6 Viruses That Can Cause Cancer
It’s not just smoking and genetics that can increase your risk of cancer. Catching certain viruses can too. Here’s how to protect yourself.
The truth is doctors and scientists don’t know what causes most types of cancer. Yes, some lifestyle behaviors, such as smoking, can increase your risk. Hereditary factors sometimes play a role, like if breast cancer runs in your family.
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And sometimes — in rare circumstances — cancer can be triggered by a virus.
It doesn’t happen in most people, says medical oncologist Dale Shepard, MD, PhD. But viruses can cause some cancers, particularly in people with high-risk behavior such as:
It’s not just any virus that can trigger cancer. It’s only the viruses that affect certain types of cells in your body. And even then, it’s only in certain cases, explains Dr. Shepard.
Here’s how it happens:
Most viruses, like those that cause colds and flu, never get to Step 4.
“Viruses that infect your lungs and airways, for example, don’t stay in your body for long,” says Dr. Shepard. “Even if the virus enters your airway cells and attaches to your DNA, your immune system will get rid of those faulty cells quickly. However, cells in other areas of your body, like your liver, don’t refresh as fast. Infections in those cells can become more dangerous.”
There are few viruses that have been linked to cancer. Yet some of them are quite common.
“It’s unclear why these viruses react differently in different people,” says Dr. Shepard. “There’s no way of knowing who might get cancer because of a viral infection.”
The best way to protect yourself from virus-induced cancer is to protect yourself from getting the virus in the first place. That includes avoiding high-risk behaviors, such as having unprotected sex, using illegal drugs and sharing needles.
Just as important is getting proper vaccinations, says Dr. Shepard. Vaccines are available for hepatitis B and HPV.
“These vaccines can significantly decrease your risk of infection, so they really do impact your cancer risk,” says Dr. Shepard. “Although there are no vaccines for hepatitis C and HIV, we now have medications that can minimize the amount of virus in your body if you do get infected.”