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Protect Others

If you are living with HIV, it’s important to make choices that keep you healthy and protect others.

How Is HIV Transmitted?

Understanding how HIV is transmitted will help you take steps to protect yourself and others. Someone who has HIV can transmit the virus in the following ways:

Less commonly, HIV may be spread by:

What Steps Can I Take To Protect My Partner(s)?

Talk about your HIV status with all of your sexual partners and take steps to protect your health and your partners' health.

The following actions can reduce your risk of transmitting HIV:

You should also encourage your partners who are HIV-negative to get tested for HIV at least once a year so they are sure about their HIV status and can take action to keep them healthy. To find an HIV testing site near them, they can call 1-800-CDC-INFO (232-4636), visit CDC's testing site locator, text their ZIP code to KNOW IT (566948), or use a home HIV testing kit.

You can also view stories and testimonials of how people living with HIV are protecting their partners on this website.

What Medicines Can Prevent My Partner(s) From Becoming Infected With HIV?

Pre-exposure prophylaxis (PrEP): “PrEP” stands for Pre-Exposure Prophylaxis. The word “prophylaxis” means to prevent or control the spread of an infection or disease. The goal of PrEP is to prevent HIV infection from taking hold if your partner is exposed to the virus. This is done by taking one pill every day. These are some of the same medicines used to keep the virus under control in people who are already living with HIV.

With 50,000 new HIV infections each year in the United States, and no cure or vaccine available, prevention is key. When taken every day, PrEP can provide a high level of protection against HIV. PrEP is even more effective when it is combined with condoms and other prevention tools.

CDC recommends that PrEP be considered for people who are HIV-negative and at substantial risk for HIV.

For sexual transmission, this includes anyone who is in an ongoing relationship with a partner who is living with HIV.

It also includes anyone who (1) is not in a mutually monogamous* relationship with a partner who recently tested HIV-negative, and (2) is a

* Mutually monogamous means that you and your partner only have sex with each other and do not have sex outside the relationship.

For heterosexual couples where one partner has HIV and the other does not, PrEP is one of several options to protect the uninfected partner during conception and pregnancy.

For people who inject drugs, this includes those who have injected illicit drugs in the past 6 months and who have shared injection equipment or been in drug treatment for injection drug use in the past 6 months.

People who use PrEP must be able to take the drug every day and to return to their health care provider every 3 months for a repeat HIV test, prescription refills, and follow-up.

In several studies of PrEP, the risk of getting HIV infection was much lower—up to 92% lower—for those who took the medicines consistently than for those who didn’t take the medicines.

See CDC’s PrEP web page for a brief description of these studies.

Learn more about PrEP by reading CDC’s PrEP 101 factsheet.

Post-exposure prophylaxis (PEP): PEP stands for Post-exposure Prophylaxis. It involves your partner taking antiretroviral medicines as soon as possible, but no more than 72 hours (3 days) after they may have been exposed to HIV, to try to reduce the chance of becoming HIV-positive. These medicines keep HIV from making copies of itself and spreading through their body. Two to three drugs are usually prescribed, and they must be taken for 28 days. PEP is not always effective; it does not guarantee that someone exposed to HIV will not become infected with HIV.

PEP is used for anyone who may have been exposed to HIV very recently during a single event (like unprotected sex, needle-sharing injection drug use, or sexual assault). It is not the right choice for people who may be exposed to HIV frequently. A health care provider will consider whether PEP is right for your partner based on the risk of their exposure.

Keep in mind that PEP should only be used in situations right after a potential HIV exposure. It is not a substitute for regular use of other proven HIV prevention methods, such as pre-exposure prophylaxis (PrEP), correct and consistent condom use, or use of sterile injection drug works.

If your partner is prescribed PEP, they will be asked to return for HIV testing at 4 to 6 weeks, 3 months, and 6 months after the potential exposure to HIV.

PEP must begin within 72 hours of exposure, before the virus has time to make too many copies of itself in the body.

Starting PEP as soon as possible after a potential HIV exposure is important: research has shown that PEP has little or no effect in preventing HIV infection if it is started more than 72 hours after HIV exposure. HIV makes copies of itself once it enters the body, and it takes about 3 days for it to spread through the body. When HIV is only in a few cells where it entered the body, it can sometimes be stopped by PEP. When HIV is in many cells in many places in the body, PEP will not work.

More information about PEP is available from CDC’s PEP 101.