Introduction To AIDS & HIV

WHAT DOES "AIDS"

MEAN?AIDS stands for Acquired Immune Deficiency Syndrome:
Acquired means you can get infected with it;
Immune Deficiency means a weakness in the body's system that fights diseases.
Syndrome means a group of health problems that make up a disease.
AIDS is caused by a virus called HIV, the Human Immunodeficiency Virus. If you get infected with HIV, your body will try to fight the infection. It will make "antibodies," special molecules to fight HIV.
A blood test for HIV looks for these antibodies. If you have them in your blood, it means that you have HIV infection. People who have the HIV antibodies are called "HIV-Positive. Being HIV-positive, or having HIV disease, is not the same as having AIDS. Many people are HIV-positive but don't get sick for many years. As HIV disease continues, it slowly wears down the immune system. Viruses, parasites, fungi and bacteria that usually don't cause any problems can make you very sick if your immune system is damaged. These are called "opportunistic infections

HOW DO YOU GET AIDS?
You don't actually "get" AIDS. You might get infected with HIV, and later you might develop AIDS. You can get infected with HIV from anyone who's infected, even if they don't look sick and even if they haven't tested HIV-positive yet. The blood, vaginal fluid, semen, and breast milk of people infected with HIV has enough of the virus in it to infect other people. Most people get the HIV virus by:
having sex with an infected person
sharing a needle (shooting drugs) with someone who's infected
being born when their mother is infected, or drinking the breast milk of an infected woman
Getting a transfusion of infected blood used to be a way people got AIDS, but now the blood supply is screened very carefully and the risk is extremely low.
There are no documented cases of HIV being transmitted by tears or saliva, but it is possible to be infected with HIV through oral sex or in rare cases through deep kissing, especially if you have open sores in your mouth or bleeding gums.

The Centers for Disease Control and Prevention (CDC) estimates that 1 to 1.2 million U.S. residents are living with HIV infection or AIDS; about a quarter of them do not know they have it. About 75 percent of the 40,000 new infections each year are in men, and about 25 percent in women. About half of the new infections are in Blacks, even though they make up only 12 percent of the US population. In the mid-1990s, AIDS was a leading cause of death. However, newer treatments have cut the AIDS death rate significantly

WHAT HAPPENS IF I'M HIV POSITIVE?
You might not know if you get infected by HIV. Some people get fever, headache, sore muscles and joints, stomach ache, swollen lymph glands, or a skin rash for one or two weeks. Most people think it's the flu. Some people have no symptoms.
The virus will multiply in your body for a few weeks or even months before your immune system responds. During this time, you won't test positive for HIV, but you can infect other people.
When your immune system responds, it starts to make antibodies. When this happens, you will test positive for HIV.
After the first flu-like symptoms, some people with HIV stay healthy for ten years or longer. But during this time, HIV is damaging your immune system.
One way to measure the damage to your immune system is to count your CD4 cells you have. These cells, also called "T-helper" cells, are an important part of the immune system. Healthy people have between 500 and 1,500 CD4 cells in a milliliter of blood. Without treatment, your CD4 cell count will most likely go down. You might start having signs of HIV disease like fevers, night sweats, diarrhea, or swollen lymph nodes. If you have HIV disease, these problems will last more than a few days, and probably continue for several weeks.

HOW DO I KNOW IF I HAVE AIDS?
HIV disease becomes AIDS when your immune system is seriously damaged. If you have less than 200 CD4 cells or if your CD4 percentage is less than 14%, you have AIDS. If you get an opportunistic infection, you have AIDS. There is an "official" list of these opportunistic infections put out by the Centers for Disease Control (CDC). The most common ones are:
PCP (Pneumocystis pneumonia), a lung infection;
KS (Kaposi's sarcoma), a skin cancer;
CMV (Cytomegalovirus), an infection that usually affects the eyes
Candida, a fungal infection that can cause thrush (a white film in your mouth) or infections in your throat or vagina
AIDS-related diseases also includes serious weight loss, brain tumors, and other health problems. Without treatment, these opportunistic infections can kill you.

