RESUMO
Investigation of hepatitis A (HA) outbreak developed in 2005 among workers of food stores networkwas performed using conventional epidemiologic diagnostics as well as methods of molecular epidemiology. In 14 of 15 ill persons, using polymerase chain reaction, HAV RNA was detected by PCR in serum obtained on 2 - 25 day of illness (mean - 9.3 days). In 10 cases it was possible to determine nucleotide sequence of VP1/VP2 region of HAV genome and perform phylogenetic analysis of obtained isolates. It was determined that all isolates belonged to subgenotype IA, had high degree of homology and grouped in one cluster. These findings demonstrate their descendance from one source of infection, which, with high degree of probability, was the cook who made salads from fresh vegetables. HAV strain, which caused this epidemic outbreak circulates in Saint Petersburg for a long time and was already detected in 2004. Importance of vaccination against HA for persons working in manufacturing and distribution of food and use of molecular epidemiologic methods of surveillance for this infection is underlined.
