Editorial

Following a review of acute hepatitis A and the objectives and methods of its surveillance by the Regional Health Agencies (ARS) and the French Institute for Public Health Surveillance (InVS), this "Hepatitis A Special" Health Surveillance Bulletin presents the regional results of surveillance of reported cases in Picardy and Nord-Pas-de-Calais since hepatitis A became a notifiable disease in November 2005. During this period, a very large community-based outbreak affected the Nord department. It spanned the years 2008 and 2009 and resulted in the reporting of nearly 500 confirmed cases. This episode illustrates the epidemic risk posed by the hepatitis A virus (HAV) and the value of vaccination around cases as a preventive measure complementary to enhanced hygiene practices.In May 2011, an epidemiological investigation of three cases of hepatitis A with a direct or indirect link to a hospital in the Oise department led to the detection of a cluster of cases linked to attendance at a daycare center and enabled the rapid implementation of appropriate preventive measures.These two events demonstrate the importance of reporting hepatitis A cases as early and as comprehensively as possible by laboratory technicians and clinicians to limit secondary transmission of HAV, particularly through vaccination of contacts and the strengthening of hygiene measures in community settings.