The STI Files: Human Immunodeficiency Virus (HIV)

Stat: About 1 out⁠ of every 250 people in the United States alone carries the HIV⁠ virus according to current estimates, and women are the group hardest hit globally by HIV and AIDS⁠ .

What is it exactly? HIV is a virus that destroys the immune system, reducing the body's ability to fight disease and infection⁠ , even very common infections like flus and colds. HIV usually progresses to AIDS. This makes HIV the most dangerous sexually transmitted infection today. It is the fifth leading cause of death for the young under 40 in the United States. At this time, no one has been cured of HIV or AIDS.

About how many people have it? About 40,000 people in the United States become infected with HIV every year. Approximately 33 million people worldwide are HIV-positive.

How is it spread? Through body fluids (namely blood, semen⁠ , penile and vaginal secretions and breast⁠ milk -- HIV can be present in saliva, but kissing⁠ and other general exposures to saliva are not known to present risks of transmission), through anal and vaginal intercourse⁠ or oral sex⁠ , shared needles used for injecting IV drugs or accidental pricks with infected needles, blood transfusions, childbirth or breastfeeding.

What are its symptoms? Initial or acute infection may have symptoms that resemble mononucleosis or the flu within 2 to 4 weeks of exposure, but in many people, HIV infection does not show any symptoms for extended periods of time, and for some, is asymptomatic for as long as 20 years, though that is quite rare.

For those who experience symptoms, they may include: sore throat or mouth sores, aching or stiff muscles or joints, headaches, diarrhea, swollen glands, fevers, persistent fatigue or tiredness, rashes or excema, yeast infections, rapid weight loss or chronic PID⁠ .

How is it diagnosed? By a blood test which screens for antibodies. Because it can take up to three months or more for the antibodies to appear, a negative test should always be repeated, and an annual or semi-annual HIV screening is advised.

Is it treatable? Yes, through an intensive combination of antiretroviral drugs and consistent health care. The goal of treatment is to try and protect the immune system from further damage, and to delay the progression to AIDS for as long as possible.

Is it curable? There is currently no cure for HIV, only treatment for managing the existing infection.

Can it affect fertility⁠ ? It cannot affect fertility, but is very commonly transmitted from mother to child during pregnancy⁠ or childbirth, or through breastfeeding.

Can it cause death? Any severe compromise of the immune system can cause death, and if HIV infection becomes acute or progresses to become AIDS, it is fatal. Most HIV infections do progress to AIDS.

How can we protect against it? By ALWAYS using condoms for vaginal intercourse, anal intercourse⁠ or oral sex. HIV can also be prevented by decreasing your number of sexual⁠ partners, by avoiding high-risk sexual practices like anal sex⁠ or oral-anal sex or unprotected vaginal or oral sex, by avoiding sex⁠ with those who use intravenous drugs and by not participating in IV drug use yourself, by not allowing urine to come into contact with the mouth, anus⁠ , eyes, or any open cuts or sores, and by getting annual or semi-annual HIV screenings, and insisting your partners do likewise.

There is also "morning-after" treatment for those who have been exposed to the HIV virus, called Post-Exposure Prophylaxis, PEP⁠ (or nPEP). Studies show PEP reduces the risk of HIV infection at least 90% and up to 99%. PEP isn't available everywhere, or to just everyone: it's primarily used for health-care workers, but is also sometimes now used for pregnant women or rape⁠ victims known or strongly suspected to have been exposed to the virus. Ideally, it should be used within just a couple hours after exposure, and is no longer suggested once 72 hours have passed.

As well, PrEP⁠ (pre-exposure prophylaxis) is a daily pill that can reduce the risk of HIV by as much as 99%, and is advised for those at high risk of contracting HIV, like those with HIV-positive partners. It should not be considered a replacement for safer sex⁠ practices, but ideally, as an addition to them.  For more detailed information about PrEP, talk with your healthcare provider⁠ or have a look at our guide to PEP and PrEP.

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