Human T cell Lymphotropic Viral Infection
Condition
(HTLV; HTLV-I; HTLV-II)
Definition
Human T cell lymphotropic virus (HTLV) infects a type of white blood cell called a T-cell or T-lymphocyte. White blood cells are a type of cell that helps fight infection.
HTLV is a type of retrovirus that can cause cancer. It is different than the retrovirus that causes AIDS .
Causes
HTLV infection is caused by a specific virus.
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Risk Factors
There are two types of HTLV: HTLV-I and HTLV-II.
Things that may raise the risk of getting HTLV-I are:
- Living in an area where the virus is common, such as Southern Japan, Caribbean countries, parts of Africa and South America, the Middle East, and Melanesia
- Being breastfed by someone who has the infection
- Getting a blood transfusion or transplant in the US before 1988
- Having unprotected sex with someone who is infected with the virus, who is an injection drug user, or who is from an area where the virus is common
- Injection drug use
People of American Indian or African Pygmy descent are at greater risk for HTLV-II.
Things that may that raise the risk of getting HTLV-II are:
- Being breastfed by an infected mother
- Getting a blood transfusion in the US before 1988
- Having unprotected sex with someone who is infected with the virus or who is an injection drug user
- Injection drug use
Symptoms
Most people with HTLV do not have symptoms, but having the virus puts people at higher risk of certain health problems.
People with HTLV-1 may develop:
- Adult T-cell leukemia (ATL). This disease involves cancer of a specific group of white blood cells.
- Opportunistic infections, including Strongyloides stercoralis hyperinfection
- Inflammation of the eyes, joints, muscles, lungs, or skin (rare)
A person infected with HTLV-I or HTLV-II, may also develop a disorder of the nervous system known as HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It can cause weakness, numbness and stiffness in the legs, and problems walking.
Diagnosis
The doctor will ask about symptoms and past health. A physical exam will be done.
HTLV infection can only be diagnosed with a specific blood test. The presence of HTLV antibodies is a sign of infection with the virus.
Treatment
There is no treatment that can remove the virus from the body. Treatment is aimed at managing HTLV-associated diseases and reducing their symptoms.
To prevent spreading HTLV to others:
- Do not donate plasma, bone marrow, organs, semen, or breast milk.
- Do not breastfeed.
- Avoid unprotected sex.
- Avoid sharing needles or syringes.
Prevention
To lower the risk of HTLV infection:
- Avoid unprotected sex.
- Do not share needles or syringes.
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
CANADIAN RESOURCES:
The Canadian Hematology Society
Health Canada
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
CANADIAN RESOURCES:
The Canadian Hematology Society
Health Canada
References
- Human T-cell lymphotropic virus type 1 (HTLV-1). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/human-t-cell-lymphotropic-virus-type-1-htlv-1.
- Human T-lymphotropic virus (HTLV). New York State Office of Alcoholism and Substance Abuse Services website. Available at: https://oasas.ny.gov/AdMed/FYI/HTLV-FYI.cfm.
Contributors
- David L. Horn, MD, FACP
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