Characterization of rotavirus infection in children with acute gastroenteritis in Bengo province, Northwestern Angola, prior to vaccine introduction

Abstract

BackgroundRotavirus group A (RVA) is considered the leading cause of pediatric diarrhea, responsible for the high burden of diarrheal diseases in sub-Saharan Africa. Despite recent studies, the existent data are scarce for some African countries like Angola, a country with one of the highest RVA-related death estimates. The aim of this study was to determine the RVA detection rate and circulating genotypes in children less than five years of age with acute gastroenteritis attended at the Bengo General Hospital in Caxito, Bengo province, Angola, before vaccine introduction.MethodsBetween September 2012 and December 2013, 342 fecal specimens were collected from children enrolled. Positive samples for RVA by immunochromatographic rapid test were G and P-typed by hemi-nested type-specific multiplex PCR, and subgrouped for the VP6 gene. VP4 and VP7 genes from a subset of samples were sequenced for phylogenetic analysis.ResultsDuring the study period, a high RVA detection rate was registered (25.1%, 86/342).The age group most affected by RVA infection includes children under 6 months of age (p<0.01). Vomiting was highly associated with RVA infection (72.1%; p<0.001).From the 86 RVA-positive samples, 72 (83.7%) were genotyped. The most prevalent genotype was G1P[8] (34/72; 47.2%), followed by the uncommon G1P[6] (21/72; 29.2%), and G2P[4] (9/72; 12.5%). Only two G-types were found: G1 (60/72; 83.3%) and G2 (11/72; 15.3%). Among the P-genotypes, P[8] was the most prevalent (34/72; 47.2%), followed by P[6] (22/72; 30.6%) and P[4] (9/72; 12.5%). In the phylogenetic trees, the identified G and P-types clustered tightly together and with reference sequences in specific monophyletic groups, with highly significant bootstrap values (≥92%).ConclusionThis pre-vaccination study revealed, for the first time for Bengo province (Angola), the RVA genotype profile, including phylogenetic relationships, and a high RVA detection rate, supporting the immediate introduction of a RVA vaccine in the national immunization programme.

Epidemiology of enteric viruses in children with gastroenteritis in Ogun State, Nigeria

“…Comparing the EVs, the age distribution of patients with viral gastroenteritis was not statistically significant, but they were detected mainly in children 0 to 24 months, which is in agreement with reports from Nigeria . Consistent with the findings from Angola, Gabon, and Nigeria, the burden of viral gastroenteritis in this study is predominantly in males, although there was no significant association. No causal relationship was established between viral gastroenteritis and sociodemographic/risk factors.…”

“…Worldwide, RVA is responsible for many deaths, mainly among young children in Asia and Africa . RVA was detected in 16.6% cases, which is lower to studies from Angola, Burkina Faso, Northern Italy, Enugu, and Edo States, Nigeria . Both NoV and HAdV in this study were found in 5.1% of children with gastroenteritis which is similar to that reported in Republic Democratic of Congo and North East, Nigeria but lower compared with studies in Albania, Burkina Faso, Northern Italy, and Ondo State, Nigeria .…”

Rotavirus: Genetics, pathogenesis and vaccine advances

“…Rotavirus gastroenteritis causes severe diarrhea in infants and young children in the whole world, particularly in the remote areas where there is poor health facilities and lack of domestic sanitation conditions. 50 The adults are rarely infected with RV. As a single infection will enhance the immunocompetence and will lower the chance of future infection in an individual.…”

Variability in the genotypes of rotavirus detected in Cte dIvoire from 2010-2016

“…Group A rotaviruses are the major viral agent of acute gastroenteritis and severe diarrhea in children <5 years old (Gasparinho et al, 2017). Globally, this virus is responsible for about 40% of cases of severe diarrhea with hospitalization and 5% of deaths in children under five years (Eteme et al, 2015).…”

“…The two vaccines have been proven to be effective worldwide, but lower efficacy was observed in low-income countries from Africa and Southern Asia. Among the several hypotheses used to explain the differences in the immune response and consequent efficacy of these vaccines in low-versus high-income countries, RVA strains diversity, host genetic factors, malnutrition, host co-infection, deficient micronutrient ingestion, and interfering gut flora have been put forward (Gasparinho et al, 2017). Studies conducted in Côte d'Ivoire prior to the sentinel surveillance which started in 2010 showed a predominance of G1 followed by G2.…”