First Molecular Detection and Vp7 (g) Genotyping of Group a Rotavirus by Semi-nested Rt-pcr from Sewage in Nigeria

Rotavirus is the leading cause of viral gastroenteritis worldwide, and sewage is a major source of the virus dissemination in the environment. Our aim was to detect and genotype rotaviruses from sewages in Nigeria. One hundred and ninety sewage samples were collected between June 2014 and January 2015. The two phase concentration method using PEG 6000 and dextran was used to concentrate sewage samples following WHO protocols. Molecular detection was performed by RT-PCR, and VP7 genotyping by semi-nested multiplex PCR. A total of 14.2% (n = 27) samples tested positive. Monthly distribution showed that June to September had a lower rate (3.7% to 7.4%), while October to January recorded 11% to 26%. Genotype G1 predominated followed by G8, G9, G4 and lastly G2, 7.4% (n = 2) of isolates were nontypeable. This is the first report of rotavirus detection in sewages from Nigeria. Genotype G1 remains the most prevalent genotype. This observation calls for an effort by the governmental authorities to implement a molecular surveillance, both clinical and environmental, in order to provide vital information for the control and the vaccine efficacy not only in Nigeria, but globally.