussusception in this setting.