Abstract:
Norovirus (NoV) is recognised as a leading cause of gastroenteritis worldwide across all
age groups. The prevalence and diversity of NoVs in many African countries is still
unknown, although early sero-prevalence studies indicated widespread early infection.
Reports on NoVs in Africa vary widely in terms of study duration, population groups and
size, inclusion of asymptomatic controls, as well as genotyping information. This review provides
an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion
criteria for the review were study duration of at least 6 months, population size of >50
and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not
always performed, this was not considered as an inclusion criteria. A literature search containing
the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out
of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the
inclusion criteria, based on sample size or short duration, were included as discussion
points. The majority of studies published focused on children, under five years of age, hospitalised
with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8–
25.5%) in children with gastroenteritis and 9.7% (range 7–31%) in asymptomatic controls,
where tested. NoV GII.4 was the predominant genotype identified in most of the studies that
presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6.
In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable
carriage in asymptomatic children. There is however, a paucity of data on NoV infection
in adults.
