Human T-cell leukemia/lymphoma virus (HTLV)
HTLV is similar to HIV, another virus, but HTLV doesn’t cause AIDS. The type of HTLV related to cancer is human T-cell leukemia/lymphoma virus type 1 (HTLV-1).
Once infected with HTLV-1, a person has the infection for life. There is no treatment to get rid of the virus once you are infected. In many cases the virus does not cause symptoms or health problems.
HTLV-1 and cancer
HTLV-1 can cause an uncommon type of T-cell lymphocytic leukemia and non-Hodgkin lymphoma in adults called adult T-cell leukemia/lymphoma (ATLL). This cancer is not common in Canada and occurs mostly in Japan and the Caribbean.
People who carry HTLV-1 have a 2% to 4% lifetime risk of developing ATLL. It often takes a very long time before the person infected with the virus develops ATLL. However, only a few people who have HTLV-1 will develop ATLL.
How is HTLV spread?
HTLV-1 is spread in much the same way as HIV. Not everyone exposed to HTLV-1 becomes infected. It can be spread from a person infected with HTLV-1 to someone else by:
- having unprotected sex
- sharing needles, syringes or other equipment for injecting drugs
- a transfusion with contaminated blood or blood products
- an infected mother to a child during birth or through breastfeeding
Canadian Blood Services tests every blood donation for HTLV-1, so the risk of getting an HTLV-1 infection through a blood transfusion is very low. Mothers infected with HTLV-1 have a 10% to 30% chance of passing the virus on to their children. The risk is reduced if the mother doesn’t breastfeed.
How to test for HTLV-1?
A blood test can be done to check for antibodies to the virus.
How to reduce your risk
Right now, there is no vaccine that prevents HTLV-1 infection. To help reduce your risk of HTLV-1 infection, follow these tips.
Practise safer sex.
If you are sexually active, use a condom to help protect against HTLV-1, as well as other sexually transmitted infections.
Protect yourself from infected blood or body fluids.
Don’t share needles or other drug-use equipment. If you inject drugs, take part in a needle exchange program.