Prevalence and associated factors of human caliciviruses infection among patients with gastroenteritis in the Amhara National Regional State, Ethiopia

Abstract Background: Human caliciviruses are the leading cause of gastroenteritis among all age groups worldwide, with an increased burden in developing countries. As there is no surveillance, epidemiological data is limited in Ethiopia. Hence, this study aimed to investigate the prevalence and associated factors of human caliciviruses among patients with gastroenteritis in the Amhara National Regional State, Ethiopia. Methods: Prospective cross-sectional study was conducted from May 2021 to November 2021. A total of 550 study participants with symptoms of gastroenteritis were proportionately assigned to the four study areas. Convenient sampling was used to select the health facilities while study participants were systematically sampled. A fecal sample was collected and analyzed with a one-step real-time RT-PCR. Sociodemographic and other variables were gathered using a pre-tested questionnaire and analyzed by SPSS version 23. A descriptive analysis was performed. Logistic Regressions with adjusted odds ratio (AOR) at the 95%CI were used to assess factors associated with NoV infection. Results: 519 out of 550 samples were analyzed (94.4% response rate). The overall prevalence of norovirus (NoV) was 8.9% (46/519). The positivity rates were higher among the elderly (33.3%) and under-5 children (12.5%). Both genogroup I and genogroup II (GII) were identified, with GII being the predominant, 82.6% (38/46). All participants experienced diarrhea, but only 20% reported a history of vomiting. Norovirus infection was more prevalent among respondents from Debre Tabor (AOR = 3.8, 95%CI (1.1-13)) and Bahir Dar areas (AOR = 3.5, 95%CI (1.03-12)). Additionally, older adults (AOR; 7, 95% CI (1.9-27)) and under 5 children (AOR = 3.4, 95%CI (2.7-13)) were disproportionately affected compared to adults. The previous history of gastroenteritis (AOR = 3.4, 95% (CI1.4-8)) was a significant factor contributing to NoV infections. Besides, individuals with a high frequency of diarrhea (AOR = 16.3, 95%CI 6.6-40), and vomiting (AOR = 3.2, 95%CI 1.5-7) were more likely infected. Conclusions: The prevalence of NoV was considerably high with the predominance of NoV-GII. The positivity rate was higher among the extreme age groups and varied across the study areas. To obtain a comprehensive understanding of the virus`s epidemiology and its genetic diversity further research is warranted.