AIDS is different in every infected person. Some people die a few months after getting infected, while others live fairly normal lives for many years, even after they "officially" have AIDS. A few HIV-positive people stay healthy for many years even without taking antiretroviral medications (ARVs).

IS THERE A CURE FOR AIDS?
There is no cure for AIDS. There are drugs that can slow down the HIV virus, and slow down the damage to your immune system. There is no way to "clear" the HIV out of your body.Other drugs can prevent or treat opportunistic infections (OIs). In most cases, these drugs work very well. The newer, stronger ARVs have also helped reduce the rates of most OIs. A few OIs, however, are still very difficult to treat.

Introduction To AIDS Treatment

Introduction to HIV and AIDS treatment.
This is the first of a set of treatment pages that give an overview of the issues surrounding HIV and AIDS treatment. It is followed by starting treatment and continuing treatment.

What is HIV antiretroviral treatment?
This is the main type of treatment for HIV or AIDS. It is not a cure, but it can stop people from becoming ill for many years. The treatment consists of drugs that have to be taken every day for the rest of someone's life. To understand more about treatment you need to have some basic knowledge of HIV and AIDS.
Antiretroviral treatment for HIV infection consists of drugs which work against HIV infection itself by slowing down the replication of HIV in the body. The drugs are often referred to as:
antiretrovirals
anti-HIV drugs
HIV antiviral drugs

What is Combination Therapy, what is HAART?
For antiretroviral treatment to be effective for a long time, it has been found that you need to take more than one antiretroviral drug at a time. This is what is known as Combination Therapy. The term Highly Active Antiretroviral Therapy (HAART) is used to describe a combination of three or more anti-HIV drugs.
When HIV replicates (makes new copies of itself) it often makes mistakes. This means that within any infected person there are many different strains of virus. Occasionally, a new strain is produced that happens to be resistant to the effects of an antiretroviral drug. If the person is not taking any other type of drug then the resistant strain is able to replicate quickly and the benefits of treatment are lost.
Taking two or more antiretrovirals at the same time vastly reduces the rate at which resistance develops.

The groups of antiretroviral drugs
There are five groups of anti-HIV drugs. Each of these groups attacks HIV in a different way.

Nucleoside/Nucleotide Reverse Transcriptase Inhibitors
The first group of antiretroviral drugs are the Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs). These were the first type of drug available to treat HIV infection in 1987. NRTIs (also known as nucleoside analogues or nukes) interfere with the action of an HIV protein called reverse transcriptase, which the virus needs to make new copies of itself. NRTIs are sometimes called the "backbone" of combination therapy because most regimens contain at least two of these drugs.
Non-Nucleoside Reverse Transcriptase Inhibitors
The second group of antiretroviral drugs are the Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs), which started to be approved in 1997. Like the nukes, NNRTIs (also known as non-nucleosides or non-nukes) stop HIV from replicating within cells by inhibiting the reverse transcriptase protein.
Protease Inhibitors
The third type of antiretrovirals is the protease inhibitor (PI) group. The first protease inhibitor was approved in 1995. Protease inhibitors, as the name says, inhibit protease, which is another protein involved in the HIV replication process.
Fusion or Entry Inhibitors
The fourth group of antiretrovirals is comprised of entry inhibitors, including fusion inhibitors. Entry inhibitors prevent HIV from entering human immune cells.
One fusion inhibitor - commonly called T-20 - has been licensed both in the US and in Europe since 2003, but only for use by people who have already tried other treatments. T-20 differs from the other antiretrovirals in that it needs to be injected (otherwise it would be digested in the stomach).
A new type of entry inhibitor known as maraviroc was licensed in 2007. This drug is known as a CCR5 inhibitor as it blocks the CCR5 co-receptor on human immune cells, preventing HIV from attaching to the cells' surface.
Integrase Inhibitors
The final group of antiretrovirals currently consists of just one drug, raltegravir, which was approved in the US in October 2007 and was introduced in the UK in January 2008. Raltegravir inhibits an enzyme called integrase, which HIV needs to insert its genetic material into human cells.

