Prevalence of hepatitis A antibodies in schoolchildren in Catalonia (Spain) after the introduction of universal hepatitis A immunization

Abstract

The objective of this study was to investigate the prevalence of hepatitis A antibodies (anti-HAV) in schoolchildren in Catalonia and to compare it with the rates found in previous studies. Sera from a representative sample of 1,342 children aged between 6 and 15 years, recruited in 2001, were tested for anti-HAV. The results were related to sociodemographic variables and vaccination history. The overall prevalence of anti-HAV was 51.4%. The prevalence was 5.5% in non-vaccinated children, similar to that found in a 1996 study, and 96.6% in vaccinated children. The prevalence of anti-HAV in non-vaccinated children increased significantly with age, reaching 11.6% in the 13-15 years age group. The prevalence of anti-HAV was higher in children born outside Catalonia than in those born in Catalonia (16.1% vs. 5.0%, P = 0.02). The expected continuation in the decline in the prevalence of anti-HAV in non-vaccinated schoolchildren, observed in Catalonia since 1986, was not found in 2001. The rate of anti-HAV in 2001 was slightly higher than in 1996, although the difference was not statistically significant (5.5 and 3.5%, respectively). This could be explained by the increased number of recent immigrant children born outside Catalonia, mainly in countries where hepatitis A is highly endemic.

Marked decrease in the incidence and prevalence of hepatitis A in the Basque Country, Spain, 1986–2004

“…2 cases/100 000 inhabitants in 1996-1998 to 2 . 6 cases/100 000 inhabitants in the following 3 years [24]. This tendency is similar to that observed in the Basque Country where there is no policy of universal vaccination.…”

“…with high vaccination coverage is incorporated into the population [24], whereas in the Basque Country the susceptibility of the population to hepatitis A increases each year.…”

Demographic Study on Hepatitis A Infections among Outpatients of Selected Hospitals within Kaduna Metropolis, Nigeria

“…This could probably be due to improvements in personal hygiene and the ability to avoid contaminated foods and drinks thereby complying with personal hygiene by adults. On the contrary, previous studies in other countries of the world have reported high prevalence for anti-HAV antibody among children such as: 51.4% among schoolchildren in Catalonia Spain, 60% prevalence among school children in central Tunisia and 61.4% among children in Egypt [27][28][29]. These dissimilarities may not be unconnected from the fact that prevalence rates for HAV antibody varies from one country to another and even within the same country from city to city probably due to variations in socio-economic status [26].…”

Interchangeability of a hepatitis A vaccine second dose: Avaxim 80 following a first dose of Vaqta 25 or Havrix 720 in children in Turkey

“…Children with unrecognised infection in regions of high endemicity also play an important role in HAV transmission. Significant reductions in the incidence of hepatitis A disease have occurred following the universal vaccination of young children in Israel and in Catalonia [10,11]. Hepatitis A vaccination of young children has been added to the national schedule in Argentina, also a country with a "transitional" pattern of endemicity [24].…”

“…In many regions of Turkey, the peak age at infection is shifting from childhood to adolescence or adulthood [3,12,16,26,27,34]. The epidemiologic conditions in Turkey are, thus, similar to other countries with intermediate endemicity, in which routine childhood hepatitis A vaccination has begun or is being considered [10,11,23].…”