Genetic Diversity and Geographical Distribution of HAV Subgenotype 1A

Abstract

Hepatitis A virus (HAV) is a significant health concern around the world. It is considered the most common cause of acute liver infection worldwide. Annually, more than a million clinical cases of HAV are reported. This virus is usually spread through person-to-person contact via the faecal-oral route, but outbreaks are frequently caused by contaminated water and food. It is a highly stable virus that may persist in water for up to ten months. Here, we constructed a phylogenetic tree based on 163 sequences of the HAV VP3 gene and analysed the diversity within subgenotype 1A. The sequences were selected and downloaded from the GenBank database according to sequences with 100% query coverage and identity-less than 90%. The phylogenetic tree results showed that HAV subgenotype 1A has unique geographic distributions globally, including Asia, Europe, North and South America, and Africa. However, we suggested that more primers should be designed to capture a wider range of diversity and entropy plot analysis could help. The geographic distribution can be influenced by many factors such as travel patterns, food imported, poor sanitation and hygiene. In addition, some newly developed methods for detecting HAV in clinical and environmental samples have been discussed in this paper that can be used for future studies.