What does a combination usually consist of?
Highly Active Antiretroviral Therapy consists of a combination of three or more drugs. The most common combination given to those beginning treatment consists of two NRTIs combined with either an NNRTI or a "boosted" protease inhibitor. Ritonavir (in small doses) is the drug most commonly used to boost a protease inhibitor. An example of a common combination is the two NRTIs zidovudine and lamivudine combined with the NNRTI efavirenz.
See our drugs table for a comprehensive list of available antiretroviral drugs.
What if HAART is unavailable?
Although coverage has improved greatly in recent years, most people living with HIV in the developing world still have no access to antiretroviral treatment. Instead, the best they can hope to receive is treatment for the diseases that occur as a result of a weakened immune system, which are known as opportunistic infections. Such treatment has only short-term benefit because it does not address the underlying immune deficiency itself.
More information
Choosing when to start HIV antiretroviral treatment is a very important decision. Once treatment has begun it must be adhered to, in spite of side effects and other challenges. Many factors must be weighed up when deciding whether to begin treatment, including the results of various clinical tests. These issues are addressed in our starting HIV treatment page.

Starting antiretroviral treatment

The antiretroviral HIV drugs that are currently available can improve the quality of life of someone infected with HIV, helping them to stay well much longer than they otherwise would. The drugs slow down the replication of HIV within the body, but it must be remembered that they are a treatment and not a cure. Deciding when to start treatment can be difficult as there is no proven ‘right’ time. There are different views of the benefits of starting HIV treatment earlier or later, though most guidelines recommend not starting antiretroviral treatment until the advanced stages of HIV infection. This is an important decision with long term consequences. When to start antiretroviral treatment
There are certain tests available that will help determine when to start treatment, in particular the CD4 test and the viral load test. The CD4 Test HIV attacks a type of immune system cell called the T-helper cell. This cell carries on its surface a protein called CD4, which HIV uses to attach itself to the cell before gaining entry. The T-helper cell plays an important part in the immune system by helping to co-ordinate all the other cells to fight illnesses. A major reduction in the number of T-helper cells can have a serious effect on the immune system. HIV causes many T-helper cells to be damaged or destroyed. As a result, there are fewer cells available to help the immune system to fight illnesses. The CD4 test measures the number of T-helper cells in your blood. The more cells you have per cubic millimetre of blood, the stronger is your immune system. The stronger your immune system, the better your body can fight illnesses. A low CD4 count does not mean that you will certainly become ill, but it makes it more likely. Generally treatment is started when the CD4 test shows less than 350 T-helper cells per cubic millimetre of blood, although advice varies slightly between countries.

The Viral Load Test
Viral load refers to the amount of HIV in your blood. Like the CD4 test, the viral load test can provide important information about the likely course of HIV infection. There are different viral load tests available, which use a variety of techniques to measure the amount of virus. The results of these tests tell you whether your viral load is low, medium or high.

Opportunistic Infections
As the immune system becomes increasingly damaged by HIV it becomes susceptible to opportunistic infections. These infections would usually be fought off easily by a healthy immune system, but a low T-helper cell count means opportunistic infections such as PCP (a type of pneumonia) can be life-threatening. If one of these illnesses has become a serious problem then antiretroviral treatment may be advised straight away.

Making a decision
Viral load and CD4 tests can help you to decide whether to start treatment or not. You should talk to your doctor about the results of the tests and what they indicate. The anti-HIV drugs should reduce viral load to below the level of detection of the current tests, and the drugs should also boost CD4 levels. After considering the results of the tests, you can find out from your doctor about the various HIV drugs and combinations available, and which are suitable, including the positive and negative effects the drugs have. You should start the treatment only when you are really ready. You need to be committed, since following a drug regime can be quite demanding. Your commitment to the treatment is as important as the drugs themselves. Once the treatment is started, it is likely to be for life. So only start treatment when you feel that you can really be committed to it. In circumstances where serious opportunistic infections have occurred it is usually recommended to start anti-HIV treatment without delay.

