Molecular epidemiology of hepatitis A virus in Amsterdam, the Netherlands

The transmission of sporadic community-acquired hepatitis A virus (HAV) amo ng different risk groups in Amsterdam was verified by applying molecular te chniques on fecal samples. These were collected in 1997/1998 from 33 person s with HAV infection that was confirmed serologically. From 8 of these pers ons serial stool samples were collected. Nested RT-PCR targeting the VP3-VP 1 and VP1-P2a regions followed by sequence analysis established the duratio n of fecal HAV RNA excretion in stool and the epidemiological molecular rel ationships between patients. The samples of 31 patients were RT-PCR positiv e, of which 24 were positive for both regions. Fecal HAV shedding was found to occur for at least 33 days after onset of disease, which was the longes t time span tested. Sequencing showed that the hepatitis A virus subgenotyp e circulating among persons from Moroccan descent (type IB) was different f rom the subgenotype circulating among Dutch homosexual men (type IA). If th e latter is endemic in the Netherlands, its presence is of importance to th e national vaccination strategy. (C) 2001 Wiley-Liss, Inc.