Overview
AIDS is a chronic, life-threatening condition caused by the human immunodeficiency virus (HIV). By damaging or destroying the cells of your immune system, HIV interferes with your body's ability to effectively fight off viruses, bacteria and fungi that cause disease. This makes you more susceptible to opportunistic infections your body would normally resist, such as pneumonia and meningitis, and to certain types of cancers.
The virus and the infection itself are known as HIV. The term AIDS (acquired immunodeficiency syndrome) is used to mean the later stages of HIV infection. But both the terms HIV and AIDS refer to the same disease.
HIV is most commonly spread by sexual contact with an infected partner. It can also spread through infected blood and shared needles or syringes contaminated with the virus. Untreated women with HIV also can pass the infection to their babies during pregnancy, delivery or through their breast milk.
In the two decades since the first reports of the disease, AIDS has become a global epidemic. Worldwide, an estimated 40 million people are living with HIV, including an estimated 2.5 million children younger than 15. According to the United Nations Program on HIV/AIDS (UNAIDS) and the World Health Organization (WHO), 5 million people were newly infected with HIV in 2003 and 3 million people died from AIDS.
In sub-Saharan Africa, the area of the world most severely impacted by AIDS, 3 million new infections occurred in 2003, and there were 2.3 million AIDS deaths. The AIDS epidemic is also growing fast in China, India, Indonesia, Russia, Eastern Europe and Central Asia.
Currently, an estimated 850,000 to 950,000 Americans are living with HIV/AIDS. This is partly the result of improved treatments. Since 1995 the number of medications available to treat AIDS has greatly increased, and powerful combinations of newer antiretroviral drugs have helped reduce serious complications of the disease and prolong life. But the emergence of drug-resistant forms of HIV threatens the positive news about treatment.
Of equal concern is a growing public complacency about AIDS. Nearly a third of the people living with HIV don't know they're infected and so are more likely to spread the disease. And reports from several cities in both the United States and Europe show increased high-risk behavior among young gay men. Drug use is also fueling the spread of HIV here and abroad. These facts have led experts to warn that the 20-year-old epidemic is still in its early stages.
Signs and symptoms
The symptoms of HIV and AIDS vary, depending on the phase of infection. When first infected with HIV, you may have no symptoms at all, although it's more common to develop a brief flu-like illness 2 to 6 weeks after becoming infected. But because the symptoms of an initial infection — which may include fever, headache, sore throat, swollen lymph glands and rash — are similar to those of other diseases, you might not realize you've been infected with HIV.
Even if you don't have symptoms, you're still able to transmit the virus to others. Once the virus enters your body, your own immune system also comes under attack. The virus multiplies in your lymph nodes and slowly begins to destroy your helper T cells (CD4 lymphocytes) — the white blood cells that coordinate your entire immune system.
You may remain symptom-free for 8 or 9 years. But the virus continues to multiply and destroy immune cells. Tests are likely to show a sharp decline in the number of these cells in your blood. Eventually, you may develop mild infections or chronic symptoms such as:
Swollen lymph nodes — often one of the first signs of HIV infection
Diarrhea
Weight loss
Fever
Cough and shortness of breath
During the last phase of HIV — which occurs approximately 10 to 11 years
after the initial infection — more serious symptoms may begin to appear,
and the infection may then meet the official definition of AIDS. In 1993 the
Centers for Disease Control and Prevention (CDC) redefined AIDS to mean the
presence of HIV infection as shown by a positive HIV-antibody test plus at least
one of the following:
The development of an opportunistic infection — an infection that occurs
when your immune system is impaired — such as Pneumocystis carinii pneumonia
(PCP)
A CD4 lymphocyte count of 200 or less — a normal count ranges from 600
to 1,000
By the time AIDS develops, your immune system has been severely damaged, making
you susceptible to opportunistic infections. The signs and symptoms of some
of these infections may include:
Soaking night sweats
Shaking chills or fever higher than 100 F for several weeks
Dry cough and shortness of breath
Chronic diarrhea
Persistent white spots or unusual lesions on your tongue or in your mouth
Headaches
Blurred and distorted vision
Weight loss
You may also begin to experience signs and symptoms of later-stage HIV infection
itself, such as:
Persistent, unexplained fatigue
Soaking night sweats
Shaking chills or fever higher than 100 F for several weeks
Swelling of lymph nodes for more than 3 months
Chronic diarrhea
Persistent headaches
If you're infected with HIV, you're also more likely to develop certain cancers,
especially Kaposi's sarcoma, cervical cancer and lymphoma.
