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Safe and effective rotavirus vaccines (RVs) are needed to reduce the enormous public health burden of rotavirus illness in developing countries. Vaccination is critical for effective control of rotavirus infection since it cannot be prevented with improvements in water and sanitation. The International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) has completed several groundbreaking RV trials (Phase I-Phase IV). The safety, immunogenicity, efficacy, and effectiveness of different RVs were evaluated among both urban and rural populations. In this study, we present the results, policy implications, and lessons learned for successful implementation of these trials as well as future directions for rotavirus vaccination in Bangladesh. [ABSTRACT FROM AUTHOR]

Background Following the conclusion of a human rotavirus vaccine (HRV) cluster-randomized, controlled trial (CRT) in Matlab, Bangladesh, HRV was included in Matlab's routine immunization program. We describe the population-level impact of programmatic rotavirus vaccination in Bangladesh in children <2 years of age. Methods Interrupted time series were used to estimate the impact of HRV introduction. We used diarrheal surveillance collected between 2000 and 2014 within the 2 service delivery areas (International Centre for Diarrhoeal Disease Research, Bangladesh [icddr,b] service area [ISA] and government service area [GSA]) of the Matlab Health and Demographic Surveillance System, administered by icddr,b. Age group–specific incidence rates were calculated for both rotavirus-positive (RV+) and rotavirus-negative (RV–) diarrhea diagnoses of any severity presenting to the hospital. We used 2 models to assess the impact within each service area: Model 1 used the pre-vaccine time period in all villages (HRV– and control-only) and Model 2 combined the pre-vaccine time period and the CRT time period, using outcomes from control-only villages. Results Both models demonstrated a downward trend in RV+ diarrheal incidences in the ISA villages during 3.5 years of routine HRV use, though only Model 2 was statistically significant. Significant impacts of HRV on RV+ diarrhea incidences in GSA villages were not observed in either model. Differences in population-level impacts between the 2 delivery areas may be due to the varied rotavirus vaccine coverage and presentation rates to the hospital. Conclusions This study provides initial evidence of the population-level impact of rotavirus vaccines in children <2 years of age in Matlab, Bangladesh. Further studies are needed of the rotavirus vaccine impact after the nationwide introduction in Bangladesh. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the relationship between helminthic infection and allergic diseases. Rabbits with nematode ascaris lumbricoides (Al) antigens were immunized to determine the cross-reactivity of anti-ascaris and antibody elements. Results shows that immunization of rabbits with ascaris antigens from human parasite Al induced the production of antibodies cross-reactivity to house dust mite (HDM) antigens.

Background. Rotavirus is the leading cause of diarrhea-related morbidity and mortality in developing countries, including Bangladesh. The licensed vaccine Rotashield was withdrawn from the market because of an increased risk of intussusception. This study was undertaken to estimate the background incidence rates of intussusception among children aged <2 years, using retrospective and prospective studies in a rural demographic surveillance area in Bangladesh. Methods. All hospital charts of children aged <2 years who presented to the Matlab Hospital and 2 other treatment centers of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), during January 2001-August 2004 were reviewed retrospectively. A prospective surveillance was performed from August 2004 through December 2006 at the 3 treatment centers of ICDDR,B serving Matlab, 4 district and subdistrict government hospitals, and 3 district-based private clinics, to determine population-based rates of intussusception with use of Brighton Collaboration case definitions. All suspected cases of intussusception were referred to the Matlab Hospital by community health research workers for further assessment by a trained medical officer, including performance of an ultrasound examination. Results. In total, 2856 charts of children aged <2 years were reviewed retrospectively, and 4 probable cases and 19 possible cases of intussusception were identified. In the prospective surveillance, of 1508 potential cases, including 41 referred by community health research workers, only 2 cases met the case definition of probable intussusception, and 1 case met the definition of possible intussusception. A total of 123 patients had ultrasound examinations performed. The population-based rates of probable and possible cases of intussusception among children aged <2 years were 0-17.8 and 17.7-81.7 cases per 100,000 children per year, respectively. In the retrospective and prospective surveillance, the rates were 0-18.7 and 0-97 cases per 100,000 children per year, respectively. Conclusions. The incidence of intussusception was low among children in Bangladesh. A surveillance system for intussusception has been fully established in the Matlab surveillance area to diagnose, treat, and refer potential cases. This study provides useful information for detection of intussusception during future studies of newgeneration rotavirus vaccines and also provides background incidence rates for comparison when rotavirus vaccines are introduced. [ABSTRACT FROM AUTHOR]