Choosing the best combination
For most people, there are a number of drug combinations available to choose from. There are more than 20 approved drugs belonging to five different groups. It is not always easy to tell which will be the best option, since a combination that suits one person might not suit another. The first time you use antiretrovirals is when they are most effective. This is why you should try to get the combination right first time and strictly follow the guidelines on taking the therapy. It is important that the drugs can be taken properly and on time. It is therefore necessary to think ahead about the restrictions and limitations that the drugs may impose on your lifestyle. These are some of the issues that need to be considered and discussed with your doctor:

How effective is the combination?
Some combinations of antiretrovirals are more effective than others. Taking drugs randomly from the different ARV groups may result in a weak combination that doesn’t suppress the HIV infection sufficiently, ending in drug resistance. Also some anti-HIV drugs have harmful effects when used together and should not be combined (an example is stavudine and zidovudine). Always seek advice from a medical professional on the most effective combinations of ARVs.

How many pills are there and how often must they be taken?
Some combinations - especially those involving a protease inhibitor - require swallowing many pills throughout the day, which some people find hard to do. The size of the pills can also be an issue. One option for reducing the pill burden may be to take an FDC (fixed dose combination), which combines two or more drugs in a single pill, capsule or tablet.

Are there any food restrictions?
Some drugs, particularly protease inhibitors, have to be taken with food to improve absorption rates. Also some drugs impose food restrictions. There may be a need for lifestyle changes to accommodate the medication.

What are the possible side-effects?
Side effects are the undesired effects of a drug, which can range from mild irritations to serious health problems. Common side effects should be taken into consideration when choosing a combination. It is also important to consider existing medical conditions that may be worsened by some anti-HIV drugs.

Are drug interactions an issue?
When taking other drugs, food supplements or alternative therapies it's important to check with a doctor that they will not interfere with anti-HIV medication. Some substances can reduce absorption rates and so increase the risk of drug resistance developing.

Are there any special handling requirements?
Storage can be an issue as some anti-HIV drugs have to be kept below a certain temperature to last long term. Ritonavir, for example, must be refrigerated.

Preparing for adherence
The term adherence means taking the drugs exactly as prescribed, on time and following any diet restrictions. Adherence can be difficult and may require changes to your lifestyle. Developing a routine can help you to keep up with your daily treatment regime. It is important to concentrate on getting used to the treatment. Give yourself some time and space to get it to work. If the treatment instructions are not followed, it is likely that the drugs will not be absorbed properly in the body. This will have serious short- and long-term consequences. It will allow viral load to increase. It will also increase the likelihood of the HIV developing drug resistance. This will reduce the overall benefits from the drugs in the future. Issues such as side effects and frequency of dosage can compromise adherence. Contact your doctor for advice if you are having problems with adherence.

Pregnancy & treatment
Many studies have shown that anti-HIV drugs can be used during pregnancy. The drugs can be used to reduce a woman's viral load effectively below detection. This also greatly reduces the risk of the baby becoming infected. Find out more about HIV and pregnancy.

Treatment for children
Newborn children with HIV may have a significantly higher viral load than adults because their immune systems are immature. The progression of HIV in children can be rapid if not treated. Studies have shown that HAART is very effective in suppressing the virus in children, but it must be administered in the correct dosage. CD4 counts in children are generally much higher than in adults, and change with the child’s age, meaning that adult guidelines on when to start antiretroviral treatment do not apply. The progression of HIV in children is monitored through viral load and CD4 tests, as with adult treatment, but because the CD4 and viral load levels vary in children (especially between ages 1 to 4) they must be treated on an individual basis. It is harder to apply guidelines on starting treatment to children than to adults. Treatment guidelines for children differ globally; in Europe they are set by PENTA,1 and in the US by the Department of Health and Human Services.2

