By Michael Yudell

More than 3 million Americans are infected with the Hepatitis C virus, and half of them don’t even realize it? You could be one of them.

Hepatitis C is a viral infection that attacks the liver, causing liver damage and sometimes liver failure or liver cancer. It is the most common cause of cirrhosis of the liver and the reason for most liver transplants. Fifteen thousand Americans die of the disease each year.

The virus is spread through infected blood or bodily fluids. It cannot be transmitted casually; you can’t get it by shaking someone’s hand or from exposure to an infected individual’s cough or sneeze. But you can get it, as most of those infected do, through sharing needles or other injection drug paraphernalia with an infected person. Roughly one-third of injection drug users ages 18 to 30 are infected with Hepatitis C. Up to 90 percent of older drug users – and former users – are infected. Rates are higher for older users of injection drugs because risks for bloodborne diseases were poorly understood before the 1980s.

It's possible – but rare – to get Hepatitis C through sex. An infected pregnant woman can also pass the virus to her child. Before 1992, when a diagnostic blood test became available, many people were infected through blood transfusions and organ transplants.

The course of the disease varies. A small percentage will clear the virus on their own. The rest, between 75 and 85 percent, will develop chronic Hepatitis C infection, which can go undiagnosed in many patients for as long as 20 to 30 years.

"Most urban communities like Philadelphia don't know the true scope of Hepatitis C because it is still so hidden," said Stacey Trooskin, who studies Hepatitis C as an infectious disease fellow at the Hospital of the University of Pennsylvania. But Trooskin, who will join the division of infectious diseases at the Drexel University College of Medicine in July, acknowledges that new rapid testing "allows us to go out into the community to test for the virus with good linkages to care, while also providing Hepatitis education and awareness."

Because so many Americans are not aware of their Hepatitis C status, it is imperative that those at risk get tested. Trooskin says, "We want to diagnose folks," said Trooskin, "so we can treat them and prevent progression to liver disease. The treatments that we have now for Hepatitis C can cure more than half of those infected and there are even better treatments in development."

To help people determine their risk status, the Centers for Disease Control and Prevention has developed an online Hepatitis risk assessment tool. If you think you might be at risk, this Saturday, May 19, is “National Hepatitis Testing Day,” and there are free testing clinics around Philadelphia and plenty of other locations.

Alex Shirreffs, the adult viral hepatitis prevention coordinator at the Philadelphia Department of Public Health, told me last week that the testing is easy, quick, and free, and that results will be shared confidentially with those tested. If you are in Philadelphia, consider getting tested for Hepatitis C at one of the following sites on Saturday:

You can also get tested Saturday for Hepatitis B, another potentially deadly form of Hepatitis, at:

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