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Home About HIV/AIDS Transmission


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How HIV is (and isn't) Transmitted

A person can become infected with HIV in these ways:

  • Having sexual intercourse—vaginal, anal, or oral—with an infected person.
  • Sharing needles or syringes with an infected person.
  • Women infected with HIV can pass the virus to their babies during pregnancy or during birth. They can also pass it on when breast-feeding.
  • Some people have been infected by receiving blood transfusions, especially before 1985, when careful screening and laboratory testing of the blood supply began. However, the risk of infection from blood transfusions today is extremely rare.

A person CANNOT become infected with HIV in these ways:

  • People cannot become infected by giving blood at a blood bank.
  • HIV can not be transmitted through everyday contact with infected people at school, work, home, or anywhere else.
  • It's not possible to become infected with HIV by using the toilet, shaking hands, sharing utensils, phones, or clothing. It can't be passed on by things like spoons, cups, or other objects that someone who is infected with the virus has used.
  • One cannot become infected with sweat, tears, sneezes, coughs, or urine.
  • People cannot become infected by "dry" kissing. Although there are trace amounts of HIV present in the saliva of an infected person, there are no documented cases of HIV infection from kissing. There is a slight risk from deep or French kissing, especially if there are cuts or sores in the mouth.
  • HIV cannot be carried by a mosquito. The AIDS virus does not live in a mosquito, and it is not transmitted through a mosquito's salivary glands like other diseases such as malaria or yellow fever. You won't get it from bed bugs, lice, flies, or other insects.

How Can Someone Get HIV From Sexual Intercourse?

  • HIV can be spread through unprotected sexual intercourse with an infected partner. It can be spread from male to female, female to male, or male to male sexual contact. Female-to-female sexual transmission is possible, but rare. Unprotected sexual intercourse means sexual intercourse without correct and consistent condom use.
  • HIV may be in an infected person's blood, semen, or vaginal secretions. It is thought that it can enter the body through cuts or sores—some so small you don't know they're there—on tissue in the vagina, penis, or rectum, and possibly the mouth.
  • HIV is transmitted by anal, vaginal, or oral intercourse with a person who is infected with HIV.
  • Since many infected people have no apparent symptoms of the condition, it's hard to be sure who is or is not infected with HIV. So, the more sex partners a person has, the greater his or her chances are of encountering someone who is infected and becoming infected themselves.

How Does Someone Get HIV From Using Needles?

  • Sharing needles or syringes with an infected person, even once, is an easy way to be infected with HIV and other germs. Sharing needles to inject drugs is the most dangerous form of needle sharing. Blood from an infected person can remain in or on a needle or syringe and then be transferred directly into the next person who uses it.
  • Sharing other types of needles also may transmit HIV and other germs. These types of needles include those used to inject steroids and those used for tattooing or piercing.
  • Anyone planning to get pierced or get a tattooed should make sure they go to a qualified technician who uses sterile equipment. Don't be shy about asking questions. Reputable technicians will explain the safety measures they follow.

How Can Babies Get HIV?

  • A woman infected with HIV can pass the virus on to her baby during pregnancy or during birth. She can also pass it on when breast-feeding.
  • If a woman is infected before or during pregnancy, her child has about one chance in four of being born infected. Taking AZT during pregnancy can reduce this risk.
  • Any woman who is considering having a baby and who thinks she might have placed herself at risk for HIV infection—even if this occurred years ago—should seek counseling and testing before she gets pregnant. To find out where to go in your area for counseling and testing, call your local health department, the CDC National AIDS Hotline (1-800-342-AIDS), or visit our Online Resource Directory for Pennsylvania resources.

Blood Transfusions And HIV

  • Although in the past some people became infected with HIV from receiving blood transfusions, this risk has been virtually eliminated. Since 1985, all donated blood has been tested for evidence of HIV. All blood found to contain evidence of HIV is discarded.
  • Currently in the United States, there is almost no chance of infection with HIV through a blood transfusion.
  • People cannot get HIV from giving blood at a blood bank or other established blood collection center. The needles used for blood donations are sterile. They are used once, then destroyed.

What Are Ways To Avoid Getting HIV And AIDS?

HIV infection doesn't just happen. It can't simply be "caught" like a cold or flu. Unlike cold or flu viruses, HIV is not spread by coughs or sneezes. A good way to avoid getting HIV is to be sexually responsible: that means using condoms regularly and correctly, and being careful about choosing sex partners. Another way to avoid getting HIV is to not inject drugs, or if that is not possible, use a clean needle each and every time. For more details about preventing HIV, see the Primary Prevention section.

Not All Of The Answers Are In

HIV can not be transmitted by a kiss. Experts are not completely certain about HIV transmission through deep, prolonged, or "French" kissing. While scientists believe it is remotely possible, there has never been a known case of HIV transfusion through kissing. Most scientists agree that transmission of HIV through deep or prolonged kissing may be possible, but would be extremely unlikely.

Material adapted from: U.S. Department of Health and Human Services (1994). AIDS prevention guide: The facts about HIV infection and AIDS – Putting the facts to use (OHA 8/94 D458). Rockville, MD: CDC National AIDS Clearinghouse.

Last Updated on Tuesday, 19 October 2010 09:24