Systematic review of the effect of additional doses of oral rotavirus vaccine on immunogenicity and reduction in diarrhoeal disease among young children

Rotavirus and adenovirus infections in children with acute gastroenteritis after introducing the Rotasiil® vaccine in Kisangani, Democratic Republic of the Congo

BACKGROUND

Although rotavirus vaccination has reduced the global burden of the virus, morbidity and mortality from rotavirus infection remain high in Sub-Saharan Africa. This study aimed to determine the prevalence of rotavirus and adenovirus infections in children under five years with acute gastroenteritis and to identify factors associated with rotavirus infection after the introduction of the Rotasiil® vaccine in 2019 in Kisangani, Democratic Republic of the Congo (DRC).

METHODS

This study consisted of a cross-sectional hospital-based survey conducted from May 2022 to April 2023 in four health facilities in Kisangani, using a fecal-based test (rapid antigenic immuno-chromatographic diagnostic test, BYOSYNEX adenovirus/rotavirus BSS, Biosynex SA, Illkirch-Graffenstaden, France) of rotavirus and adenovirus infections among children under five years of age with acute gastroenteritis.

RESULTS

A total of 320 children under five years of age with acute gastroenteritis were included. The prevalence of rotavirus infection was 34.4%, that of adenovirus was 6.3%, and that of both rotavirus and adenovirus coinfection was 1.3%. The prevalence of rotavirus was significantly higher in unvaccinated children than in vaccinated children (55.4% versus 23.1%; P < 0.001). This difference was observed only in children who received all three vaccine doses. Multivariate logistic regression analysis shows that the rate of rotavirus infection was significantly reduced in vaccinated children (adjusted OR: 0.31 [95% confidence intervals (CI): 0.19-0.56]; P < 0.001) and those whose mothers had an average (adjusted OR: 0.51 [95% CI: 0.25-0.91]; P = 0.018) or high level (adjusted OR: 0.34 [95% CI: 0.20-0.64]; P < 0.001) of knowledge about the rotavirus vaccine.

CONCLUSIONS

The prevalence of rotavirus infection remains high in Kisangani despite vaccination. However, the prevalence of adenovirus infections was low in our series. Complete vaccination with three doses and mothers' average and high level of knowledge about the rotavirus vaccine significantly reduces the rate of rotavirus infection. It is, therefore, essential to strengthen the mothers' health education, continue with the Rotasiil® vaccine, and ensure epidemiological surveillance of rotavirus infection.

Nonsecretor Phenotype Is Associated With Less Risk of Rotavirus-Associated Acute Gastroenteritis in a Vaccinated Nicaraguan Birth Cohort

BACKGROUND

Histo-blood group antigens (HBGAs) have been associated with rotavirus vaccine take; but the effect of these HBGAs on rotavirus incidence and risk remains poorly explored in vaccinated populations.

METHODS

Rotavirus-associated acute gastroenteritis (AGE) was assessed in 444 Nicaraguan children followed from birth until 3 years of age. AGE episodes were tested for rotavirus by reverse-transcription quantitative polymerase chain reaction, and saliva or blood was used to determine HBGA phenotypes. Cox proportional hazards models were used to estimate the relative hazard of rotavirus AGE by HBGA phenotypes.

RESULTS

Rotavirus was detected in 109 (7%) stool samples from 1689 AGE episodes over 36 months of observation between June 2017 and July 2021. Forty-six samples were successfully genotyped. Of these, 15 (35%) were rotavirus vaccine strain G1P[8], followed by G8P[8] or G8P[nt] (11 [24%]) and equine-like G3P[8] (11 [24%]). The overall incidence of rotavirus-associated AGE was 9.2 per 100 child-years, and was significantly higher in secretor than nonsecretor children (9.8 vs 3.5/100 child-years, P = .002).

CONCLUSIONS

The nonsecretor phenotype was associated with decreased risk of clinical rotavirus vaccine failure in a vaccinated Nicaraguan birth cohort. These results show the importance of secretor status on rotavirus risk, even in vaccinated children.

Estimating the global impact of rotavirus vaccines on child mortality

OBJECTIVES

We estimated the global impact of rotavirus vaccines on deaths among children under five years old by year.

METHODS

We used a proportionate outcomes model with a finely disaggregated age structure to estimate rotavirus deaths prevented by vaccination over the period 2006-2019 in 186 countries. We ran deterministic and probabilistic uncertainty analyses and compared our estimates to surveillance-based estimates in 20 countries.

RESULTS

We estimate that rotavirus vaccines prevented 139,000 under-five rotavirus deaths (95% uncertainty interval 98,000-201,000) in the period 2006-2019. In 2019 alone, rotavirus vaccines prevented 15% (95% uncertainty interval 11-21%) of under-five rotavirus deaths (0.5% of child mortality). Assuming global use of rotavirus vaccines and coverage equivalent to other co-administered vaccines could prevent 37% of under-five rotavirus deaths (1.2% of child mortality). Our estimates were sensitive to the choice of rotavirus mortality burden data and several vaccine impact modeling assumptions. The World Health Organization's recommendation to remove age restrictions in 2012 could have prevented up to 17,000 rotavirus deaths in the period 2013-2019. Our modeled estimates of rotavirus vaccine impact were broadly consistent with estimates from post-vaccination surveillance sites.

CONCLUSION

Rotavirus vaccines have made a valuable contribution to global public health. Enhanced rotavirus mortality prevention strategies are needed in countries with high mortality in under-5-year-old children.

Potential impact of rotavirus vaccination on reduction of childhood diarrheal disease in India: An analysis of National Family Health Survey-5

Rotavirus is one of the leading causes of diarrhea in infants and young children worldwide. In this study, we investigated the impact of rotavirus vaccination on the prevalence of diarrheal disease among children under five years of age in India. Research on the impact of the rotavirus vaccine on reducing diarrheal disease is therefore important in contributing to the growing body of evidence on the effectiveness of this intervention in improving child health outcomes. We adopted multivariate logistic regression and propensity score matching analysis to examine the association between diarrhea and the rotavirus vaccine. The bivariate analysis finding shows that the prevalence of diarrhea was remarkably higher (9.1%) among children who had not received rotavirus and the prevalence was 7.5%, 7.5%, and 7.2% among children who received one dose, two doses, and three rotavirus doses (all) respectively. The result of multivariate logistic regression shows that children who received all three doses of the rotavirus vaccine were 16% less likely to experience diarrhea compared to those who did not receive any rotavirus vaccine. Our analysis also found that the prevalence of diarrhea decreased significantly in the years following the introduction of the vaccine. The results of this study suggest that the rotavirus vaccine has a significant impact on reducing childhood diarrheal disease in India. These results have the potential to inform policy decisions and enable healthcare professionals to concert their efforts in reducing the diarrheal disease burden and its timely prevention in children. The study will also contribute to the existing literature on the impact of rotavirus vaccination in reducing the prevalence of diarrhea among children in India.