WHAT IS TMP/SMX? WHY DO PEOPLE WITH HIV TAKE TMP/SMX? WHAT ABOUT DRUG RESISTANCE? HOW IS TMP/SMX TAKEN? WHAT ARE THE SIDE EFFECTS? HOW DOES TMP/SMX REACT WITH OTHER DRUGS? WHAT IS TMP/SMX? TMP/SMX is combination of two antibiotic drugs: trimethoprim and sulfamethoxazole. It is also known as cotrimoxazole. It is sold as Bactrim® (manufactured by Roche) or Septra® (by Monarch Pharmaceuticals). TMP/SMX is sold under many other names in different parts of the world. Antibiotics fight infections caused by bacteria. TMP/SMX is also used to fight some infections caused by protozoa, and some opportunistic infections in people with HIV. WHY DO PEOPLE WITH HIV TAKE TMP/SMX? TMP/SMX is used for many bacterial infections. It is effective and inexpensive. Unfortunately, up to one third of the people who take it get an allergic reaction Many germs live in our bodies or are common in our surroundings. A healthy immune system can fight them off or keep them under control. However, HIV infection can weaken the immune system. Infections that take advantage of weakened immune defenses are called "opportunistic infections." People with advanced HIV disease can get opportunistic infections. See Fact Sheet 500 for more information on opportunistic infections. One opportunistic infection in people with HIV is PCP. This stands for pneumocystis pneumonia, which affects the lungs. See Fact Sheet 515 for more information on PCP. People who have a CD4 cell count of less than 200 may develop PCP. TMP/SMX is the first choice to treat or prevent PCP. If your CD4 cell count is below 200, ask your health care provider if you should be taking TMP/SMX or another drug to prevent PCP. Another opportunistic infection is toxoplasmosis (toxo), which affects the brain. See Fact Sheet 517 for more information on toxo. People who have a CD4 cell count of less than 100 may develop toxo. TMP/SMX is sometimes used to treat or prevent cases of toxo. Some people are allergic to TMP/SMX. Be sure to tell your health care provider if you are allergic to sulfa drugs or antibiotics. People who are anemic should not use TMP/SMX. Taking TMP/SMX during pregnancy may increase the risk of birth defects. Women who are pregnant or breastfeeding should avoid taking it if possible. Also let your health care provider know if you have liver disease, kidney disease, or a shortage of the enzyme glucose-6-phosphate dehydrogenase (G6PD). WHAT ABOUT DRUG RESISTANCE? Whenever you take medication, be sure to take all of the prescribed doses. Many people stop if they feel better. This is not a good idea. If the drug doesn’t kill all of the germs, they might change (mutate) so that they can survive even when you are taking medications. When this happens, the drug will stop working. This is called "developing resistance" to the drug. For example, if you are taking TMP/SMX to fight PCP and you miss too many doses, the PCP in your body could develop resistance to TMP/SMX. Then you would have to take a different drug or combination of drugs to fight it. HOW IS TMP/SMX TAKEN? TMP/SMX is available in tablets that contain 80 milligrams (mg) of trimethoprim and 400 mg of sulfamethoxazole. There is also a "double strength" tablet with 160 mg of trimethoprim and 800 mg of sulfamethoxazole. The dose you take depends on the type of infection you are trying to treat or prevent. The treatment continues as long as your CD4 cell count is low enough for you to develop toxo or PCP. TMP/SMX is generally taken with food, but the single-strength tablets can be taken with or without food. Drink plenty of water when taking TMP/SMX. WHAT ARE THE SIDE EFFECTS? HIV infection causes higher rates of TMP/SMX side effects. People who have taken TMP/SMX before often have more side effects. The main side effects of TMP/SMX are nausea, vomiting, loss of appetite, and allergic skin reactions (rashes.) The skin rashes can be fairly common. TMP/SMX can cause Stevens-Johnson syndrome, a very serious skin rash. TMP/SMX can also cause neutropenia, a low level of neutrophils. These are white blood cells that fight bacterial infections. HIV infection can also cause neutropenia. Some health care providers use a "desensitization" procedure with patients who get an allergic reaction. Starting with a very low dose of TMP/SMX that does not cause an allergic reaction, they gradually increase the dose to the full amount. Vitamin C may help in cases of allergic reactions to Bactrim. Another option is to use the drug Dapsone (see fact sheet 533). TMP/SMX can also make you sensitive to sunlight. If this occurs, use sun block on your skin and/or wear sunglasses. Tell your health care provider if your skin gets pale or yellowish, or you get a sore throat, fever, or rash, even after a few weeks of taking TMP/SMX. These might indicate a serious drug reaction. HOW DOES TMP/SMX REACT WITH OTHER DRUGS? TMP/SMX is mostly processed by the kidneys. It does not interact very much with drugs that use the liver, including most antiretroviral drugs used to fight HIV. However, TMP/SMX interacts with several other types of drugs, including some blood thinners, pills to lower blood sugar, seizure medications, and water pills. Be sure your health care provider knows about all the medications you are taking. The risk of developing anemia is higher if you take TMP/SMX at the same time as other drugs that can cause it, such as AZT (Retrovir, see fact sheet 411). The risk of developing neutropenia is higher if you take TMP/SMX at the same time as other drugs that can cause it, such as AZT or ganciclovir. source: The AIDS Infonet

WHAT IS PCP? HOW IS PCP TREATED? CAN PCP BE PREVENTED? WHICH DRUG IS BEST? THE BOTTOM LINE WHAT IS PCP? Pneumocystis pneumonia (PCP or pneumocystis) is the most common opportunistic infection in people with HIV. Without treatment, over 85% of people with HIV would eventually develop PCP. It has been the major killer of people with HIV. However, PCP is now almost entirely preventable and treatable. PCP is caused by a fungus. It used to be called pneumocystis carinii, but scientists now call it pneumocystis jiroveci. A healthy immune system can control the fungus. However, PCP causes illness in children and in adults with a weakened immune system. Pneumocystis almost always affects the lungs, causing a form of pneumonia. People with CD4 cell counts under 200 have the highest risk of developing PCP. People with counts under 300 who have already had another opportunistic infection are also at risk. Most people who get PCP become much weaker, lose a lot of weight, and are likely to get PCP again. The first signs of PCP are difficulty breathing, fever, and a dry cough. Anyone with these symptoms should see a doctor immediately. However, everyone with CD4 counts below 300 should discuss PCP prevention with their doctor, before they experience any