Issues to consider with children taking antiretroviral therapy
Adherence to treatment can be a problem because of side effects, pill burdens, swallowing difficulties, unpleasant tasting medications, or food requirements. Depending on the age of the child, adult supervision is usually needed to ensure the medication is taken consistently and correctly. Other medicines may interfere with the antiretrovirals; consult you doctor before using other medications. With younger children some medicines have to be taken as a syrup, which may require refrigeration. When a child is born with HIV, some guidelines recommend they should receive cotrimoxazole until their viral load is suppressed, to prevent opportunistic infections such as PCP. Children with tuberculosis (TB) may have to postpone antiretroviral treatment temporarily whilst taking TB treatment, as the drugs can have negative interactions. There are more antiretroviral drugs available for adults than there are for children because of the way some of them react negatively with a growing child's immune system. Children are given combination treatment based on body surface area (calculated by measuring height and weight) or sometimes on weight alone. As a child grows the dosage increases, as does the number of treatment options. Fixed-dose combinations are not recommended for children because the amounts of each drug in one tablet cannot be tailored to suit an individual. A child may at times have to take a higher dosage than an adult because their metabolism processes the drugs more quickly.

Continuing antiretroviral treatment

Continuing antiretroviral treatment

The goal of anti-HIV treatment is to reduce the amount of HIV in the body. The treatment should stop you from becoming ill for many years. Sometimes the antiretroviral therapy works without any major problems or setbacks, but sometimes there can be difficulties.
The antiretroviral drugs have not been available for very long, and despite ongoing research and development, there are some problems associated with them. Here you can find information about the issues that you may face when continuing your antiretroviral treatment.