Symptoms of HIV in children
Children who are HIV-positive often fail to gain weight or grow normally. As
the disease progresses, they may have difficulty walking or delayed mental development
and may develop cerebral palsy. Children are also susceptible to the same opportunistic
infections adults are and may have severe forms of common childhood illnesses
such as ear infections (otitis media), pneumonia and tonsillitis.
Causes
Normally, white blood cells and antibodies attack and destroy foreign organisms that enter your body. This response is coordinated by white blood cells known as CD4 lymphocytes. Unfortunately, CD4 lymphocytes are also the main targets of HIV, which attaches to the cells and then enters them. Once inside, the virus inserts its own genetic material into the CD4 lymphocytes and uses them to make copies of itself.
When the new copies of the virus break out of the host cells and enter your bloodstream, they search for other cells to attack. In the meantime, the old host cells die. The cycle repeats itself again and again. In the process, more than 10 billion new HIV particles are produced every day. To counter this huge virus production, your immune system turns out as many as 2 billion new CD4 cells daily.
Eventually, the virus wins this race. The number of CD4 cells in your body progressively decreases, and you develop severe immune deficiency, which means your body can't effectively fight off viruses and bacteria that cause disease.
How HIV is transmitted
You can become infected with HIV in several ways, including:
Sexual transmission. You may become infected if you have vaginal, anal or oral
sex with an infected partner whose blood, semen or vaginal secretions enter
your body. You can also become infected from shared sexual devices if they're
not washed or covered with a condom. The virus is present in the semen or vaginal
secretions of someone who's infected and enters your body through small tears
that can develop in your rectum or vagina during sexual activity. If you already
have another sexually transmitted disease, you're at much greater risk of contracting
HIV. Contrary to what researchers once believed, women who use the spermicide
nonoxynol-9 also may be at increased risk. This spermicide irritates the lining
of the vagina and may cause tears that allow the virus into your body.
Transmission through infected blood. In some cases the virus may be transmitted
through blood and blood products — including whole blood, packed red cells,
fresh-frozen plasma and platelets — you receive in blood transfusions.
In 1985 American hospitals and blood banks began screening the blood supply
for HIV antibodies. This blood testing, along with improvements in donor screening
and recruitment practices, has substantially reduced the risk of acquiring HIV
through a transfusion. Currently, the chance of transfusion-associated transmission
in the United States is about 1 in every 450,000 to 1 in every 600,000 transfusions.
Transmission through needle sharing. HIV is easily transmitted through needles
and syringes contaminated with infected blood. That's why sharing intravenous
drug paraphernalia puts you at high risk of HIV and of other infectious diseases
such as hepatitis. Your risk is increased if you inject drugs frequently or
also engage in high-risk sexual behavior. Although avoiding the use of injected
drugs is the most reliable way to prevent infection, this may not be an option
for you. If so, one way to reduce your risk is to use household bleach to sterilize
injection paraphernalia. Another option is to participate in a needle exchange
program in your community. These programs allow you to exchange used needles
and syringes for sterile equipment. Finally, consider seeking counseling or
treatment for your drug use.
Transmission through accidental needle sticks. Transmission of the virus between
HIV-infected patients and health care workers through needle sticks is low.
The average risk is approximately 3 in 1,000.
Transmission from mother to child. Between one-quarter and one-third of untreated
pregnant women infected with HIV pass the infection to their babies. But if
women receive treatment for their HIV infection during pregnancy, the risk to
their babies decreases as much as two-thirds. When treatment is combined with
Caesarean section, the infection rate may drop even further.
Other methods of transmission. In rare cases the virus may be transmitted through
organ or tissue transplants or unsterilized dental or surgical equipment.
Ways HIV is not transmitted
To become infected with HIV, infected blood, semen or vaginal secretions must
enter your body. You can't become infected through ordinary contact — hugging,
dancing or shaking hands — with someone who has HIV or AIDS. You also can't
be infected in any of the following ways:
Coming into contact with the sweat or tears of someone with HIV or AIDS.
Sharing food, utensils, towels or bedding, a swimming pool, telephone or toilet
seat with someone who has the virus.
Being bitten by bedbugs or mosquitoes.
