Epidemiological and virological characterization of a large community-wide outbreak of hepatitis A in southern Italy

Abstract

A large outbreak of hepatitis A virus (HAV) infection occurred in 2004 in Campania, a region of southern Italy, with 882 cases reported between 1 January and 1 August. The local public health authorities and the Italian National Institute of Health carried out investigations in order to characterize the agent, identify the source of infection and the route of transmission, and implement appropriate control measures. A web-based reporting system enhanced the flow of information between public health authorities, providing real-time epidemic curves and frequency distributions. The same 1B HAV genotype was found in 90% of sera from a subset of patients with acute disease, suggesting a local common source. A case-control study in the municipality with the highest attack rate showed that raw seafood consumption, in particular if illegally sold in water, was strongly associated with HAV illness. Samples of seafood systematically collected from retailers were found contaminated by HAV.

Comparative hepatitis A seroepidemiology in 10 European countries

“…Community-wide outbreaks, often related to poor hygienic conditions have been reported, e.g. in Bulgaria, Italy, Latvia, and Slovakia [33][34][35][36][37][38]. It is evident that vaccination of risk groups in countries with high susceptibility of young and middle-aged adults needs to be continued.…”

Shifting susceptibility to hepatitis A among children and adolescents over the past decade

“…Embora seu curso seja, em geral, autolimitado, pode ocorrer em diferentes graus de intensidade, inclusive formas graves, sendo causa de morbidade significativa em países desenvolvidos e em desenvolvimento 1 . A transmissão ocorre principalmente pela rota fecal-oral, pelo contato com uma pessoa infectada, ou pela ingestão de água e alimentos contaminados, particularmente saladas, frutas e moluscos bivalves [2][3][4] . Características do vírus da hepatite A (VHA) como a estabilidade no meio ambiente, principalmente quando associado à matéria orgânica, e a resistência ao pH baixo e ao calor favorecem a transmissão por água e alimentos contaminados e também a detecção em amostras ambientais de água e esgoto 3 .…”

Ongoing outbreak of hepatitis A in Italy: preliminary report as of 31 May 2013

“…The improved health and sanitary conditions have favored a progressive decrease of the infection rate in children, and a major shift of the population at risk, with the highest incidence reported in young adults. Outbreaks were described in 1996-1997 and 2004 mainly in southern Italian regions (Apulia and Campania) and were related to the consumption of contaminated raw shellfish [5,6]. From 1997, when the incidence was 19 per 100,000 population [2] to date, a decreasing trend in the incidence of HAV has been observed, to 1.1 cases, 0.7 and 0.8 per 100,000 population in 2010, 2011, and 2012, respectively [7].…”