Human immunodeficiency virus (HIV) is a virus that attacks the immune system. HIV can cause acquired immunodeficiency syndrome (AIDS), a diagnosis of late-stage HIV infection that severely weakens the immune system and can be fatal, if left untreated.

One person can transmit HIV to another under certain circumstances. Understanding the facts rather than believing myths about HIV transmission could prevent both the spread of misinformation and the transmission of HIV.

HIV may be transmitted through certain body fluids that are capable of containing high concentrations of HIV. These fluids include blood, semen, vaginal and rectal secretions, and breast milk.

HIV is transmitted when fluids from a person who has measurable amounts of the virus in their body (HIV-positive) pass directly into the bloodstream or through the mucous membranes, cuts, or open sores of a person without HIV (HIV-negative).

Amniotic and spinal cord fluids can also contain HIV and could pose a risk to healthcare personnel who are exposed to them. Other bodily fluids, such as tears and saliva, CANNOT spread the infection.

HIV exposure can occur during sexual intercourse. Vaginal sex and anal sex have risks of HIV transmission, if exposed. There have been reported cases of HIV transmission via oral sex, but it is considered extremely rare compared to transmission during intercourse.

Anal sex maintains the highest risk of transmission among sexual activity. Bleeding is more likely during anal sex due to the fragile tissues that line the anus and anal canal. This allows the virus to enter the body more easily even if visible bleeding is not observed, as breaks in anal mucosa may be microscopic.

HIV can also be transmitted from a woman to child during pregnancy, delivery, and through breastfeeding. Any circumstance in which someone is directly exposed to the blood of a person who is living with HIV and has a detectable or measurable viral load can be a risk factor. This includes sharing needles for injection drug use or getting a tattoo with contaminated instruments. Safety regulations generally prevent blood transfusion-related infection.

The risk of being infected with HIV from a blood transfusion, other blood products, or organ donation is now extremely rare in the United States. The Public Health ServiceTrusted Source started testing all donated blood for HIV in 1985, after medical personnel realized that donated blood could be a source of HIV infection. Tests that are more sophisticated were put into place in the 1990s to further ensure the safety of donated blood and organs. Blood donations that test positive for HIV are safely discarded and do not enter the U.S. blood supply. The risk for transmission of HIV during a blood transfusion is estimated conservatively to be 1 in 1.5 millionTrusted Source, according to the Centers for Disease Control and Prevention (CDC).

There is no need to be afraid that kissing or having casual contact with someone who living with HIV can transmit HIV. The virus doesn’t live on the skin and can’t live very long outside the body. Therefore, casual contact, such as holding hands, hugging, or sitting next to someone who is living with HIV, will not transmit the virus.

Closed-mouth kissing isn’t a threat either. Deep, open-mouthed kissing can be a risk factor when it involves visible blood, such as from bleeding gums or mouth sores. However, this is extremely rare. Saliva does not transmit HIV.

Scratching and spitting aren’t transmission methods for HIV. A scratch doesn’t lead to an exchange of bodily fluids. Using gloves when drawing blood helps protect against transmission if accidental exposure to infected blood occurs. A bite that doesn’t break the skin can’t transmit HIV either. However, a bite that opens the skin and causes bleeding can — although there have been very few cases of a human bite causing enough trauma to skin to transmit HIV.

You can protect yourself from HIV infection by practicing safer sex methods, including using condoms and taking pre-exposure prophylaxis (PrEP).

Use a new condom every time you have vaginal, oral, or anal sex. Remember to use water-based or silicon-based lubricants with condoms. Oil-based products can break down the latex, increasing the risk of condom failure.

Pre-exposure prophylaxis (PrEP) is a daily medication that an HIV-negative person can take to lower their risk of contracting HIV. According to the CDC, daily use of PrEP can lower the risk of contracting HIV through sex by more than 90 percent.Trusted Source

Safer sex also involves keeping open lines of communication with your partner. Discuss the risks associated with condomless sex, and share your HIV status with your sexual partner. If a partner living with HIV is taking antiretroviral medication, once they’ve reached an undetectable viral load they aren’t capable of transmitting HIV. An HIV-negative partner should be tested for HIV and other sexually transmitted infections every six monthsTrusted Source.

Shared needles for drug use or tattoos can be a source of HIV transmission. Many communities offer needle exchange programs that provide clean needles to reduce the transmission of HIV and other infections such as hepatitis C. Make use of this resource as needed, and ask for help from a medical provider or social worker for drug misuse interventions.

When HIV first emerged, living with HIV was a death sentence that carried tremendous social stigma. Researchers have studied transmission extensively and developed treatments that allow many people who are infected to live long, productive lives and practically eliminate any risk of transmitting HIV during sex.

Today, improving HIV education and banishing the myths about HIV transmission are the best ways to end the social stigma still associated with living with HIV.

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