Most people think of viruses as small living things that bring on a nasty summer cold. But you might be surprised to learn that some viruses can lead to cancer.
Keep in mind that even if you're infected with a virus that's linked to cancer, it doesn't mean you'll get the disease for sure. And there are things you can do, from vaccines to lifestyle changes, to prevent yourself from catching the virus in the first place.
Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV)
HBV and HCV can cause a liver infection that can sometimes lead to liver cancer. You pick up these viruses if you share needles used to inject drugs, have unprotected sex, or get a transfusion with contaminated blood.
Doctors treat HBV and HCV infections with medicine. You can often get rid of HCV after a few months of treatment. Medication doesn't cure HBV, but it can lower the chance of liver damage and liver cancer.
There's a vaccine to prevent HBV, but not HCV. Those with higher chances of getting HBV should get vaccinated. That includes people who have HIV, inject illicit drugs, or are health care workers.
Kaposi Sarcoma-Associated Herpesvirus (KSHV)
KSHV is a herpes virus that can cause Kaposi sarcoma, a cancer of the blood vessels, as well as two types of lymphoma. You're more likely to get cancer from KSHV if you have a weakened immune system -- your body's defense against germs -- because you had an organ transplant, get chemotherapy, or have AIDS.
The virus can be spread during sex, so you can avoid catching it if you use condoms and limit how many sexual partners you have. It may also be spread through blood and saliva.
Merkel Cell Polyomavirus (MCV)
MCV is a common virus that infects the skin. It usually doesn't cause symptoms or lead to cancer. But in some people, MCV causes a rare skin cancer called Merkel cell carcinoma.
To help prevent Merkel cell carcinoma and other skin cancers, one important thing to do is use sunscreen with an SPF of at least 30 when you go outside.
Human Papillomavirus (HPV)
HPV is a group of more than 200 viruses, and at least a dozen of them can cause cancer. HPV can spread during vaginal or anal intercourse and oral sex.
HPV often goes away on its own and doesn't cause any health problems. Some people stay infected, though. If they have the HPV that causes cancer, it can lead to cancers of the cervix, vulva, vagina, penis, anus, tonsils, or tongue.
HPV vaccines can keep you from getting infected with the virus. Health officials recommend them for everyone from ages 9 to 26 if they have not been vaccinated previously. There is a vaccine approved by the FDA for age 27-45 but you should discuss with your doctor if this vaccine is appropriate for you.
Human Immunodeficiency Virus Type 1 (HIV-1, or HIV)
HIV spreads through unprotected sex and infected needles. An unborn baby can also catch it during pregnancy, and a mother with HIV can spread it to a baby if they breastfeed.
People with HIV have a weakened immune system and have a greater chance of getting cancers such as:
- Kaposi sarcoma
- Non-Hodgkin's lymphoma
- Cervical cancer
You can help prevent HIV if you use a condom during sex and don't share needles used to inject drugs. You can also use HIV prevention medicines such as pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP).
While there's no cure, you can control HIV with treatment.
Human T-Cell Lymphotropic Virus Type 1 (HTLV-1)
HTLV-1 infects T cells, which are a type of white blood cell. It can cause leukemia and lymphoma.
HTLV-1 spreads several ways, including:
- From mother to child during birth or through breastfeeding
- Sharing needles with infected people
- Organ transplant
- Sex without condoms
About 2% to 5% of people who have the virus get adult T-cell leukemia or other health conditions. It's not clear why some people get leukemia and others don't. Symptoms and how it develops are different for each person.
There isn't a cure or treatment for HTLV-1. It's a lifelong condition. But regular checkups can lower your chances of cancer.
To help prevent spreading the virus, use condoms and limit how many sexual partners you have. If you're a woman and you're infected, you shouldn't breastfeed.
Epstein-Barr Virus (EBV)
EBV is a common virus. Most people get infected with it at some point in their lives. Most of the time, people with EBV stay healthy and don't have symptoms.
For others, EBV can cause mononucleosis and other more serious conditions, from viral meningitis to pneumonia.
Several cancers are linked with EBV as well:
- Burkitt's lymphoma
- Nasopharyngeal carcinoma (cancer of the upper throat)
- Hodgkin's and non-Hodgkin's lymphoma
- T-cell lymphomas
- Post-transplant lymphoproliferative disorder (too many white blood cells)
- Leiomyosarcoma (cancer in the soft tissue)
You can help protect yourself from EBV by not kissing or sharing drinks, food, or personal items with someone who has the virus.
There's no specific treatment if you have EBV, but you can ease symptoms if you drink plenty of fluids, get rest, and take medicines for pain and fever.