Drug resistance
Antiretroviral drugs slow down the replication of HIV in the body. However the drugs cannot stop the replication completely, and so some HIV is able to survive despite ongoing HIV treatment.
When HIV replicates it often makes slight mistakes, so each new generation of HIV differs slightly from the one before. These tiny differences in the structure of HIV are called mutations. Some of the mutations occur in the parts of HIV which are targeted by anti-HIV drugs. So although you have some HIV that continues to be affected by the drugs, you have other strains of HIV that are not affected by the anti-HIV drugs as effectively as before. This HIV is called drug resistant HIV, and it is then able to replicate unaffected by the drugs.
When someone has drug resistant HIV (commonly referred to as drug resistance), the amount of HIV in the blood rises and the risk of the person becoming ill increases. Drug resistance is one of the main reasons why antiretroviral treatment fails. If resistance to the current drug treatment develops, this usually means that the drug regimen needs to be changed.
The viral load test can reveal developing drug resistance. Normally when anti-HIV treatment is started, the viral load drops to the undetectable level. A sign of developing resistance is if the viral load increases. In some countries, the resistance to certain drugs can be monitored by using specific resistance testing: genotypic and phenotypic testing.
Avoiding resistance
There are certain things that can be done to minimalise the risk of developing drug resistant HIV. In the first place, if the drug combination is strong then there is less risk of resistance developing. This usually means taking a combination of 3 or 4 drugs.
Regular viral load testing is also important. The viral load test can indicate if you are developing a drug resistant strain of HIV. If the drug combination is working, the viral load should be undetectable. If the viral load has increased, this can be a sign of growing drug resistance.
Taking medication exactly as prescribed is another very important part of avoiding resistance. Missing doses or not taking them on time lowers the amount of antiretroviral chemicals in your body and the virus is not properly suppressed. Then the virus is able to replicate itself faster and there is an increased risk of it becoming resistant.
Cross-resistance
Resistance to some antiretroviral drugs can limit which treatment options are available to you in the future. If HIV is resistant to one drug, it will sometimes be resistant to similar drugs in the same group. This is called cross-resistance and it means that some anti-HIV drugs will not work even though you have not used them before.
Cross-resistance is a particular problem if a person develops cross-resistance to a whole group of drugs. For example, if a person has developed a resistance to one of the non-nucleoside drugs, there is a risk that none of the other non-nucleosides will be effective.
Drug interactions
The interaction between certain anti-HIV drugs and other drugs, both pharmaceutical and recreational, can alter the effectiveness of antiretroviral therapy. The main risk is that interactions between drugs may lower the amount of anti-HIV drugs absorbed allowing low level HIV replication to occur, which may increase risk of drug resistance.1 If you are taking drugs other than prescribed anti-HIV therapy, always read the instructions or consult your doctor.
Pharmaceutical drugs for treating opportunistic infections are among those that may have undesirable interactions with antiretroviral medication, for example the tuberculosis treatment rifabutin should usually not be used with the protease inhibitor saquinavir or the NNRTI delavirdine.2
Interactions between recreational and antiretroviral drugs have resulted in several deaths in recent years because of the potentiation (boosting) effects that antiretrovirals have on the recreational drugs. Minimal solid research has been carried out in this area and little is known about how the body processes recreational drugs. The safest action is not to mix these drugs with antiretrovirals at all. AVERT has more information about recreational drug interactions with ARV treatment.
Side effects
Drugs are generally licensed and tested to treat specific illnesses. What are referred to as side effects happen when the drugs affect the body in ways other than those intended. Most of the anti-HIV drugs have known side effects, but this does not mean that everyone who takes them will experience side effects. Generally, you cannot predict if you are likely to experience side effects or not. Some people only experience the side effects mildly and find them easily manageable. But for some people the side effects occur so strongly that they have to consider other alternative drugs.
The most common side effects are nausea and feeling tired. Side effects are often referred to by the grade of the effect, and the grades range from mild to moderate to severe to life-threatening. For example, it is considered a mild side effect if a person has 2-3 vomiting episodes a day. Life-threatening side effects such as extreme limitations in daily activity and hospitalisation are rare, but are still threats to some.3
When drugs are developed they go through clinical trials. A clinical trial is a study with people to test how well the new drugs or treatment works and how safe it is. Some long-term side effects may not be noticed in the clinical trials. It is hard for the researchers to draw consistent information on side effects in clinical trials, since people have different treatment histories, general health and tolerability levels. Therefore, some side effects only become apparent after the drugs have been approved and have been used by more people over a longer period.
Since HIV is a life-threatening infection, there is a constant need for new drugs. Sometimes it is important to get a drug on the market despite known side effects. Many patients and health professionals agree that the anti-HIV drugs are far from perfect and the tolerability and side effects of the drugs need to be vastly improved.
It can be useful to find out about the possible side effects that particular drugs have, before you start anti-HIV treatment. The side effects often get better after you have been on the treatment for a little while, as the body then starts to adjust to the anti-HIV drugs. Your doctor might be able to give you some treatment to help with the most common side effects such as nausea and diarrhoea. Some people use alternative therapies and medications with the combination therapy to ease the side effects. For example, some people find taking peppermint eases their feeling of nausea. Sometimes the side effects do not diminish over time, and in some instances one or more of the drugs in the combination can be changed to reduce the side effects. If you feel that the side effects are too much to cope with, you should always seek help from your doctor before changing or stopping your regimen.
