The CDC recorded a 150 percent increase in acute hepatitis C cases from 2010 to 2013, said Dr. Jonathan Mermin, director of the National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention. Health officials say high rates of hepatitis C are a key indicator of needle-sharing and a potential HIV outbreak.
    "The situation in Indiana should serve as a warning that we cannot let down our guard against these deadly infections," Mermin said.
    The advisory urges health departments to review recent data on HIV and hepatitis C diagnoses, overdose deaths, drug arrests and admissions for drug treatment to identify communities at risk for unrecognized clusters of HIV and hepatitis C infections.
    Hepatitis C, which is most commonly spread through the sharing of drug needles, can lead to liver cancer and and is the leading reason for liver transplants. The virus also can trigger damage in other parts of the body, though it can take decades for symptoms to emerge. HIV spreads among drug users mainly through unprotected sex and the sharing of needles.
    Indiana typically sees about 500 new HIV cases a year, health officials have said. The Scott County outbreak is just the "tip of the iceberg" of a national opiate abuse problem that puts people at high risk of infectious diseases, Mermin said.
    Adams said the state has spent more than $2 million on efforts to fight the outbreak, which include testing, awareness campaigns, a limited needle-exchange program and an outreach center that allows people to sign up for health insurance and other services.