symptoms. HOW IS PCP TREATED? For many years, antibiotics were used to prevent PCP in cancer patients with weakened immune systems. It was not until 1985 that a small study showed that these drugs would also prevent PCP in people with AIDS. The success in preventing and treating PCP is dramatic. Percentages have been cut by about half for PCP as the first AIDS-defining diagnosis, and for PCP as the cause of death of people with AIDS. Unfortunately, PCP is still common in people who are infected with HIV for a long time before getting treatment. In fact, 30% to 40% of people with HIV develop PCP if they wait to get treatment until their CD4 cell counts are around 50. A new anti-PCP drug, DB289, is being studied in a Phase II trial. Early clinical trials showed very good results. The drugs now used to treat PCP include TMP/SMX, dapsone, pentamidine, and atovaquone. TMP/SMX (Bactrim® or Septra®) is the most effective anti-PCP drug. It’s a combination of two antibiotics: trimethoprim (TMP) and sulfamethoxazole (SMX). Dapsone is similar to TMP/SMX. Dapsone seems to be almost as effective as TMP/SMX against PCP. Pentamidine (NebuPent®, Pentam®, Pentacarinat®) is a drug that is usually inhaled in an aerosol form to prevent PCP. Pentamidine is also used intravenously (IV) to treat active PCP. Atovaquone (Mepron®) is a drug used in people with mild or moderate cases of PCP who can not take TMP/SMX or pentamidine. CAN PCP BE PREVENTED? The best way to prevent PCP is to use strong antiretroviral therapy (ART). People who have less than 200 CD4 cells can prevent PCP by taking the same medications used for PCP treatment Combination ART can make your CD4 cell count go up. If it goes over 200 and stays there for 3 months, it may be safe to stop taking PCP medications. However, because PCP medications are inexpensive and have mild side effects, some researchers think they should be continued until your CD4 cell count reaches 300. Be sure to talk with your doctor before you stop taking any of your prescribed medications. WHICH DRUG IS BEST? Bactrim or Septra (TMP/SMX) is the most effective drug against PCP. It is also inexpensive, costing only about $10 per month. It is taken in pill form, not more than one pill daily. Cutting back from one pill a day to three pills a week reduces the allergy problems of Bactrim and Septra, and seems to work just as well. However, the “SMX” part is a sulfa drug and almost half of the people who take it have an allergic reaction. This usually is a skin rash, sometimes a fever. Allergic reactions can be overcome using a desensitization procedure. Patients start with a very small amount of the drug and take increasing amounts until they can tolerate the full dose. Dapsone causes fewer allergic reactions than TMP/SMX. It is also fairly inexpensive – about $30 per month. It also is taken as a pill and, like Bactrim or Septra, not more than one pill daily. Pentamidine involves a monthly visit to a clinic with a nebulizer, the machine that produces a very fine mist of the drug. The mist is inhaled directly into the lungs. The procedure takes about 30 to 45 minutes. You pay for the drug plus the clinic costs, between $120 and $250 per month. Patients using aerosol pentamidine get PCP more often than people taking the antibiotic pills. THE BOTTOM LINE PCP, which was the number one killer of people with HIV, is now almost totally treatable and preventable. Strong antiretroviral drugs (ARVs) can keep your CD4 count from dropping. If your CD4 cell count is below 300, talk to your doctor about taking drugs to prevent PCP. Everyone whose CD4 cell count is below 200 should be taking anti-PCP medication. source: The AIDS Infonet

WHAT IS ACUTE HIV INFECTION? TESTING FOR ACUTE HIV INFECTION RISK OF IMMUNE DAMAGE RISK OF INFECTING OTHERS TREATING ACUTE HIV INFECTION PROS AND CONS OF TREATING ACUTE HIV THE BOTTOM LINE WHAT IS ACUTE HIV INFECTION? The amount of HIV in the blood gets very high within a few days or weeks after HIV infection. Some people get a flu-like illness. This first stage of HIV disease is called "acute HIV infection" or "primary HIV infection." About half of the people who get infected don?t notice anything. Symptoms generally occur within 2 to 4 weeks. The most common symptoms are fever, fatigue, and rash. Others include headache, swollen lymph glands, sore throat, feeling achy, nausea, vomiting, diarrhea, and night sweats. It is easy to overlook the signs of acute HIV infection. They can be caused by several different illnesses. If you have any of these symptoms and if there is any chance that you were recently exposed to HIV, talk to your health care provider about getting tested for HIV. TESTING FOR ACUTE HIV INFECTION The normal HIV blood test will come back negative for someone who was infected very recently. The test looks for antibodies produced by the immune system to fight HIV. It can take two months for these antibodies to be produced. See fact sheet 102 for more information. However, the viral load test (see fact sheet 125) measures the virus itself. Before the immune system produces antibodies to fight it, HIV multiplies rapidly. Therefore, this test will show a high viral load during acute infection. A negative HIV antibody test and a very high viral load indicate recent HIV infection, most likely within the past two months. If both tests are positive, then HIV infection probably occurred a few months or longer before the tests. A special "detuned" version of the HIV antibody test is less sensitive. It detects only those infections that occurred at least four to six months before testing. It can be used to help identify cases of acute HIV infection. RISK OF IMMUNE DAMAGE Some people think that there?s not much harm done in the early stages of HIV infection. They believe that any damage to their immune system will be cured by taking antiretroviral therapy (ART). This is not true! Up to 60% of infection-fighting ?memory? CD4 cells are infected during acute infection, and after 14 days of infection, up to half of all memory CD4 cells can be killed. Also, HIV quickly reduces the ability of the thymus gland to replace lost CD4 cells. The lining of the intestine is also damaged very quickly. This can all occur before a person tests positive for HIV. RISK OF INFECTING OTHERS The number of HIV particles in the blood is much higher during acute HIV infection than later on. Exposure to the blood of someone in the acute phase of infection is more likely to result in infection than exposure to someone with long-term infection. One research study estimated that the risk of infection is approximately 20 times higher during acute HIV infection. TREATING ACUTE HIV INFECTION At first, the immune system produces white blood cells that recognize and kill HIV-infected cells. This is called an "HIV-specific response." Over