Abstract

Noroviruses are the primary cause of foodborne infections associated with fresh products. The aim of the present study was to assess agricultural practices and the presence of noroviruses in fruits and vegetables, manure, and irrigation wastewater sampled from the urban and peri-urban irrigated plots of Ouagadougou. A face-to-face survey was conducted using a questionnaire on market garden production practices. A total of 259 samples were collected, including 30 lettuces, 33 tomatoes, 32 carrots, 30 strawberries, 64 manure samples, and 70 irrigation water samples. Reverse transcription (RT)-nested polymerase chain reaction (PCR) was performed with specific primers to detect norovirus genogroups I and II. Overall, the prevalence of noroviruses was 15.9% (31/195) [95% CI, 10.8 to 21.0%] in the irrigation water samples and fresh produce analyzed. No noroviruses were detected in the manure samples. Norovirus genogroup I was detected in 6.7% (2/33) of the tomatoes, 13.3% (4/30) of the lettuces, and 5.7% (4/70) of the irrigation water tested, while norovirus genogroup II was detected in 12.5% (4/32) of the carrots, 36.6% (11/30) of the strawberries, and 8.6% (6/70) of the irrigation water tested. The survey results showed that irrigation water came from untreated sources (dams, wells, canals), and 52% of the farms used untreated manure. Furthermore, no farms implemented measures to limit access by domestic and wild animals.

Key words: Norovirus genogroup I (GI), genogroup II (GII), raw vegetables, wastewater, manure, reverse transcription-polymerase chain reaction (RT?PCR).