How is HIV Transmitted?
How is HIV Transmitted?
HIV can be transmitted from an infected person to another through:
- Blood (including menstrual blood)
- Vaginal secretions
- Breast milk
In the United States, HIV is spread mainly by having sex or sharing injection drug equipment such as needles with someone who has HIV. Only certain fluids - blood, semen (cum), pre-seminal fluid (pre-cum), rectal fluids, vaginal fluids, and breast milk - from an HIV-infected person can transmit HIV.
Blood contains the highest concentration of the virus, followed by semen, followed by vaginal fluids, followed by breast milk.
* Activities That Allow HIV Transmission
- Unprotected sexual contact
- Direct blood contact, including injection drug needles, blood transfusions, accidents in health care settings or certain blood products
- Mother to baby (before or during birth, or through breast milk)
- Sexual intercourse (vaginal and anal): In the genitals and the rectum, HIV may infect the mucous membranes directly or enter through cuts and sores caused during intercourse (many of which would be unnoticed). Vaginal and anal intercourse is a high-risk practice.
- Oral sex (mouth-penis, mouth-vagina): The mouth is an inhospitable environment for HIV (in semen, vaginal fluid or blood), meaning the risk of HIV transmission through the throat, gums, and oral membranes is lower than through vaginal or anal membranes. There are however, documented cases where HIV was transmitted orally, so we can’t say that getting HIV-infected semen, vaginal fluid or blood in the mouth is without risk. However, oral sex is considered a low risk practice.
- Sharing injection needles: An injection needle can pass blood directly from one person’s bloodstream to another. It is a very efficient way to transmit a blood-borne virus. Sharing needles is considered a high-risk practice.
- Mother to Child: It is possible for an HIV-infected mother to pass the virus directly before or during birth, or through breast milk. Breast milk contains HIV, and while small amounts of breast milk do not pose significant threat of infection to adults, it is a viable means of transmission to infants.
The following “bodily fluids” are NOT infectious:
Can I get HIV from oral sex?
There is considerable debate within the HIV/AIDS prevention community regarding the risk of transmission of HIV through oral sex. What is currently known is that there is some risk associated with performing oral sex without protection; (there have been a few documented cases of HIV transmission through oral sex). While no one knows exactly what that risk is, cumulative evidence indicates that the risk is less than that of unprotected anal or vaginal sex. The risk from receiving oral sex, for both a man and a woman, is considered to be very low.
Currently, risk reduction options when performing oral sex on a man (fellatio) include the use of latex condoms, but also include withdrawal before ejaculation without a condom (avoiding semen in the mouth) and/or refraining from this activity when cuts or sores are present in the mouth.
What if I test HIV positive?
- What if I test HIV positive?
- Can I get HIV from kissing?
- How is HIV Transmitted?
- Can I get HIV from oral sex?
- Can I get HIV from casual contact?
- Can a woman give HIV to a man during vaginal intercourse?
- How effective are latex condoms in preventing HIV?
- How long after a possible exposure should I be tested for HIV?
When performing oral sex on a woman (cunnilingus), moisture barriers such as a dam (sheet of latex), a cut-open and flattened condom, or household plastic wrap can reduce the risk of exposure to vaginal secretions and/or blood.
Casual contact through closed-mouth or “social” kissing is not a risk for transmission of HIV. Because of the potential for contact with blood during “French” or open-mouth, wet kissing, CDC recommends against engaging in this activity with a person known to be infected. However, the risk of acquiring HIV during open-mouth kissing is believed to be very low. CDC has investigated only one case of HIV infection that may be attributed to contact with blood during open-mouth kissing. In this case both partners had extensive dental problems including gingivitis (inflammation of the gums). It is likely that there was blood present in both partners’ mouths making direct blood to blood contact a possibility.
Can I get HIV from casual contact (shaking hands, hugging, using a toilet, drinking from the same glass, or the sneezing and coughing of an infected person)?
No. HIV is not transmitted by day to day contact in the home, 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 doorknob, dishes, drinking glasses, food, or pets.
HIV is a fragile virus that does not live long outside the body. HIV is not an airborne or food borne virus. HIV is present in the blood, semen or vaginal secretions of an infected person and can be transmitted through unprotected vaginal, oral or anal sex or through sharing injection drug needles.
Can a woman give HIV to a man during vaginal intercourse?
Yes. If the woman is infected, HIV is present in vaginal and cervical secretions (the wetness in a woman’s vagina) and can enter the penis through the urethra (the hole at the tip) or through cuts or abrasions on the skin of the penis. The presence of other STDs can increase the risk of transmission. The correct and consistent use of a latex condom or female condom can reduce the risk of transmitting HIV during vaginal intercourse. For more information, call the CDC National AIDS Hotline at 1-800-342-2437 (English), 1-800-344-7432 (Spanish), or 1-800-243-7889 (TTY).