time, most people lose this response. Unless they use antiretroviral drugs (ARVs), their HIV disease will progress. Guidelines for using HIV medications recommend waiting until the immune system shows signs of damage. However, starting ARVs during acute HIV infection might protect the HIV-specific immune response. Researchers have studied people who start treatment during acute infection and then stop taking ARVs. One study showed that this treatment may delay the time until ART is needed. Researchers are doing more studies. PROS AND CONS OF TREATING ACUTE HIV INFECTION Starting ART is a major decision. Anyone thinking about taking ARVs should carefully consider the benefits and disadvantages. Taking ART changes your daily life. Missing doses of drugs makes it easier for the virus to develop resistance to medications, which limits future treatment options. Fact Sheet 405 has more information about the importance of taking ARVs correctly. The medications are very strong. They have side effects that can be difficult to live with for a long time, and they can be very expensive. Early treatment can protect the immune system from damage by HIV. Immune damage shows up as lower CD4 cell counts and higher viral loads. These are associated with higher rates of disease. Older people (over 40 years old) have weaker immune systems. They do not respond to ARVs as well as younger people. However, not everyone with HIV gets sick right away. Someone with a CD4 cell count over 350 and a viral load under 20,000, even if they don?t take antiviral drugs, has about a 50/50 chance of staying healthy for 6 to 9 years. Fact Sheet 124 has more information on CD4 cell tests, and Fact Sheet 125 has information on the viral load. At first, researchers believed that early treatment might allow a patient to stop taking ART after a period of controlling HIV. However, newer reports indicate that this is very unusual. THE BOTTOM LINE It?s not easy to identify people with acute HIV infection. Some people have no symptoms. If they have symptoms, several other diseases like the flu might be causing them. If you think you might be in the acute stage of HIV infection, tell your health care provider and get tested. Talk to your health care provider about the possible advantages of starting ART during acute HIV infection. Taking ARVs is a major commitment. Discuss the pros and cons of treatment with your health care provider and consider them carefully before making any decisions. source: The AIDS Infonet

WHAT ARE OPPORTUNISTIC INFECTIONS? TESTING FOR OIs OIs AND AIDS WHAT ARE THE MOST COMMON OIs? PREVENTING OIs TREATING OIs WHAT ARE OPPORTUNISTIC INFECTIONS? In our bodies, we carry many germs – bacteria, protozoa, fungi, and viruses. When our immune system is working, it controls these germs. But when the immune system is weakened by HIV disease or by some medications, these germs can get out of control and cause health problems. Infections that take advantage of weakness in the immune defenses are called “opportunistic”. The phrase “opportunistic infection” is often shortened to “OI”. TESTING FOR OIs You can be infected with an OI, and “test positive” for it, even though you don’t have the disease. For example, almost everyone with HIV tests positive for Cytomegalovirus (CMV). But it is very rare for CMV disease to develop unless the CD4 cell count drops below 50, a sign of serious damage to the immune system. To see if you’re infected with an OI, your blood might be tested for antigens (pieces of the germ that causes the OI) or for antibodies (proteins made by the immune system to fight the germs). If the antigens are found, it means you?re infected. If the antibodies are found, you?ve been exposed to the infection. You may have been immunized against the infection, or your immune system may have ?cleared? the infection, or you may be infected. If you are infected with a germ that causes an OI, and if your CD4 cells are low enough to allow that OI to develop, your health care provider will look for signs of active disease. These are different for the different OIs. OIs AND AIDS People who aren’t HIV-infected can develop OIs if their immune systems are damaged. For example, many drugs used to treat cancer suppress the immune system. Some people who get cancer treatments can develop OIs. HIV weakens the immune system so that opportunistic infections can develop. If you are HIV-infected and develop opportunistic infections, you might have AIDS. In the US, the Center for Disease Control (CDC) is responsible for deciding who has AIDS. The CDC has developed a list of about 24 opportunistic infections. If you have HIV and one or more of these “official” OIs, then you have AIDS. The list is available at https://www.aidsmeds.com/lessons/StartHere8.htm. WHAT ARE THE MOST COMMON OIs? In the early years of the AIDS epidemic, OIs caused a lot of sickness and deaths. Once people started taking strong antiretroviral therapy (ART), however, a lot fewer people got OIs. It’s not clear how many people with HIV will get a specific OI. In women, health problems in the vaginal area may be early signs of HIV. These can include pelvic inflammatory disease and bacterial vaginosis, among others. See fact sheet 610 for more information. The most common OIs are listed here, along with the disease they usually cause, and the CD4 cell count when the disease becomes active: Candidiasis (Thrush) is a fungal infection of the mouth, throat, or vagina. CD4 cell range: can occur even with fairly high CD4 cells. Cytomegalovirus (CMV) is a viral infection that causes eye disease that can lead to blindness.CD4 cell range: under 50. Herpes simplex viruses can cause oral herpes (cold sores) or genital herpes. These are fairly common infections, but if you have HIV, the outbreaks can be much more frequent and more severe. They can occur at any CD4 cell count. Malaria is common in the developing world. It is more common and more severe in people with HIV infection. Mycobacterium avium complex (MAC or MAI) is a bacterial infection that can cause recurring fevers, general sick feelings, problems with digestion, and serious weight loss. CD4 cell range: under 75. Pneumocystis pneumonia (PCP) is a fungal infection that can cause a fatal pneumonia. CD4 cell range: under 200. Unfortunately this is still a fairly common OI in people who have not been tested or treated for HIV. Toxoplasmosis (Toxo) is a protozoal infection of the brain. T-cell range: under 100. Tuberculosis (TB) is a bacterial infection that attacks the lungs, and can cause meningitis. CD4 cell range: Everyone with HIV who tests positive for exposure to TB should be treated. PREVENTING OIs Most of the germs that cause OIs are quite common, and you may already be carrying several of these infections. You can reduce the risk of new infections by keeping clean and avoiding known sources of the germs that cause OIs. Even if you’re infected with some OIs, you can take medications that will prevent the development of active disease. This is called prophylaxis. The best way to prevent OIs is to take strong ART. See Fact Sheet 403 for more information on ART. The Fact Sheets for each OI have more information on avoiding infection or preventing the development of active disease. TREATING OIs For each OI, there are specific drugs, or combinations of drugs, that seem to work best. Refer to the Fact Sheets for each OI to learn more about how they are treated. Strong antiretroviral drugs can allow a damaged immune system to recover and do a better job of fighting OIs. Fact Sheet 481 on Immune Restoration has more information on this topic. source: The AIDS Infone

