True regarding infectivity period of hepatitis A: September 2009

Ans. D: 2-3 weeks before and 1 week after the onset of jaundice HAV is a 27nm RNA hepatovirus (picornavirus family) that is inactivated when is boiled during one minute, incubated with formaldehyde or exposed to UV radiation. It is transmitted by fecal-oral route. The incubation period from the time of exposure to hepatitis A virus (HAV) to the appearance of symptoms is around 28 days (range 3 weeks to 6 weeks). HAV is spread by ingestion of contaminated water and foods and is shed in the stool for 2-3 weeks before and 1 week after the onset of jaundice. Thus, close personal contact with an infected individual or fecal-oral contamination during this period accounts for most cases and explains the outbreaks in institutional settings such as schools and nurseries, and the water-borne epidemics in places where people live in overcrowded, unsanitary conditions.