HIV test and HTLV-1


Question:

Doctor, If someone has HTLV-1 but do not have HIV, what would be the result of HIV Test. Because I heard that HIV & HTLV-1 both produces same kind of antigens. I am afraid HIV Test may detect HTLV-1 even if one does not have HIV. Thanks


Mr. Sowadsky's Response:

Hi. Thank you for your question. Cross reactions in tests between HIV and HTLV-I can happen, but are not very common. HIV and HTLV-I vary significantly in terms of their structure and genetics. However, on occasion, there may be a small amount of cross-reactivity on antibody tests. This is because these two viruses share a single protein (antigen) in common. Other than this one protein, these viruses vary significantly from each other. In fact, they vary so much, that people with HTLV-I (without having HIV), will usually have a negative HIV test. On occasion, they may get an indeterminate HIV test, but this is not very likely. A person with HTLV-I (but not having HIV), will not test positive on an HIV test. These two viruses are different enough from each other, that the tests can easily distinguish between them. Therefore, infection with HTLV-I should not cause false positive HIV tests.

However, HTLV-I and HTLV-II are very similar viruses, and tests can sometimes have difficulty distinguishing between these two viruses. Special tests have to be done to distinguish between HTLV-I and HTLV-II. However, there isn't any problem for tests to distinguish between the HTLV viruses and HIV.

Since we're on the subject of the HTLV viruses, let me review with you all about HTLV-I and HTLV-II. As you will see, they share similarities with HIV, but are also very different.

HTLV-I

What is HTLV-I?

This is a virus that can cause a type of leukemia (cancer of the white blood cells) called Adult T-Cell Leukemia. This virus can also cause problems with the nervous system. Not everyone with HTLV-I will get these diseases, but in those who do, it can be very serious. These diseases don't usually strike until years after infection. HTLV-I does not cause AIDS!

How do you get HTLV-I?

HTLV-I is transmitted:
  1. through vaginal intercourse, anal intercourse, and giving oral sex. Blood, semen and vaginal secretions contain high concentrations of this virus.
  2. by sharing needles contaminated with blood. This includes IV drug needles and tattoo needles.
  3. from mother to child during pregnancy, and possibly through breast feeding.
  4. rarely through a blood transfusion (In the United States, the blood supply is tested for this virus and infected blood is thrown away).

What are the symptoms of HTLV-I infection?

Most people infected with this virus show no symptoms at all. However, when symptoms begin, they usually start many years after infection. When this virus affects your nervous system, it can cause incontinence (inability to control your bladder), difficulty in walking, lower back pain, and impotence. Luckily, most people with HTLV-I do not show these neurological symptoms at all.

The symptoms of leukemia can begin 20 years or more after infection. Some symptoms of leukemia are fatigue, swollen glands, fever, skin lesions, and flu-like symptoms. Because this type of cancer affects the immune system, a person is more susceptible to various types of diseases called opportunistic diseases. These diseases only make you sick when the immune system is not functioning properly.

How can you prevent transmitting the virus to others?

Abstinence (not having sex or using drugs) is the only 100% effective way to prevent infection. If you do have sex, use a latex or polyurethane condom every time you have sex. Don't share IV or tattoo needles with anyone else. Do not donate blood, organs, or semen. It is important that you tell your sexual partners that you have this virus before you have sex. This is important since condoms do not provide 100% protection against the virus. However condoms, used consistently and correctly, do significantly reduce the risk of infection. Remember, you can transmit the virus even if you have no symptoms at all.

What is the link between HTLV-I and HIV (the AIDS virus)?

HTLV-I does not cause AIDS! However, both viruses are transmitted the exact same way. Therefore, if you have tested positive for HTLV-I, you may want to be tested for the HIV virus as well. Both of these viruses infect the same cells of the immune system (CD4 cells). However, HIV kills CD4 cells, whereas HTLV-I can transform these cells into cancer cells. Preliminary studies show that in persons infected with both HTLV-I and HIV at the same time, full-blown AIDS may progress faster.

Can HTLV-I be cured?

Because this is a virus, the infection cannot be cured. People diagnosed with Adult T-Cell Leukemia are treated with chemotherapy. People with the neurological disease are sometimes treated with corticosteroids. These treatments do not always work however. There are no established treatments against the HTLV-I virus itself, although AZT (Retrovir), in combination with other drugs, has been tried experimentally with mixed results.

HTLV-II

What is HTLV-II?

HTLV-II is a virus found in blood, semen and vaginal secretions. As far as we know so far, it is not known to cause any specific disease. HTLV-II does not cause AIDS!

How do you get HTLV-II?

HTLV-II is transmitted:
  1. through vaginal intercourse, anal intercourse, and giving oral sex. Blood, semen and vaginal secretions contain high concentrations of this virus.
  2. by sharing needles contaminated with blood. This includes IV drug needles and tattoo needles.
  3. from mother to child during pregnancy, and possibly through breast feeding.
  4. rarely through a blood transfusion (In the United States, the blood supply is tested for this virus and infected blood is thrown away).

What are the symptoms of HTLV-II Infection?

As far as we know right now, HTLV-II does not cause any symptoms. However, if you have any symptoms that do not go away after 2 or more weeks, or are acutely very severe, it is always important that you see a health care provider.

What is the link between HTLV-II and HIV (the AIDS virus)?

HTLV-II does not cause AIDS! However, both viruses are transmitted the exact same way. Therefore, if you tested positive for HTLV-II, you may want to be tested for the HIV virus as well.

What is the link between HTLV-I and HTLV-II?

HTLV-I and HTLV-II are transmitted the same way. HTLV-I causes a type of leukemia (cancer of the white blood cells) called Adult T-Cell Leukemia. The HTLV-I virus can also cause problems with the nervous system. The test that is used to diagnose HTLV-II infection can usually tell you if you're infected with the HTLV-I virus as well. Check with your doctor to see if you were tested for the HTLV-I virus.

How can you prevent transmitting the virus to others?

Since we don't know whether this virus is harmful or not, it is best not to expose others to the virus. Abstinence (not having sex or using drugs) is the only 100% effective way to prevent infection. If you do have sex, use a latex or polyurethane condom every time you have sex. Don't share IV or tattoo needles with anyone else. Do not donate blood, organs, or semen. It is important that you tell your sexual partners that you have this virus before you have sex. This is important since latex condoms do not provide 100% protection against the virus. However condoms, used consistently and correctly, do significantly reduce the risk of infection.

Can HTLV-II be cured?

Because this is a virus, the infection cannot be cured.

If you have any further questions, please call the Centers for Disease Control at 1-800-342-2437 (Nationwide).
. I'm glad to help!


Rick Sowadsky MSPH CDS