WHAT ARE CD4 CELLS? WHY ARE CD4 CELLS IMPORTANT IN HIV? WHAT FACTORS INFLUENCE A CD4 CELL COUNT? HOW ARE THE TEST RESULTS REPORTED? WHAT DO THE NUMBERS MEAN? WHAT ARE CD4 CELLS? CD4 cells are a type of lymphocyte (white blood cell). They are an important part of the immune system. CD4 cells are sometimes called T-cells. There are two main types of T-cells. T-4 cells, also called CD4+, are “helper” cells. They lead the attack against infections. T-8 cells, (CD8+), are “suppressor” cells that end the immune response. CD8+ cells can also be ?killer? cells that kill cancer cells and cells infected with a virus. Researchers can tell these cells apart by specific proteins on the cell surface. A T-4 cell is a T-cell with CD4 molecules on its surface. This type of T-cell is also called ?CD4 positive,? or CD4+. WHY ARE CD4 CELLS IMPORTANT IN HIV? When HIV infects humans, the cells it infects most often are CD4 cells. The virus becomes part of the cells, and when they multiply to fight an infection, they also make more copies of HIV. When someone is infected with HIV for a long time, the number of CD4 cells they have (their CD4 cell count) goes down. This is a sign that the immune system is being weakened. The lower the CD4 cell count, the more likely the person will get sick. There are millions of different families of CD4 cells. Each family is designed to fight a specific type of germ. When HIV reduces the number of CD4 cells, some of these families can be totally wiped out. You can lose the ability to fight off the particular germs those families were designed for. If this happens, you might develop an opportunistic infection (See Fact Sheet 500). WHAT FACTORS INFLUENCE A CD4 CELL COUNT? The CD4 cell value bounces around a lot. Time of day, fatigue, and stress can affect the test results. It’s best to have blood drawn at the same time of day for each CD4 cell test, and to use the same laboratory. Infections can have a large impact on CD4 cell counts. When your body fights an infection, the number of white blood cells (lymphocytes) goes up. CD4 and CD8 counts go up, too. Vaccinations can cause the same effects. Don’t check your CD4 cells until a couple of weeks after you recover from an infection or get a vaccination. HOW ARE THE TEST RESULTS REPORTED? CD4 cell tests are normally reported as the number of cells in a cubic millimeter of blood, or mm3. There is some disagreement about the normal range for CD4 cell counts, but normal CD4 counts are between 500 and 1600, and CD8 counts are between 375 and 1100. CD4 counts drop dramatically in people with HIV, in some cases down to zero. The ratio of CD4 cells to CD8 cells is often reported. This is calculated by dividing the CD4 value by the CD8 value. In healthy people, this ratio is between 0.9 and 1.9, meaning that there are about 1 to 2 CD4 cells for every CD8 cell. In people with HIV infection, this ratio drops dramatically, meaning that there are many times more CD8 cells than CD4 cells. Because the CD4 counts are so variable, some health care providers prefer to look at the CD4 percentages. These percentages refer to total lymphocytes. If your test reports CD4% = 34%, that means that 34% of your lymphocytes were CD4 cells. This percentage is more stable than the number of CD4 cells. The normal range is between 20% and 40%. A CD4 percentage below 14% indicates serious immune damage. It is a sign of AIDS in people with HIV infection. A recent study showed that the CD4% is a predictor of HIV disease progression. WHAT DO THE NUMBERS MEAN? The meaning of CD8 cell counts is not clear, but it is being studied. The CD4 cell count is a key measure of the health of the immune system. The lower the count, the greater damage HIV has done. Anyone who has less than 200 CD4 cells, or a CD4 percentage less than 14%, is considered to have AIDS according to the US Centers for Disease Control. CD4 counts are used together with the viral load to estimate how long someone will stay healthy. See Fact Sheet 125 for more information on the viral load test. CD4 counts are also used to indicate when to start certain types of drug therapy: When to start antiretroviral therapy (ART): When the CD4 count goes below 350, most health care providers begin ART (see Fact Sheet 403). Also, some health care providers use the CD4% going below 15% as a sign to start aggressive ART, even if the CD4 count is high. More conservative health care providers might wait until the CD4 count drops to near 200 before starting treatment. A recent study found that starting treatment with a CD4% below 5% was strongly linked to a poor outcome. When to start drugs to prevent opportunistic infections: Most health care providers prescribe drugs to prevent opportunistic infections at the following CD4 levels: Less than 200: pneumocystis pneumonia (PCP) Less than 100: toxoplasmosis and cryptococcosis Less than 75: mycobacterium avium complex (MAC). Because they are such an important indicator of the strength of the immune system, official treatment guideline in the US suggest that CD4 counts be monitored every 3 to 4 months. See Fact Sheet 404 for more information on the treatment guidelines. source: The AIDS Infonet