Kissing someone who is HIV-positive or who has AIDS. There's no evidence that
the virus is transmitted through kissing. Although HIV is sometimes found in
the saliva of people with the virus, it occurs in low concentrations. In addition,
natural inhibitory substances in saliva help prevent transmission of the virus.
Donating blood.
Risk factors
HIV crosses all cultures, national borders and religions. Anyone, of any age, race, sex or sexual orientation can be infected, but you're at greatest risk of HIV/AIDS if you:
Have unprotected sex with multiple partners. You're at risk whether you're
heterosexual, homosexual or bisexual. Unprotected sex means having sex without
using a new latex or polyurethane condom every time.
Have unprotected sex with someone who is HIV-positive.
Have another sexually transmitted disease, such as syphilis, herpes, chlamydia,
gonorrhea or bacterial vaginosis.
Share needles during intravenous drug use.
Are a person with hemophilia who received blood products between 1977 and April
1985 — the date standard testing for HIV began.
Received a blood transfusion or blood products before 1985.
Newborns or nursing infants whose mothers have tested positive for HIV also
are at high risk.
Treatment
When HIV was first identified in the early 1980s, there were no drugs to treat the virus and few treatments for the opportunistic infections associated with it. Since then, a number of medications have been developed to treat both HIV/AIDS and opportunistic infections. For many people, including children, newer treatments have both extended and improved the quality of life. But none of these drugs can cure HIV/AIDS, many have side effects that can be quite severe, and treatment is often expensive.
Treatment guidelines
A panel of leading AIDS specialists has developed recommendations for the use
of antiretroviral medications in people with HIV. These recommendations are
based on the best information available at the time they were developed. The
HIV/AIDS Treatment Information Service has a program in place to regularly refine
and update the recommendations as knowledge about HIV infection evolves.
According to current guidelines, treatment should focus on achieving the maximum
suppression of symptoms for as long as possible. This aggressive approach is
known as highly active antiretroviral therapy (HAART). The aim of HAART is to
reduce the amount of virus in your blood to very low, or even nondetectable,
levels, although this doesn't mean the virus is gone. This is usually accomplished
with a combination of three or more drugs.
But the treatment guidelines also emphasize the importance of quality of life. Thus the goal of AIDS treatment is to find the strongest possible regimen that is also simple and has the fewest side effects. If you have HIV/AIDS, it's important that you take an active role in every treatment decision. You and your doctor should discuss the risks and benefits of all therapies so that you can make an informed decision about what will likely be a complex and long-term treatment.
Prevention
There's no vaccine to prevent HIV infection and no cure for AIDS. But it's possible to protect yourself and others from infection. That means educating yourself about HIV and avoiding any behavior that allows HIV-infected fluids — blood, semen, vaginal secretions and breast milk — into your body.
If you're HIV-negative
The following measures can help keep you from being infected with HIV:
Educate yourself and others. Make sure you understand what HIV is and how the
virus is transmitted. Just as important, teach your children about HIV.
Know the HIV status of any sexual partner. Don't engage in unprotected sex unless
you're absolutely certain your partner isn't infected with HIV.
Use a new latex or polyurethane condom every time you have sex. If you don't
know the HIV status of your partner, use a new latex condom every time you have
anal or vaginal sex. If you're allergic to latex, use a plastic (polyurethane)
condom. Avoid lambskin condoms — they do not protect you from HIV. If you
don't have a male condom, use a female condom. Use only water-based lubricants,
not petroleum jelly, cold cream or oils. Oil-based lubricants can weaken condoms
and cause them to break. During oral sex use a condom, dental dam — a piece
of medical-grade latex —or plastic wrap. Remember that although condoms
can reduce your risk of contracting HIV, they don't eliminate the risk entirely.
Condoms can break or develop small tears, and they may not always be used properly.
Use a clean needle. If you use a needle to inject drugs, make sure it's sterile,
and don't share it. Take advantage of needle exchange programs in your community
and consider seeking help for your drug use.
Be cautious about blood products in certain countries. Although the blood supply
in the United States is now well screened, this isn't always the case in other
countries. If an emergency requires that you receive blood or blood products
in another country, get tested for HIV as soon as you return home.
Get regular screening tests. If you're a woman, have a yearly Pap test. Men
and women who engage in anal sex should also have regular tests for anal cancer.
