Comparison of the Prevalence and Risk Factors of Hepatitis A in 10 to 18-Year-Old Adolescents of Sixteen Iranian Provinces: The CASPIAN-III Study

BACKGROUND Hepatitis A is a common health concern both in developing and developed countries. Hygienic and socioeconomic parameters deeply impact the prevalence and transmission of this disease. Evaluating the epidemiological distribution and risk factors for Hepatitis A virus (HAV) is necessary for policy makers to improve local and national preventive measures. OBJECTIVES The aim of this study was to compare the prevalence of hepatitis A infection in a sample of Iranian adolescents living in different provinces of Iran and to assess its family- and community-related risk factors. METHODS In this cross-sectional study, serum samples of 10 to 18-year-old adolescents, who were studied in a national health survey, were examined for anti-HAV antibodies. A total of 2,494 subjects were included from 16 provinces by multistage random cluster sampling. Demographic and socioeconomic factors related to HAV transmission were extracted by valid questionnaires. A multilevel analysis using mixed-effects logistic regression (melogit) was used to evaluate the association of risk factors with HAV infection. RESULTS The weighted prevalence of HAV varied significantly across the studied provinces (P = 0.001), ranging from 50.43% in the Fars province to 78.81% in Markazi province. HAV was significantly more prevalent in children whose mothers worked outside of the home (OR, 1.73; 95% CI, 1.14-2.62; P = 0.009). CONCLUSIONS The risk of symptomatic HAV infection is considerable in adolescents of all studied provinces; thus, universal HAV vaccination is recommended for all adolescents, regardless of their socioeconomic level. However, the risk is higher in some provinces, which seem to be transitioning from intermediate to low endemicity.