WHAT IS HIV TESTING? HOW DO I GET TESTED? WHEN SHOULD I GET TESTED? DO ANY TESTS WORK SOONER AFTER INFECTION? WHAT DOES IT MEAN IF I TEST POSITIVE? CAN I KEEP THE TEST RESULTS CONFIDENTIAL? HOW ACCURATE ARE THE TESTS? THE BOTTOM LINE WHAT IS HIV TESTING? HIV testing tells you if you are infected with the Human Immunodeficiency Virus (HIV) which causes AIDS. These tests look for “antibodies” to HIV. Antibodies are proteins produced by the immune system to fight a specific germ. Other “HIV” tests are used when people already know that they are infected with HIV. These help measure how quickly the virus is multiplying (a viral load test) or the health of your immune system (a CD4 count). For more information, see Fact Sheet 124 (T-cell Tests), and Fact Sheet 125 (Viral Load Tests). HOW DO I GET TESTED? In September 2006, the US Centers for Disease Control recommended routine HIV screening of people in healthcare settings. This should result in more general HIV testing in the US. You can arrange for HIV testing at any Public Health office, or at your doctor’s office. Test results are usually available within two weeks. In the US, call the National AIDS Hotline, (800) 342-2437. The most common HIV test is a blood test. Newer tests can detect HIV antibodies in mouth fluid (not the same as saliva), a scraping from inside the cheek, or urine. “Rapid” HIV test results are available within 10 to 30 minutes after a sample is taken. One of these tests has produced a high rate of false positives. A positive result on any HIV test should be confirmed with a second test. Home test kits: You can’t test yourself for HIV at home. The Home Access test kit is only designed to collect a sample of your blood. You send the sample to a laboratory where it is tested for HIV. WHEN SHOULD I GET TESTED? If you become infected with HIV, it usually takes between three weeks and two months for your immune system to produce antibodies to HIV. If you think you were exposed to HIV, you should wait for two months before being tested. You can also test right away and then again after two or three months. During this “window period” an antibody test may give a negative result, but you can transmit the virus to others if you are infected. About 5% of people take longer than two months to produce antibodies. There is one documented case of a person exposed to HIV and hepatitis C at the same time. Antibodies to HIV were not detected until one year after exposure. Testing at 3 and 6 months after possible exposure will detect almost all HIV infections. However, there are no guarantees as to when an individual will produce enough antibodies to be detected by an HIV test. If you have any unexplained symptoms, talk with your health care provider and consider re-testing for HIV. DO ANY TESTS WORK SOONER AFTER INFECTION? Viral load tests detect pieces of HIV genetic material. They show up before the immune system manufactures antibodies. Also, in early 2002, the FDA approved “nucleic acid testing.” It is similar to viral load testing. Blood banks use it to screen donated blood. The viral load or nucleic acid tests are generally not used to see if someone has been infected with HIV because they are much more expensive than an antibody test. They also have a slightly higher error rate. WHAT DOES IT MEAN IF I TEST POSITIVE? A positive test result means that you have HIV antibodies, and are infected with HIV. You will get your test result from a counselor who should tell you what to expect, and where to get health services and emotional support. Testing positive does not mean that you have AIDS (See Fact Sheet 101, What is AIDS?). Many people who test positive stay healthy for several years, even if they don’t start taking medication right away. If you test negative and you have not been exposed to HIV for at least three months, you are not infected with HIV. Continue to protect yourself from HIV infection (See Fact Sheet 150, Stopping the Spread of HIV). CAN I KEEP THE TEST RESULT CONFIDENTIAL? You can be tested anonymously in many places. You do not have to give your name when you are tested at a public health office, or when you receive the test results. You can be tested anonymously for HIV as many times as you want. If you get a positive HIV test that is not anonymous, or if you get any medical services for HIV infection, your name may be reported to the Department of Health. The Centers for Disease Control (CDC) proposed in late 1998 that all states keep track of the names of HIV-infected people. This proposal has not yet taken effect. HOW ACCURATE ARE THE TESTS? Antibody test results for HIV are accurate more than 99.5% of the time. Before you get the results, the test has usually been done two or more times. The first test is called an “EIA” or “ELISA” test. Before a positive ELISA test result is reported, it is confirmed by another test called a “Western Blot”. Two special cases can lead to false results: Children born to HIV-positive mothers may have false positive test results for several months because mothers pass infection-fighting antibodies to their newborn children. Even if the children are not infected with HIV, they have HIV antibodies and will test positive. Other tests, such as a viral load test, must be used. As mentioned above, people who were recently infected may test negative if they get tested too soon after being infected with HIV. THE BOTTOM LINE HIV testing generally looks for HIV antibodies in the blood, or saliva or urine. The immune system produces these antibodies to fight HIV. It usually takes two to three months for them to show up. In

WHAT’S MY RISK OF GETTING INFECTED WITH HIV? THERE ARE NO GUARANTEES! WHAT DO THE NUMBERS MEAN? WHAT ACTIVITIES ARE MOST RISKY? WHAT ABOUT ORAL SEX? WHAT INCREASES THE RISK OF HIV INFECTION? THE BOTTOM LINE WHAT’S MY RISK OF GETTING INFECTED WITH HIV? Most people know how HIV is transmitted (see fact sheet 150). They also know about safer sex guidelines (see fact sheet 151). However, they may still be exposed to HIV. This can be by accident or because they take part in some risky behavior. When this happens, they always want to know how likely it is that they got infected with HIV. THERE ARE NO GUARANTEES! You can’t be sure that you’re not infected with HIV unless you are 100% certain that you did not engage in any risky behavior and that you were not exposed to any HIV-infected fluids. The only way to know for sure whether you have been infected is to get tested. You should wait for 3 months after a possible exposure. Then get an HIV blood test (see fact sheet 102). You might feel that you have been exposed to HIV by sharing needles, an accident, or unsafe sexual activity. In these cases, talk to your health care provider immediately . Ask whether you can use HIV treatments to prevent infection. Fact sheet 156 has more information on "post-exposure prophylaxis." WHAT DO THE NUMBERS MEAN? In the late 1980s and early 1990s, several studies were done to assess the risks of HIV infection from specific types of exposure to HIV. These calculations only give a general idea of risk. They can tell you which activities carry a higher or lower risk. They cannot tell you if you have been infected. If the risk is 1 in 100, for example, it doesn?t mean that you can engage in that activity 99 times without any risk of becoming infected. You might become infected with HIV after a single exposure. That can happen the first time you engage in a risky activity. Also, these studies were based on a specific group of people. There is no reason to believe that the results apply to other groups, or to the general population. WHAT ACTIVITIES