Don't become complacent. Because potent antiretroviral medications have reduced
the number of AIDS deaths in the United States, you may think that HIV infection
is no longer a problem. But HIV/AIDS is still a terminal illness for which there
is no vaccine and no cure. Right now, the only way to stay healthy is to protect
yourself and others from infection.
If you're HIV-positive
If you've received a diagnosis of HIV/AIDS, the following guidelines can help
protect others:
Follow safer sex practices. The only foolproof way to protect your sexual partner
or partners from HIV infection is to avoid practices that expose them to blood,
semen or vaginal secretions. Barring that, carefully follow guidelines for safer
sex, including using a new latex condom every time you have vaginal or anal
sex and using a dental dam, condom or piece of plastic wrap during oral sex.
If you use sexual devices, don't share them.
Tell your sexual partner(s) you have HIV. It's important to tell anyone with
whom you've had sex that you're HIV-positive. Your partners need to be tested
and to receive medical care if they have the virus. They also need to know their
HIV status so they don't infect others.
If your partner is pregnant, tell her you have HIV. Even if you're not the father,
be sure to tell any pregnant woman with whom you've had sex that you're HIV-positive.
She needs to receive treatment to protect her own health and that of her baby.
Tell others who need to know. Although only you can decide whether to tell friends
and family about your illness, you do need to inform your health care providers
of your HIV status. This is not just to protect them, but also to ensure that
you get the best possible medical care.
Don't share needles or syringes. If you use intravenous drugs, never share your
needles and syringes with anyone else.
Don't donate blood or organs. The virus will spread to other people.
Don't share razor blades or toothbrushes. These items may carry traces of HIV-infected
blood.
If you're pregnant, get medical care right away. If you're HIV-positive, you
may pass the infection to your baby. But if you receive treatment during pregnancy,
you can cut your baby's risk by as much as two-thirds. Having your baby by Caesarean
section cuts the risk even further.
Self-care
Although it's important to receive medical treatment for HIV/AIDS, it's also essential to take an active role in your own care. The following suggestions may help you stay healthy longer:
Make sure your doctor knows how to treat HIV. Find someone who understands
all the ramifications of the disease. You'll also want a doctor who is willing
to work with you and who makes you feel comfortable and respected.
Follow your doctor's instructions. Keep all of your appointments, and take your
medications exactly as directed. This is often challenging because you may have
to take a number of medications throughout the day. But it's essential to follow
your schedule as closely as possible. If you get sick from your medication,
call your doctor. Don't stop taking your medication or change the dosage on
your own.
Get immunizations. These may prevent infections such as pneumonia and the flu.
Don't smoke or use illegal drugs. These weaken your body even more.
Eat the healthiest diet you can. Emphasize fresh fruits and vegetables, whole
grains and lean protein. Healthy foods help keep you strong, give you more energy
and support your immune system. Unfortunately, you may not always feel like
eating when you have HIV. But good nutrition is tremendously important. A registered
dietitian can be especially helpful if you have diarrhea, weight loss or trouble
eating. Also, because your nutritional needs are extremely high and you may
not digest food well, talk to your doctor about vitamin and mineral supplements.
Avoid foods that may put you at risk of infection. These include unpasteurized
dairy products, raw eggs and raw seafood such as oysters, sushi or sashimi.
Cook meat until it's well-done or until there's no trace of pink color.
Drink pure water. The Department of Health and Human Services recommends that
you boil tap water or use bottled or filtered water for drinking. If you buy
a water filter, look for one that uses reverse osmosis as part of the purification
process.
Get regular exercise. Exercise helps increase your strength and energy levels
and can help battle the depression that's often a part of dealing with HIV/AIDS.
Get enough sleep. Rest when you need to.
Take care with companion animals. Some animals may carry parasites that can
cause infections in people who are HIV-positive. But that doesn't mean you should
give up your companion animal. Animals are a great source of comfort. You can
protect yourself by having someone else clean your cat's litter box or pick
up after your dog. If you must do these chores yourself, wear latex gloves and
wash your hands immediately afterward. Don't feed your pets raw meat, and make
sure they have all of their shots. Always wash your hands thoroughly with soap
and water after petting or playing with your animals.
Find ways to relax. This might mean anything from yoga or meditation to walking,
reading, playing chess or computer games, or listening to music.
Keep your hands clean. Wash your hands thoroughly with soap and water after
using the restroom, before eating or preparing food and after spending time
in public places. You might find it helpful to carry a waterless alcohol gel
with you for times when it's not convenient to use soap and water.