Hepatitis B immune status of non-injecting drugusers 18- to 25-years-old in Puerto Rico

Ilicit drug users are the population group at highest risk of HBV infection in most Western countries. In this study we assessed hepatitis B virus (HBV) immune status in a cohort of young non-injecting drug users in Puerto Rico.

Subjects were eligible if they were 18- to 25-years-old, had never injected any drugs, and had recently used heroin or cocaine. A total of 541 subjects were recruited from community settings during 2004 and 2005. Subjects were interviewed and tested for HBV immune status and infection.

Overall, 36.6% showed evidence of HBV immunity. Among subjects not HBV immune, 63.0% reported being vaccinated against HBV. Rates of HBV immunity were 47.6% among subjects who were 12-years-old or less in 1995 when mandatory school verification of HBV vaccination was established and 23.0% among those who were older than 12 in 1995 (p<.001). HBV immunity was 52.5% among non intravenous drug user who were 12-years-old or less in 1995 if they had not dropped out of school before the 8th grade compared to 23.9% (p<.001) among those who did drop out before the 8th grade.

Mandatory school verification of HBV vaccination seems to have had a substantial effect in increasing coverage among young illicit drug users. However, the impact of mandatory school verification appears to be limited by the fact that many illicit drug users drop out of school early after completing the primary level.