ARE MOST RISKY? The highest risk of becoming infected with HIV is from sharing needles to inject drugs with someone who is infected with HIV. When you share needles, there is a very high probability that someone else’s blood will be injected into your bloodstream. Hepatitis virus can also be transmitted by sharing needles. The next greatest risk for HIV infection is from unprotected sexual intercourse (without a condom). Receptive anal intercourse carries the highest risk. The lining of the rectum is very thin. It is damaged very easily during sexual activity. This makes it easier for HIV to enter the body. The "top" or active partner in anal intercourse seems to run a much lower risk. However, the risk still seems higher than for the active partner in insertive vaginal intercourse. Receptive vaginal intercourse has the next highest risk. The lining of the vagina is stronger than in the rectum, but is vulnerable to infection. Also, it can be damaged by sexual activity. All it takes is a tiny scrape that can be too small to see. The risk of infection is increased if there is any inflammation or infection in the vagina. The risk is higher for the receptive partner. However, there is some risk for the active partner in anal or vaginal sex. It’s possible for HIV to enter the penis through any open sores, through the moist lining of the opening of the penis, or through the cells in the mucous membrane in the foreskin or the head of the penis. WHAT ABOUT ORAL SEX? There have been many studies of HIV transmission through oral sex. They have not come to clear conclusions. However, the following points are clear: It is possible to get infected with HIV through oral sex. The risk is not zero. The risk of HIV infection through oral sex is extremely low. It is much lower than for other types of unprotected sexual activity. However, other diseases such as syphilis can be transmitted through oral sex. WHAT INCREASES THE RISK OF HIV INFECTION? Syphilis can increase the risk of transmitting HIV. People with syphilis have a higher than average chance of being infected with HIV. Also, syphilis causes large, painless sores. It is easy for someone to be infected with HIV through syphilis sores. Herpes simplex infection (see Fact Sheet 508) also causes sores which assist infection with HIV. An active case of syphilis or herpes increases the amount of HIV in someone’s system and can make it easier for them to pass it on to another person. Several other factors increase the risk of transmitting HIV, or becoming infected. When the HIV-infected person is in the "acute infection" phase (see fact sheet 103), the amount of virus in their blood is very high. This increases the chance that they can pass on the infection. Unfortunately, almost no one knows when they are in this phase of HIV infection. There’s no way to tell by looking at them. When either person has a weakened immune system. This could be because of a long-term illness or an active infection like a herpes outbreak, syphilis, or the flu. When the uninfected person has open sores that get exposed to infected fluids. These could be cold sores, genital herpes, mouth ulcers, syphilis sores, or other cuts or breaks in the skin. When there is exposure to infected blood. When the uninfected insertive male partner is not circumcised. THE BOTTOM LINE Researchers have developed estimates of the risk of transmission of HIV. These estimates can give you a general idea of which activities are more or less risky. They cannot tell you that any activity is safe, or how many times you can do them without getting infected. The best way to avoid infection is to

HOW DOES DRUG USE RELATE TO HIV? INJECTION AND INFECTION NEEDLE EXCHANGE PROGRAMS DRUG USE AND UNSAFE SEX MEDICATIONS AND DRUGS THE BOTTOM LINE HOW DOES DRUG USE RELATE TO HIV? Drug use is a major factor in the spread of HIV infection. Shared equipment for using drugs can carry HIV and hepatitis, and drug use is linked with unsafe sexual activity. Drug and alcohol use can also be dangerous for people who are taking antiretroviral medications (ARVs). Drug users are less likely to take all of their medications, and street drugs may have dangerous interactions with ARVs. Fact sheet 494 has more information on individual drugs and HIV. INJECTION AND INFECTION HIV infection spreads easily when people share equipment to use drugs. Sharing equipment also spreads hepatitis B, hepatitis C, and other serious diseases. Infected blood can be drawn up into a syringe and then get injected along with the drug by the next user of the syringe. This is the easiest way to transmit HIV during drug use because infected blood goes directly into someone’s bloodstream. Even small amounts of blood on your hands, cookers, filters, tourniquets, or in rinse water can be enough to infect another user. To reduce the risk of HIV and hepatitis infection, never share any equipment used with drugs, and keep washing your hands. Carefully clean your cookers and the site you will use for injection. See fact sheet 155 for more information on ways to reduce the harm of drug use. A recent study showed that HIV can survive in a used syringe for at least 4 weeks. If you have to re-use equipment, you can reduce the risk of infection by cleaning it between users. If possible, re-use your own syringe. It still should be cleaned because bacteria can grow in it. The most effective way to clean a syringe is to use water first, then bleach and a final water rinse. Try to get all blood out of the syringe by shaking vigorously for 30 seconds. Use cold water because hot water can make the blood form clots. To kill most HIV and hepatitis C virus, leave bleach in the syringe for two full minutes. Cleaning does not always kill HIV or hepatitis. Always use a new syringe if possible. NEEDLE EXCHANGE PROGRAMS Some communities have started needle exchange programs to give free, clean syringes to people so they won’t need to share. These programs are controversial because some people think they promote drug use. However, research on needle exchange shows that this is not true. Rates of HIV infection go down where there are needle exchange programs, and more drug users sign up for treatment programs. The North American Syringe Exchange Network has a web page listing several needle exchange programs at https://www.nasen.org/ DRUG USE AND UNSAFE SEX For a lot of people, drugs and sex go together. Drug users might trade sex for drugs or for money to buy drugs. Some people connect having unsafe sex with their drug use. Drug use, including methamphetamine or alcohol, increases the chance that people will not protect themselves during sexual activity. Someone who is trading sex for drugs might find it difficult to set limits on what they are willing to do. Drug use can reduce a person’s commitment to use condoms and