How Vibrio cholerae spreads around the world and what determines its seasonal peaks in endemic areas are not known. These features of cholera have been hypothesized to be primarily the result of environmental factors associated with aquatic habitats that can now be identified. Since 1997, fortnightly surveillance in 4 widely separated geographic locations in Bangladesh has been performed to identify patients with cholera and to collect environmental data. A total of 5670 patients (53% <5 years of age) have been studied; 14.3% had cholera (10.4% due to V. cholerae O1 El Tor, 3.8% due to O139). Both serogroups were found in all locations; outbreaks were seasonal and often occurred simultaneously. Water-use patterns showed that bathing and washing clothes in tube-well water was significantly protective in two of the sites. These data will be correlated with environmental factors, to develop a model for prediction of cholera outbreaks. [ABSTRACT FROM AUTHOR]

Baqui A H (Community Health Division, International Center for Diarrhoeal Disease Research, Bangladesh) (ICDDR, B) GPO Box 128, Dhaka-1000, Bangladesh), Black R E, Yunus Md, Hoque A R A, Chowhury H R and Sack R B. Methodological issues in diarrhoeal diseases epidemiology: definition of diarrhoeal episodes. 1991; : 1057–1063. A review of the diarrhoeal disease literature reveals considerable variability in the definition of diarrhoeal episodes. The use of various definitions of diarrhoea and episodes leads to misclassification, affects the estimates of the disease burden in communities and reduces comparability of the findings from different studies. This study is an attempt to validate the definition of diarrhoeal episodes using prospectivery collected community-based surveillance data. In comparative validation analyses, three or more loose stools or any number of loose stools containing blood in a 24–hour period seemed to be the best definition of diarrhoea. Three intervening diarrhoea-free days seemed to be the optimum to define a new episode. The implications of using differing definitions and the importance of using a validated definition are discussed. [ABSTRACT FROM PUBLISHER]

Clemens J D (International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh), Stanton B F, Harris J R, Chakraborty J, Sack D A, Rao M R, Ahmed F, Ansaruzzaman M, Yunus M, Svennerholm A M and Holmgren J. Exclusion of clinically atypical or microbiologically mixed diarrhoeal episodes from outcome events in a field trial of oral cholera vaccines. 1989, : 441–445. We investigated whether alternative clinical and microbiological criteria for outcome events affected estimates of vaccine efficacy in a randomized, double-blind field trial of B subunit-killed whole cell (BS-WC) and killed whole cell-only (WC) oral cholera vaccines among 62285 rural Bangladeshi participants. At one year of follow-up estimates of vaccine protective efficacy (PE = 60%, P<0.0001 for BS-WC; PE = 54%, P<0.0001 for WC) against all treated diarrhoeal episodes associated with 01 were similar to estimates of efficacy against only those episodes which were clinically typical and unassociated with additional enteric pathogens (PE = 62%, P<0.0001 for BS-WC; PE = 52%, P<0.0001 for WC). In contrast, estimates of vaccine cross-protection against episodes associated with each of several agents antigenically related to 01 (LT-ETEC, non-cholera sp, sp) were substantially reduced when mixed infections with 01 were excluded. We conclude that restrictive criteria intended to improve the specificity of the definition of cholera did not increase the detectability of vaccine efficacy against 01, but that exclusion of mixed infections with 01 was necessary to avoid false-positive conclusions about vaccine cross-protection against other potential target pathogens. [ABSTRACT FROM PUBLISHER]