It’s hepatitis C, and it affects one generation more than any other. The majority of the people with hepatitis C were born between 1945 and 1965. According to the Centers for Disease Control and Prevention (CDC), baby boomers are five times more likely to have hepatitis C than people who belong to another generation.

Hepatitis C used to be easily transmissible through blood transfusions until 1992, when screenings became available. However, many people may have contracted the infection before that time and do not know it.

“Most people don't know they have hepatitis C because it doesn't cause symptoms until late in the disease,” said Dr. Hardeep M. Singh, medical director of the GI Endoscopy and EUS Program at St. Joseph Hospital in Orange, Calif. “Symptoms usually develop later, once the patient has evidence of cirrhosis.”

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Even when symptoms do show up, what they mean is not always obvious. “When they do develop symptoms, they are often subtle ones such as fatigue, malaise and poor appetite,” Singh said. Only as the disease progresses do more serious symptoms, such as jaundice, confusion and increased tendency for bleeding, sometimes occur.

But there’s a simple— and possibly free— screening you can get to find out for sure, and for most people, the disease is curable. Many hospitals and clinics have free hepatitis C screening days, and several health insurance plans cover the screening for baby boomer patients. Medicare also covers a one-time hepatitis C screening for free and a repeat screening annually for high-risk people, including baby boomers.

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Until recently, testing positive meant simply monitoring the disease until damage occurred— if it ever did. Anywhere from 15 to 25 percent of those infected clear the virus from their bodies on their own. For patients who do get sick, a combination of treatments that were only marginally effective and caused many side effects was usually initiated.

In 2014, the drugs Olysio and Sovaldi became available. They are usually used together and have a 95 percent cure rate. You may have heard of Sovaldi because it’s also been in the news for being on the pricier side: $84,000 for a 12-week course of treatment.

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Still, that’s not stopping insured patients from getting it. “In most cases, it is being covered,” Singh said. “Insurers have realized that even though it is expensive, this is a small price when comparing it to the ultimate cost of taking care of patients with chronic [hepatitis] C who go on to develop cirrhosis if not treated.”

Still, about 8 percent of those who are prescribed Sovaldi don’t finish the entire 12-week course of the medication, according to a study by CVS, which followed nearly 2,000 patients taking Sovaldi regimens. Study authors pointed to cost as one reason but also write that “patients with less advanced hepatitis C disease (those naïve to therapy) were markedly less likely to complete treatment than those who had previously received other hepatitis C therapies.” The researchers recommended such patients be followed closely by a doctor to avoid wasteful spending on the drug.

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Whatever is causing patients to quit the drug, most doctors agree it isn’t the side effects. “Sovaldi has minimal side effects,” Singh said. The drug’s most common side effects are mild nausea, diarrhea and a headache. He adds that these “side effects are usually manageable, and it’s exceptionally rare that the drug needs to be stopped as a result.”

Overall, the outlook for patients with hepatitis C is much better than it was just a couple of years ago. So if you’re a baby boomer who hasn’t been screened for hepatitis C yet, don’t wait. Ask your doctor about the test at your next appointment. If you do test positive, treating the infection as early as possible is key to preventing liver damage and cirrhosis.