practice safer sex. Often, substance users have multiple sexual partners. This increases their risk of becoming infected with HIV or another sexually transmitted disease. Also, substance users may have an increased risk of carrying sexually transmitted diseases. This can increase their risk of becoming infected with HIV, or of transmitting HIV infection. MEDICATIONS AND DRUGS It is very important to take every dose of ARVs. People who are not adherent (miss doses) are more likely to have higher levels of HIV in their blood, and to develop resistance to their medications. Drug use is linked with poor adherence, which can lead to treatment failure. Some street drugs interact with medications. The liver breaks down some medications used to fight HIV, especially the protease inhibitors and the non-nucleoside analog reverse transcriptase inhibitors. It also breaks down some recreational drugs, including alcohol. When drugs and medications are both “in line” to use the liver, they might both be processed much more slowly. This can lead to a serious overdose of the medication or of the recreational drug. An overdose of a medication can cause serious side effects. An overdose of a recreational drug can be deadly. At least one death of a person with HIV has been blamed on mixing a protease inhibitor with the recreational drug Ecstasy. Some ARVs can change the amount of methadone in the bloodstream. It may be necessary to adjust the dosage of methadone in some cases. See the fact sheets for each of the medications you are taking, and discuss your HIV medications with your methadone counselor. THE BOTTOM LINE Drug use is a major cause of new HIV infections. Shared equipment can spread HIV, hepatitis, and other diseases. Alcohol and drug use, even when just used recreationally, contribute to unsafe sexual activities. To protect yourself from infection, never re-use any equipment for using drugs. Even if you re-use your own syringes, clean them thoroughly between times. Cleaning is only partly effective. In some communities, needle exchange programs provide free, new syringes. These programs reduce the rate of new HIV infections. Drug use can lead to missed doses of ARVs. This increases the chances of treatment failure and resistance to medications. Mixing recreational drugs and ARVs can be dangerous. Drug interactions can cause serious side effects or dangerous overdoses. source: The AIDS Infonet

WHAT IS VIRAL LOAD? HOW IS THE TEST USED? HOW ARE CHANGES IN VIRAL LOAD MEASURED? VIRAL LOAD “BLIPS” WHAT DO THE NUMBERS MEAN? ARE THERE PROBLEMS WITH THE VIRAL LOAD TEST? WHAT IS VIRAL LOAD? The viral load test measures the amount of HIV virus in your blood. There are different techniques for doing this: The PCR (polymerase chain reaction) method uses an enzyme to multiply the HIV in the blood sample. Then a chemical reaction marks the virus. The markers are measured and used to calculate the amount of virus. Roche and Abbott produce this type of test. The bDNA (branched DNA) method combines a material that gives off light with the sample. This material connects with the HIV particles. The amount of light is measured and converted to a viral count. Bayer produces this test. The NASBA (nucleic acid sequence based amplification) method amplifies viral proteins to derive a count. It is manufactured by bioMerieux. Different test methods often give different results for the same sample. Because the tests are different, you should stick with the same kind of test (PCR or bDNA) to measure your viral load over time. Viral loads are usually reported as copies of HIV in one milliliter of blood. The tests count up to about 1 million copies, and are always being improved to be more sensitive. The first bDNA test measured down to 10,000 copies. The second generation could detect as few as 500 copies. Now there are ultra sensitive tests for research that can detect less than 5 copies. The best viral load test result is “undetectable.” This does not mean that there is no virus in your blood; it just means that there is not enough for the test to find and count. With the first viral load tests, “undetectable” meant up to 9,999 copies! “Undetectable” depends on the sensitivity of the test used on your blood sample. The first viral load tests all used frozen blood samples. Good results have been obtained using dried samples. This will reduce costs for freezers and shipping. HOW IS THE TEST USED? The viral load test is helpful in several areas: For medical researchers, the test has been used to prove that HIV is never “latent” but is always multiplying. Many people with no symptoms of AIDS and high CD4 cell counts also had high viral loads. If the virus was latent, the test wouldn’t have found any HIV in the blood. The test can be used for diagnosis, because it can detect a viral load a few days after HIV infection. This is better than the standard HIV (antibody) test, which can be “negative” for 2 to 6 months after HIV infection. (See Fact Sheet 102 for more information on HIV antibody testing.) For prognosis, viral load can help predict how long someone will stay healthy. The higher the viral load, the faster HIV disease progresses. For prevention, viral load predicts how easy it is to transmit HIV to someone else. The higher the viral load, the higher the risk of transmitting HIV. Finally, the viral load test is valuable for managing therapy, to see if antiretroviral drugs are controlling the virus. Current guidelines suggest measuring baseline (pre-treatment) viral load. A drug is “working” if it lowers viral load by at least 90% within 8 weeks. The viral load should continue to drop to less than 50 copies within 6 months. The viral load should be measured within 2 to 8 weeks after treatment is started or changed, and every 3 to 4 months after that. HOW ARE CHANGES IN VIRAL LOAD MEASURED? Repeat tests of the same blood sample can give results that vary by a factor of 3. This means that a meaningful change would be a drop to less than 1/3 or an increase to more than 3 times the previous test result. For example, a change from 200,000 to 600,000 is within the normal variability of the test. A drop from 50,000 to 10,000 would be significant. The most important change is to reach an undetectable viral load. Viral load changes are often described as “log” changes. This refers to scientific notation, which uses powers of 10. For example, a 2-log drop is a drop of 102 or 100 times. A drop from60,000 to 600 would be a 2-log drop. VIRAL LOAD “BLIPS” Recently, researchers have noticed that the viral load of many patients sometimes went from undetectable to a low level (usually less than 500) and then returned to undetectable. Careful study suggests that these ?blips? do not indicate that the virus is developing resistance. WHAT DO THE NUMBERS MEAN? There are no “magic” numbers