What is HIV?
HIV (Human Immunodeficiency Virus) is the virus that causes AIDS. This virus is passed from one person to another through blood-to-blood and sexual contact. In addition, infected pregnant women can pass HIV to their baby during pregnancy or delivery, as well as through breast-feeding. People with HIV have what is called HIV infection. Most of these people will develop AIDS as a result of their HIV infection. These body fluids have been proven to spread HIV:

  • blood
  • semen
  • vaginal fluid
  • breast milk
  • other body fluids containing blood

These are additional body fluids that may transmit the virus that health care workers may come into contact with:

  • cerebrospinal fluid surrounding the brain and the spinal cord
  • synovial fluid surrounding bone joints
  • amniotic fluid surrounding a fetus

What is AIDS? What causes AIDS?

AIDS stands for acquired immunodeficiency syndrome. An HIV-infected person receives a diagnosis of AIDS after developing one of the defined AIDS indicator illnesses. An HIV-positive person who has not had any serious illnesses also can receive an AIDS diagnosis on the basis of certain blood tests (CD4+ counts).

A positive HIV test result does not mean that a person has AIDS. A diagnosis of AIDS is made by a physician using certain clinical criteria (e.g., AIDS indicator illnesses).

Infection with HIV can weaken the immune system to the point that it has difficulty fighting off certain infections. These types of infections are known as “opportunistic” infections because they take the opportunity a weakened immune system gives to cause illness. Many of the infections that cause problems or may be life-threatening for people with AIDS are usually controlled by a healthy immune system. The immune system of a person with AIDS is weakened to the point that medical intervention may be necessary to prevent or treat serious illness.

Today there are medical treatments that can slow down the rate at which HIV weakens the immune system. There are other treatments that can prevent or cure some of the illnesses associated with AIDS. As with other diseases, early detection offers more options for treatment and preventative care.

How long does it take for HIV to cause AIDS?

Since 1992, scientists have estimated that about half the people with HIV develop AIDS within 10 years after becoming infected. This time varies greatly from person to person and can depend on many factors, including a person’s health status and their health-related behaviors.

Today there are medical treatments that can slow down the rate at which HIV weakens the immune system. There are other treatments that can prevent or cure some of the illnesses associated with AIDS, though the treatments do not cure AIDS itself. As with other diseases, early detection offers more options for treatment and preventative health care.

How is HIV passed from one person to another?

HIV transmission can occur when blood, semen (including pre-seminal fluid, or “pre-cum”), vaginal fluid, or breast milk from an infected person enters the body of an uninfected person.

HIV can enter the body through a vein (e.g. injection drug use), the anus or rectum, the vagina, the penis, the mouth, other mucous membranes (e.g., eyes or inside of the nose), or cuts and sores. Intact, healthy skin is an excellent barrier against HIV and other viruses and bacteria.

These are the most common ways that HIV is transmitted from one person to another:

  • By having sexual intercourse (anal, vaginal, or oral sex) with an HIV-infected person;
  • By sharing needles or injection equipment with an injection drug user who is infected with HIV;
  • From HIV-infected women to babies before or during birth, or through breast-feeding after birth.

HIV also can be transmitted through transfusions of infected blood or blood clotting factors. However, since 1985, all donated blood in the United States has been tested for HIV. Therefore, the risk of infection through transfusion of blood or blood products is very low.

Some health-care workers have become infected after being stuck with needles containing HIV-infected blood or, less frequently, after infected blood contact with the worker’s open cut or through splashes into the worker’s eyes or inside their nose. There has been only one instance of patients being infected by an HIV-infected health care worker. This involved HIV transmission from an infected dentist to six patients. The CDC has as yet been unable to establish how the transmission took place.

Can I get HIV from kissing on the cheek?

HIV is not casually transmitted, so kissing on the cheek is very safe. Even if the other person has the virus, your unbroken skin is a good barrier. No one has become infected from such ordinary social contact as dry kisses, hugs, and handshakes.

Can I get HIV from open-mouth kissing?

Open-mouth kissing is considered a very low-risk activity for the transmission of HIV. However, prolonged open-mouth kissing could damage the mouth or lips and allow HIV to pass from an infected person to a partner and then enter the body through cuts or sores in the mouth. Because of this possible risk, the CDC recommends against open-mouth kissing with an infected partner.

How effective are latex condoms in preventing HIV?

