Epidemiology of Hepatitis A in Catalonia, 2001-2006

Abstract

It is a retrospective and comparative descriptive study whose main objective is to describe the epidemiological characteristics of hepatitis A in Catalonia, in the period 2001-2006 and to assess the influence of the Moroccan population. A total of 1,378 cases of hepatitis A were reported, of which 1,217 confirmed or probable cases (88.3%) were included in the study. The average annual rate found was 3.0 / 100,000 inhabitants (range 1.7 to 3.9). 63.8% were men and the median age was 27 years old (0-89), with the group with the highest rate being 5 to 9 years old (11.8). The most frequent antecedents of risk were: travel to an endemic area (22.8%), non-sexual partner (14.5%), risky food consumption (11.1%) and homosexual contact (5.8%).
Gamma globulins were administered and the contacts of the cases were vaccinated in 13.8%, being higher in the cases notified within the first 14 days (28.3%) than in those notified after 14 days (12.4% p<0.001). The associated cases were younger than the sporadic ones (median 22 years versus 28 years p<0.001), attended more preschool centers (12.8% versus 4.7% p<0.001) and had more contact with children under 3 years (14.0% versus 8.7% p=0.005). The incidence rate for the years 2005 and 2006 was 2.2 cases per 100,000 h. in the Spanish and 9.7 in the Moroccans. The cases of Moroccan origin were younger than the Spanish (median 7 years versus 30 years, p<0.001) and had more history of travel to an endemic area (62.8% versus 14.6% p<0.001). The cases with a history of travel to Morocco were younger than the Spanish, attended preschool more frequently (19.4% versus 3.7%), presented less risky food consumption (1.0% versus 11.6% p<0.001) and were cases associated with higher frequency (65.3% versus 36.3% p<0.001). In Catalonia, hepatitis A is more common in young children and young adults. Person-to-person contact is the predominant mechanism of transmission. The cases of Moroccan origin and the cases with a history of travel to Morocco are younger and could be important in maintaining the circulation of the virus among the population under 10 years of age.