Hepatitis C virus (HCV) infection rates may be declining nationwide, but they’ve been rising for a decade among Massachusetts teens and young adults, Reuters reports. Researchers at the Massachusetts Department of Public Health (MDPH) report that HCV rates increased among whites aged 15 to 24 from 2002 to 2009, likely due to an uptick in the use of injected heroin.

According to a May 6 report published in the U.S. Centers for Disease Control and Prevention’s (CDC’s) Morbidity and Mortality Weekly Report (MMWR), there has been an overall decline in rates of newly reported HCV infections in the State of Massachusetts: 181 per 100,000 people in 2002 to 128 cases per 100,000 people in 2006. There was, however, an increase in newly reported HCV infections-65 to 113 cases per 100,000 people-between 2002 and 2009 among young Massachusetts residents between the ages of 15 and 24.

To explore this disparity, MDPH and CDC staff examined data from 1,196 people between 15 and 24 years of age diagnosed with confirmed or probably HCV infection between 2007 and 2009. Seventy two percent of the patients reported either past or present use of injected drugs, notably heroin.

An editorial from the CDC accompanying the MMWR report adds weight to the suggestion that rising HCV rates among young people in Massachusetts can be tied to increasing rates of injection heroin use. According to law enforcement reports, the CDC writes, first-time heroin usage had climbed from 100,000 new users in 2002 to 180,000 in 2009.