Comparative hepatitis A seroepidemiology in 10 European countries

Abstract

The WHO recommends hepatitis A virus (HAV) immunization according to level of transmission and disease burden. We aimed to identify susceptible age groups by standardized serosurveys to inform HAV vaccination policy in participating countries: Belgium, Czech Republic, England, Finland, Germany, Italy, Lithuania, Malta, Romania, and Slovakia. Each country tested national serum banks (n = 1854-6748), collected during 1996-2004, for anti-HAV antibodies. Local laboratory results were standardized to common units. Forty-one per cent of those aged <30 years and 6% of those aged ≥30 years were susceptible to HAV in Romania; compared to 70-94% and 26-71%, respectively, elsewhere. Romania reported high HAV incidence in children and young adults. Other countries reported HAV disease primarily in older risk groups. The results suggest low level of HAV transmission in most of Europe. Romania, however, appeared as an area with intermediate transmission. Vaccination of risk groups in countries with high susceptibility of young and middle-aged adults needs to be continued.

Fig. 1.

Seroprevalence of HAV in the participating countries by birth cohort: (a) Czech Republic, Finland, Germany, England; (b) Belgium, Italy, Malta, Slovakia; (c) Lithuania and Romania. The data in these panels are based on the following age groups: 0–4, 5–9, 10–14, 15–19, 20–24, 25–29, 30–34, 35–39, 40–49, 50–59, and ⩾60 years. The data points represent the median birth year of each group, except for the end points which represent the end point birth year and all those born before that.

Fig. 2.

Characteristics of HAV seroepidemiology in Romania. HAV seroprevalence in 2002 and age-specific incidence in (a) 2002, and (b) overall incidence over time. In panel (a), the age-specific incidence data are based on the following age groups: <1, 1, 2, 3, 4, 5–9, 10–14, 15–19, 20–24, 25–34, 35–44, 45–54, 55–65, 65–74, 75–84, ⩾85 years, and the age-specific prevalence data are based on the following age groups: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20–24, 25–29, 30–34, 35–39, 40–49, 50–59, ⩾60 years. The data points represent the median age of each group, except for the end points, which represent the end point age and all those older than that.

Fig. 3.

Characteristics of HAV seroepidemiology in Finland. (a) HAV seroprevalence in 1997–1998, and age-specific incidence in 1997–1998 (combined) and in 2002 (when HAV outbreak in intravenous drug users occurred in Finland. (b) Overall incidence over time.