How effective are latex condoms in preventing HIV?
Several studies have demonstrated that latex condoms are highly effective in preventing HIV transmission when used correctly and consistently. 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 persons. The studies found that even with repeated sexual contact, 98-100% of those people who used latex condoms consistently and correctly remained uninfected. For more on these studies, including free written information, call the CDC National AIDS Hotline at 1-800-342-2437 (English), 1-800-344-7432 (Spanish), or 1-800-243-7889 (TTY).
HIV Infection and AIDS - the Third Stage
AIDS (acquired immune deficiency syndrome) is the advanced stage of HIV infection. When the CD4 T-cell number drops below 200, people are diagnosed with AIDS.
Someone infected with HIV can also be diagnosed with AIDS if they have an “AIDS defining illness” such as Kaposi’s sarcoma (a form of skin cancer) or pneumocystis pneumonia (a lung disease).
Fortunately, combination medications used to treat HIV - a “cocktail” – can help rebuild the immune system. These drugs can be expensive and pose challenges with side effects, but it is critical to not stop taking them without talking to your doctor. It is also important not to take part of the medications without taking the others. People with low CD4 T-cells may also receive drugs to prevent opportunistic infections. These preventative medications should be taken until the CD4 count has improved.
Some people don’t know they were infected with HIV, and only discover their HIV infection after experiencing some of these HIV-related symptoms:
Being tired all of the time
Swollen lymph nodes in the neck or groin
Fever lasting for more than 10 days
Unexplained weight loss
Purplish spots on the skin that don’t go away
Shortness of breath
Severe, long-lasting diarrhea
Yeast infections in the mouth, throat, or vagina
Easy bruising or unexplained bleeding
If you test positive, the sooner you take steps to protect your health, the better. Early medical treatment, a healthy lifestyle and a positive attitude can help you stay well. Prompt medical care may delay the onset of AIDS and prevent some life-threatening conditions. It is important to know that a positive HIV test should always be confirmed, to be sure that it is a true positive. If your test result is positive, there are a number of important steps you can take immediately to protect your health:
- See a doctor, even if you don’t feel sick. Try to find a doctor who has experience treating HIV. There are now many new drugs to treat HIV infection. There are important tests, immunizations and drug treatments that can help you maintain good health. It is never too early to start thinking about treatment possibilities.
- Have a tuberculosis (TB) test done. You may be infected with TB and not know it. Undetected TB can cause serious illness. TB can be treated successfully if detected early.
- Recreational drugs, alcoholic beverages and smoking can weaken your immune system. There are programs available to help you stop.
- Consider joining a support group for people with HIV infection or finding out about other resources available in your area, such as HIV/AIDS-knowledgeable counselors for one on one therapy. There are also many newsletters available for people living with HIV and AIDS.
- There is much you can do to stay healthy. Learning as much as you can is a step in the right direction. Local and/or national resources may be available. Many HIV/AIDS organizations provide services free or on a sliding scale, based on ability to pay.
- Call the CDC National AIDS Hotline for more information and referrals at 1-800-342-2437 (English), 1-800-344-7432, (Spanish), or 1-800-243-7889 (TTY).
How long after a possible exposure should I be tested for HIV?
The time it takes for a person who has been infected with HIV to seroconvert (test positive) for HIV antibodies is commonly called the “Window Period.”
The California Office of AIDS, published in 1998, says about the window period: “When a person is infected with the HIV virus, statistics show that 95-97% (perhaps higher) of all infected individuals develop antibodies within 12 weeks (3-months).”
The National CDC has said that in some rare cases, it may take up to six months for one to seroconvert (test positive). At this point the results would be 99.9% accurate.
* What does this mean for you?
The three-month window period is normal for approximately 95% of the population. If you feel any anxiety about relying on the 3-month result, by all means you should have another test at 6 months.
When do you know for sure that you are not infected with HIV?
The tests commonly used to determine HIV infection actually look for antibodies produced by the body to fight HIV. According to the Centers for Disease Control and Prevention (CDC), most people will develop detectable antibodies within 3 months after infection. In rare cases, it can take up to six months. Therefore, the CDC recommends testing at 6 months after the last possible exposure. (unprotected vaginal, anal or oral sex or sharing injecting drug needles). It would be extremely rare to take longer than six months to develop detectable antibodies. It is important, during the six months between exposure and the 6-month test, to protect yourself and others from further exposures to HIV. The CDC National AIDS Hotline can provide more information and referrals to testing sites in your area.
Source: Your Health Encyclopedia, 4-rd Edition, 2002