Studies have shown that latex condoms are highly effective in preventing HIV transmission when used consistently and correctly. These studies looked at uninfected people considered to be at very high risk of infection because they were involved in sexual relationships with HIV-infected people. The studies found that even with repeated sexual contact, 98-100 percent of those people who used latex condoms correctly and consistently did not become infected.

Is there a connection between HIV and other sexually transmitted diseases?

Yes. Having a sexually transmitted disease (STD) can increase a person’s risk of becoming infected with HIV, whether the STD causes open sores or breaks in the skin (e.g., syphilis, herpes, chancroid) or does not cause breaks in the skin (e.g., chlamydia, gonorrhea).

If the STD infection causes irritation of the skin, breaks or sores may make it easier for HIV to enter the body during sexual contact. Even when the STD causes no breaks or open sores, the infection can stimulate an immune response in the genital area that can make HIV transmission more likely.

In addition, if an HIV-infected person also is infected with another STD, that person is three to five times more likely than other HIV-infected persons to transmit HIV through sexual contact.

Not having (abstaining from) sexual intercourse is the most effective way to avoid STDs, including HIV. For those who choose to be sexually active, the following HIV prevention activities are highly effective:

  • Engaging in sex that does not involve vaginal, anal or oral sex;
  • Having intercourse with only one uninfected partner;
  • Using latex condoms every time you have sex.

How can people who use injection drugs reduce their risk of HIV infection?

The CDC recommends that people who inject drugs should be regularly counseled to:

  • Stop using and injecting drugs;
  • Enter and complete substance abuse treatment, including relapse prevention.

For injection drug users who cannot or will not stop injecting drugs, the following steps may be taken to reduce personal and public health risks:

  • Never reuse or “share” syringes, water, or drug preparation equipment.
  • Only use syringes obtained from a reliable source (such as pharmacies or needle exchange programs).
  • Use a new, sterile syringe to prepare and inject drugs.
  • If possible, use sterile water to prepare drugs; otherwise, use clean water from a reliable source (such as fresh tap water).
  • Use a new or disinfected container (“cooker”) and a new filter (“cotton”) to prepare drugs.
  • Clean the injection site prior to injection with a new alcohol swab.
  • Safely dispose of syringes after one use.

If new, sterile syringes and other drug preparation and injection equipment are not available, then previously used equipment should be boiled in water or disinfected with bleach before reuse.

Can I get HIV from getting a tattoo or through body piercing?

A risk of HIV transmission does exist if instruments contaminated with blood are either not sterilized or disinfected or are used inappropriately between clients. CDC recommends that instruments that are intended to penetrate the skin be used once, then disposed of or thoroughly cleaned and sterilized.

Personal service workers who do tattooing or body piercing should be educated about how HIV is transmitted and take precautions to prevent transmission of HIV and other blood-borne infections in their settings. If you are considering getting a tattoo or having your body pierced, ask staff at the establishment what procedures they use to prevent the spread of HIV and other blood-borne infections, such as the hepatitis B virus. You also may call the local health department to find out what sterilization procedures are in place in the local area for these types of establishments.

Should I be concerned about getting infected with HIV while playing sports?

There are not documented cases of HIV being transmitted during participation in sports. The very low risk of transmission during sports participation would involve sports with direct body contact in which bleeding might be expected to occur.

If someone is bleeding, their participation in the sport should be interrupted until the wound stops bleeding and is both antiseptically cleaned and securely bandaged. There is no risk of HIV transmission through sports activities where bleeding does not occur.

Can I get HIV from casual contact (shaking hands, hugging, using a toilet, drinking from the same glass, or sneezing and coughing of an infected person)?

No. HIV is not transmitted by day-to-day contact in the workplace, schools, or social settings. HIV is not transmitted through shaking hands, hugging, or a casual kiss. You cannot become infected from a toilet seat, a drinking fountain, a door knob, dishes, drinking glasses, food, or pets.

A small number of cases of transmission have been reported in which a person became infected with HIV as a result of contact with blood or other body secretions from an HIV-infected person in the household. Although contact with blood and other body substances can occur in households, transmission of HIV is rare in this setting. However, persons infected with HIV and persons providing home care for those who are HIV-infected should be fully educated and trained regarding appropriate infection control techniques.

Can I get infected with HIV from mosquitoes?

No. From the start of the HIV epidemic there has been concern about HIV transmission of the virus by biting and bloodsucking insects, such as mosquitoes. However, studies conducted by the CDC and elsewhere have shown no evidence of HIV transmission through mosquitoes or any other insect.