Abstract:
Respiratory tract infections are the most frequent presenting complaint accounting for up
to 60% of children with acute febrile illnesses (AFI) seeking health care in Tanzania. The
emergence of COVID-19 has increased the threats of respiratory viruses causing the rise
of incident cases of upper respiratory tract infections (URTI) to 42.82% of cases from all
the diseases and injuries in 2020. Human adenoviruses account for about 2% to 5% of all
respiratory infections worldwide and are a common cause of respiratory tract infections in
children, accounting for 5% to 10% of all lower respiratory tract infections in children.
Viral etiologies of febrile illness cause major disease burden in tropical and subtropical
countries. Despite the burden of acute respiratory infection on morbidity and mortality in
children under the age of five in the world, there is a scarcity of data to evaluate the
contribution and the epidemiological features of viral etiologies of acute febrile illnesses
in Tanzania. The objective of this study was to determine the prevalence and genetic
characteristics of human adenovirus (HAdV) circulating in Kasulu District, Kigoma,
Tanzania. A total of 110 nasopharyngeal swabs were collected from under-five children
with acute febrile illnesses from three health facilities. The collected samples were tested
for HAdV using nested polymerase chain reaction (nPCR). Of the 110 patients, 6 patients
were HAdV-positive and the detection rate was 5.45%. The prevalence of HAdV
infection was higher among females 7.41% (4/56) than males 3.57% (2/54). The analysis
of the nucleotide sequences showed that all six positive samples belonged to HAdV C
type 2 (HAdV C2). Phylogenetic analysis showed that all nucleotide sequences from this
study clustered with HAdV C2 strains from Germany (MH121114.1 and EU867472.1),
China (MH322262.1), Kuwait (MF085403.1 and MF085391.1) and Argentina
(JX173079.1). The findings from this study suggest that active HAdV type 2 circulate
among children in Kasulu district in Tanzania. The results confirm the presence of HAdV among under-five children with acute febrile illnesses. Further studies are required to
investigate the molecular epidemiology of HAdV in the country for appropriate control of
the HAdV-associated diseases in the region.