for viral loads. We don’t know how long you’ll stay healthy with any particular viral load. All we know so far is that lower is better and seems to mean a longer, healthier life. US treatment guidelines (See Fact Sheet 404) suggest that anyone with a viral load over 100,000 should be offered treatment. Some people may think that if their viral load is undetectable, they can’t pass the HIV virus to another person. This is not true. There is no “safe” level of viral load. Although the risk is less, you can pass HIV to another person even if your viral load is undetectable. ARE THERE PROBLEMS WITH THE VIRAL LOAD TEST? There are some concerns with the viral load test: Only about 2% of the HIV in your body is in the blood. The viral load test does not measure how much HIV is in body tissues like the lymph nodes, spleen, or brain. HIV levels in lymph tissue and semen go down when blood levels go down, but not at the same time or the same rate. The viral load test results can be thrown off if your body is fighting an infection, or if you have just received an immunization (like a flu shot). You should not have blood taken for a viral load test within

WHAT ARE CONDOMS? WHAT ARE THEY MADE OF? HOW ARE CONDOMS USED? Using a Male Condom Using a Female Condom NONOXYNOL-9 CONDOM MYTHS THE BOTTOM LINE WHAT ARE CONDOMS? A condom is a tube made of thin, flexible material. It is closed at one end. Condoms have been used for hundreds of years to prevent pregnancy by keeping a man’s semen out of a woman’s vagina. Condoms also help prevent diseases that are spread by semen or by contact with infected sores in the genital area, including HIV. Most condoms go over a man’s penis. A new type of condom was designed to fit into a woman’s vagina. This “female” condom can also be used to protect the rectum. WHAT ARE THEY MADE OF? Condoms used to be made of natural skin (including lambskin) or of rubber. That’s why they are called “rubbers.” Most condoms today are latex or polyurethane. Lambskin condoms can prevent pregnancy. However, they have tiny holes (pores) that are large enough for HIV to get through. Lambskin condoms do not prevent the spread of HIV. Latex is the most common material for condoms. Viruses can not get through it. Latex is inexpensive and available in many styles. It has two drawbacks: oils make it fall apart, and some people are allergic to it. Polyurethane is an option for people who are allergic to latex. One brand of female condom and one brand of male condom are made of polyurethane. HOW ARE CONDOMS USED? Condoms can protect you during contact between the penis, mouth, vagina, or rectum. Condoms won’t protect you from HIV or other infections unless you use them correctly. Store condoms away from too much heat, cold, or friction. Do not keep them in a wallet or a car glove compartment. Check the expiration date. Don’t use outdated condoms. Don’t open a condom package with your teeth. Be careful that your fingernails or jewelry don’t tear the condom. Body jewelry in or around your penis or vagina might also tear a condom. Use a new condom every time you have sex, or when the penis moves from the rectum to the vagina. Check the condom during sex, especially if it feels strange, to make sure it is still in place and unbroken. Do not use a male condom and a female condom at the same time. Use only water-based lubricants with latex condoms, not oil-based. The oils in Crisco, butter, baby oil, Vaseline or cold cream will make latex fall apart. Use unlubricated condoms for oral sex (most lubricants taste awful). Do not throw condoms into a toilet. They can clog plumbing. Using a Male Condom Put the condom on when your penis is erect – but before it touches your partner’s mouth, vagina, or rectum. Many couples use a condom too late, after some initial penetration. Direct genital contact can transmit some diseases. The liquid that comes out of the penis before orgasm can contain HIV. If you want, put some water-based lubricant inside the tip of the condom. If you are not circumcised, push your foreskin back before you put on a condom. This lets your foreskin move without breaking the condom. Squeeze air out of the tip of the condom to leave room for semen (cum). Unroll the rest of the condom down the penis. Do not “double bag” (use two condoms). Friction between the condoms increases the chance of breakage. After orgasm, hold the base of the condom and pull out before your penis gets soft. Be careful not to spill semen onto your partner when you throw the condom away. Using a Female Condom The female condom is a sleeve or pouch with a closed end and a larger open end. There are flexible rings at each end of the Reality condom, and a flexible v-shaped frame in the V-amour condom. Put the condom in place before your partner’s penis touches your vagina or rectum. For use in the vagina, insert the narrow end of the condom, like inserting a diaphragm. The larger end goes over the opening to the vagina to protect the outside sex organs from infection. Guide the penis into the large end to avoid unprotected contact between the penis and the partner’s rectum or vagina. Some people have used the Reality condom in the rectum after removing the smaller ring. Put the condom over your partner’s erect penis. The condom will be inserted into the rectum along with the penis. After sex, remove the condom before standing up. Twist the large end to keep the semen inside. Gently pull the condom out and throw it away. NONOXYNOL-9 Nonoxynol-9 is a chemical that kills sperm (a spermicide). It can help prevent pregnancy when it is used in the vagina along with condoms or other birth control methods. Nonoxynol-9 should not be used in the mouth or rectum. Because nonoxynol-9 kills HIV in the test tube, it was considered as a way to prevent HIV infection during sex. Unfortunately, many people are allergic to it. Their sex organs (penis, vagina, and rectum) can get irritated and develop small sores that actually make it easier for HIV infection to spread. Nonoxynol-9 should not be used as a way to prevent HIV infection. CONDOM MYTHS Condoms don’t work: Studies show condoms are 80% to 97% effective in preventing HIV transmission if they are used correctly every time you have sex. Condoms break a lot: Less than 2% of condoms break when they are used correctly: no oils with latex condoms, no double condoms, no outdated condoms. HIV can get through condoms: HIV can not get through latex or polyurethane condoms. Don’t use lambskin condoms. THE BOTTOM LINE When used correctly, condoms are the best way to prevent the spread of HIV during sexual activity. Condoms can protect the mouth, vagina or rectum from HIV-infected semen. They can protect the penis from HIV-infected vaginal fluids and blood in the mouth, vagina, or rectum. They reduce the risk of spreading other