Human Norovirus prevalence in Africa: a review of studies from 1990 to 2013

Abstract

Abstractobjectives To assess the contribution of Human Norovirus to diarrhoeal diseases in Africa. methods We conducted a systematic review of the PubMed and EMBASE databases for published articles of Human Norovirus in Africa between 1990 and 2013. Data were extracted from selected studies and analysed.results A total of 208 eligible studies were identified, of which 55 (from 19 countries) met the inclusion criteria. Many cases were of sporadic gastroenteritis (70.9%) in children (82%), 65.4% of which were seen in an outpatient setting. Over half (59.4%) of the affected children were under 5 years of age. The pooled prevalence rate of Human NoV was 11% (95% CI 8-14%), and the meta-analysis indicated significant heterogeneity between the studies. However, the conditional negative binomial regression could not clearly find the factors affecting the Human NoV prevalence rates reported. A close relationship was found between Human Norovirus strains from environmental and clinical samples.

Molecular epidemiology of noroviruses in children under 5 years of age with acute gastroenteritis in Yaoundé, Cameroon

“…Globally, 70% of norovirus cases occurred among children 6‐23 months of age, a similar proportion (68%) of norovirus‐associated stools were from children in this age category in our study. The proportion of positive stools (29%) which came from younger infants (0‐5 months of age) was in range with those reported in South Africa and Angola . Similar to reports from other Sub‐Saharan African countries, a substantial proportion of norovirus‐positive stools (83%) were from children below 12 months old in Cameroon …”

“…We detected norovirus in 8.4% of diarrheal stools from hospitalized children under five years of age with sporadic cases of AGE collected from January 2010 to December 2013 in Cameroon. These rates are in the same range as those reported in systematic reviews of noroviruses in Africa with 11% (95% CI, 8%‐14%) prevalence reported across the entire African continent and 12.6% (range 4.6%‐32.4%) in Sub‐Saharan Africa (both symptomatic and asymptomatic cases) between 1990‐2013 . A mean overall prevalence of 13.5% (range 0.8%‐25.5%) was reported among children with AGE (most associated with hospitalization or outpatient treatment) in longitudinal studies conducted from 1976‐1979 and 1997‐2013 .…”

Prevalence and molecular characterization of human noroviruses and sapoviruses in Ethiopia

“…The role of NoVs and SaVs as causative agents of gastroenteritis and their diversity in Africa is not well studied, except in some reports from a few African countries [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. There has been only one published study from Ethiopia regarding the presence and genetic diversity of NoVs [37], and none for SaVs to date.…”

Norovirus prevalence and estimated viral load in symptomatic and asymptomatic children from rural communities of Vhembe district, South Africa

“…Nevertheless most of the NoV studies in Africa have been carried out in urban settings, likely due to the lack of laboratory capacity for Human NoV detection in rural settings [18]. In South Africa, little has been reported on the prevalence and circulating NoV genotypes across the country [18], [19], [20].…”