Peer-reviewed article
Beyond Rotavirus: Persistence of Norovirus, Adenovirus, and Astrovirus in Paediatric Gastroenteritis in the Republic of Congo After Vaccine Introduction.
Mboungou CLD, Mapanguy CCM, Anh DD, Vouvoungui JC, Mouanga AM et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined viral causes of severe diarrhea in young children hospitalized in Brazzaville, Republic of Congo, ten years after rotavirus vaccine introduction. Among 227 children under five, 75% tested positive for at least one of four enteric viruses: rotavirus (58%), norovirus (34%), adenovirus (11%), and astrovirus (7%), with nearly a third experiencing co-infections. Despite rotavirus vaccination, norovirus and other enteric viruses remain major contributors to childhood gastroenteritis, with cases peaking during dry seasons and among infants aged 6-24 months.
Key points
- Rotavirus was detected in 58% of hospitalized children despite vaccine introduction in 2014, but non-rotavirus viruses were also common
- Norovirus (34% detection) and adenovirus (11%) co-circulate with rotavirus, with co-infections occurring in 32% of cases
- Norovirus genotype GII.P31 (82%) and adenovirus type 41 (67%) were predominant
- Gastroenteritis cases peaked during the dry season and were highest in children aged 6-24 months
- From November 2022, cases of gastroenteritis with unknown cause increased, suggesting circulation of pathogens not targeted by current diagnostics
Limitations
This cross-sectional study from one city in Congo cannot establish causality or trends over time, and the 25% of cases testing negative for the four targeted viruses suggests other etiologic agents are not identified. The study does not compare vaccination coverage or outcomes between vaccinated and unvaccinated children.
Abstract
Despite the introduction of rotavirus vaccines, gastroenteritis remains a major cause of paediatric morbidity and mortality in the Republic of Congo. This study investigated the prevalence and genetic diversity of non-rotavirus enteric viruses including norovirus (NoV), adenovirus (AdV), and astrovirus (AstV) ten years after the introduction of the rotavirus vaccine in 2014. A cross-sectional study was conducted between 2022 and 2023 among 227 children (≤ 5 years old) hospitalised for acute gastroenteritis in Brazzaville. Stool samples were analysed by multiplex RT-PCR to detect RVA, NoV, AdV, and AstV. Positive AdV and NoV samples underwent genotyping by PCR and sequencing. The incidence of gastroenteritis peaked during the dry season, with the highest burden observed among children aged 6-24 months. Overall, 75% (n = 170/227) of children tested positive for at least one virus; RVA was detected in 58% (n = 131/227), followed by NoV in 34% (n = 77/227), AdV in 11% (n = 24/227), and AstV in 7% (n = 16/227), while 25% (n = 57/227) tested negative for all four viruses. Co-infections were observed in 32% of children (n = 72/227), most commonly RVA-NoV. The predominant genotype of norovirus was GII.P31 (82%), and that of adenovirus was type 41 (67%). Notably, from November 2022, gastroenteritis of unknown aetiology peaked, coinciding with a decline in the four targeted viruses. NoV, AstV, and AdV continue to contribute to the gastroenteritis burden in Congolese children. The high circulation of NoV and the seasonal surge of unexplained cases highlight the need for broadened molecular surveillance, incorporation of bacterial diagnostics, and consideration of future NoV vaccine strategies.