Changing Epidemiology of Hepatitis A and Hepatitis E in Hong Kong

Hepatitis A virus (HAV) and hepatitis E virus (HEV) are both transmitted by faecal-oral route. More local data on hepatitis A relative to hepatitis E was available over the last decades. Hong Kong is of intermediate endemicity for HAV []. Since 1988 with the breakdown of reported hepatitis according to aetiologic agents, the largest epidemic of hepatitis A occurred in 1992, with over 3,500 cases reported to the Department of Health (DH). This represents a notification rate of 63 per 100,000 population and since then, a gradual declining trend in HAV incidence has been observed. Since 2005, the annual number of notifications was below 100 and the respective numbers in the last 5 years were: 68 (2007), 71 (2008), 64 (2009), 65 (2010) and 46 (2011). Overall, case fatality rates from hepatitis A had been low and ranged between 0 and 0.7%. A seasonal pattern of acute hepatitis A is present, with cases more commonly reported between January and May each year. Over the years, there is an overall increase in age, with decrease in proportion of 15-24 age group people but increase in those >25 years old. The discernible decline in hepatitis A led to a parallel declining trend in overall reported viral hepatitis since 2002.