Adherence
The term adherence means taking the drugs exactly as described. This includes taking all of the medication at the right time; ensuring that there will be no interactions with other drugs being taken; and taking the medication with or without food, as the medication directions state.
Anything below 95 percent adherence has been associated with increases in viral load and drug resistance. Therefore, adherence to anti-HIV treatment is extremely important. This means missing no more than one dose a month, if taking antiretroviral drug treatment once a day.
Often experiencing side effects makes adherence difficult. As adherence is such a vital part of treatment, it is important to monitor closely the impact that side effects have on your adherence. If side effects are affecting adherence or if you are finding it difficult to stick to your drug regimen for any reason, you must tell your doctor.
Changing HIV treatment
A drug combination can fail for a number of reasons including:
The combination of drugs was not strong enough
The drugs were not absorbed properly by the body
Drug resistance
Strong side effects
Poor adherence.
There are two main reasons why anti-HIV treatment sometimes needs to be changed.
Firstly, a change of treatment is needed when the antiretrovirals fail to work and slow down the replication of the virus in the body. Increased viral load or an HIV-related illness are signs of failing anti-HIV treatment.
Secondly, sometimes side effects are so strong, intolerable and even life-threatening that the treatment must be changed.
Monitoring the viral load carefully is an important part of treatment. There are different opinions about the 'right time' to change the treatment if your viral load is rising. Some doctors recommend changing the treatment as soon as the viral load starts to rise. Others recommend monitoring the overall trend of the viral load before making a decision to change. Changing the drugs earlier rather than later could mean running out of treatment options more quickly. But changing later means there is a danger of developing resistance to certain drugs. This can seriously limit your future treatment options. The changes that can be made to the drug regimen will depend on the drugs already being used, the CD4 count and your general health.
Antiretroviral drugs work best when used the first time. This is one of the reasons why it has to be considered carefully whether a change of treatment is necessary or not. The combination of anti-HIV drugs other than the first or second treatment is called salvage therapy. It is also referred as second-line, third-line or rescue therapy.
Many people start their salvage therapy with much higher levels of viral load than when they started previous HIV treatments. This puts more pressure on the new combination to work. Each combination used lessens the chance of maintaining a low viral load because of the possibility of developing resistance to the drugs. The choice of new treatment should always depend on what caused the previous one to fail.
If you have an increased viral load, strong side effects or need to change your anti-HIV treatment for any other reasons then always contact your doctor before taking any action.
Immune Reconstitution Inflammatory Syndrome (IRIS)
IRIS is an illness that occurs within a minority of patients during the first few months of HAART. It is caused by an excessive response by the recovering immune system against opportunistic infections that were already present, but were previously dormant and not producing symptoms. IRIS does not indicate that treatment is failing. Usually the best response to IRIS is to continue treatment; the symptoms should then go away within a few weeks. In cases involving severe opportunistic infections, such as cryptococcal meningitis or tuberculosis, it may be necessary to stop HAART whilst the infection is treated.
The incidence of IRIS is estimated at 10% of all patients starting HAART, and up to 25% among patients starting treatment with a CD4 cell count below 50 cells per cubic millimetre.
Structured Treatment Interruptions (STIs)
A Structured Treatment Interruption (STI) or drug holiday is when someone stops taking anti-HIV treatment temporarily. People take treatment interruptions for a variety of reasons, such as side effects, ineffectiveness of the drugs and psychological issues. STI does not mean skipping or stopping your medication randomly, but taking a break from your drug regimen with a planned timescale, close monitoring and help from your doctor.
In theory, STIs can have benefits such as reducing toxicity, improving quality of life and lowering the cost of medication. Enjoying a drug-free period may also have some psychological benefits such as increased adherence when returning to HIV treatment.
In recent years a series of studies have cast doubt on the safety of STIs. The most important of these was an investigation known as the SMART trial, which involved more than 5,000 patients in 33 countries. Volunteers in the SMART trial were randomly assigned to two groups. Members of the first group took treatment continuously, while the others took treatment only at times when their CD4 counts were very low. The SMART trial was ended in early 2006 because patients in the treatment interruption group were significantly more likely to fall ill or die.4
The main risks of taking a treatment break are that the viral load will rise and the CD4 count will drop, increasing the risk of illness. Also, stopping and restarting the treatment can make it easier for the virus to develop resistance to the anti-HIV drugs. This is because some of the drugs remain in the body longer than others, so if a treatment interruption is not carefully managed then it can result in temporary "monotherapy", which makes it much easier for the virus to develop resistance.
The results of the SMART trial do not necessarily mean that all STIs are unsafe. Some studies have suggested that other types of STI might be as effective as continuous treatment in certain circumstances, though the evidence is not yet conclusive. If you are considering a treatment interruption or stopping your treatment then always talk to your doctor first. Taking unsupervised treatment breaks can do more harm than good to your health and can limit your future treatment options.
The need for safer sex
Unprotected sex puts both you and your partner at risk. HAART suppresses HIV but it hasn't been proven to stop transmission, even when the viral load is undetectable. Unprotected sex between two HIV positive people is not a risk-free activity; there are many different strains of HIV and it is possible to become infected more than once, which can complicate treatment. People on HAART should take as much care to minimise the risk of HIV transmission as they did before starting anti-HIV treatment.