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HIV-Related Infections and Cancers: Entire Lesson

for Veterans and the Public

HIV-Related Infections and Cancers: Entire Lesson

Common opportunistic infections and HIV-related cancers

Opportunistic infections (OIs) can be caused by viruses, bacteria, fungus, even parasites. Common OIs that are covered in this tutorial are:

  • Anal cancer
  • Candidiasis (thrush)
  • Coccidioidomycosis
  • Cryptococcosis
  • Cryptosporidiosis
  • Cytomegalovirus
  • Herpes simplex
  • Herpes zoster (shingles)
  • Histoplasmosis
  • HIV-related neurocognitive disorders
  • HIV wasting syndrome
  • Isosporiasis
  • MAC
  • PCP
  • Pneumonia
  • PML
  • Salmonella
  • Toxoplasmosis
  • Tuberculosis

AIDS-related cancers:

  • Cervical cancer
  • Kaposi sarcoma
  • Lymphomas

What follows are descriptions of some of these illnesses. Note that most of them occur only in people with severely suppressed immune function, such as in advanced HIV infection.

Candidiasis (thrush)

Candidiasis (or thrush) is a fungal infection of the mouth, esophagus and/or vagina. Most people already have the Candida fungus in their body, but the body keeps it in check. Someone whose immune system is weakened is more likely to develop problems.

Some people show no symptoms, but for those who have them, symptoms can include:

  • white patches on the tongue
  • smooth red areas on the back of the tongue
  • painful areas in the mouth
  • changes in taste
  • sensitivity to spicy foods
  • decreased appetite
  • pain or difficulty swallowing
  • yeast infection of the vagina (vaginal itching and white discharge)

Treatments for thrush include liquid medicines (suspensions) that you swish around in your mouth and swallow as well as antifungal pills. If you are taking drugs for oral thrush, be sure to:

  • brush your teeth after each meal;
  • rinse your mouth of all food before using either lozenges or oral suspension;
  • avoid hurting your mouth: use a soft toothbrush, avoid foods and drinks that are too hot or too spicy.

Cervical cancer (for women)

Cervical cancer usually is caused by the same virus that causes anal and genital warts. The virus is called human papilloma virus (HPV). Using condoms consistently may help reduce the risk of this infection.

In the early stage, there usually are no symptoms. Some women, however, may notice bleeding between their periods or spots of blood after sex. Women should get regular exams and Pap tests to check for cervical cancer and precursors to cancer.


This is a caused by a fungus present in soil in desert areas of Mexico and South America and in the southwestern United States, but risk of infection is highest in Kern and Tulare counties and the San Joaquin Valley in California.

The fungus is inhaled from dust and dirt carried in the air or wind, rather than passed from person to person. Most people don't have symptoms. Others will feel like they have the flu, sometimes with chest pain and a cough. Infection can lead to meningitis, including headache, fever, and altered mental states.

Treatment with antifungal drugs usually is given for a long period of time and sometimes for life. Sometimes surgery is required to remove infected tissue. The seriousness of the disease depends on what part or parts of the body the fungus has infected.


This fungus is present in soil, usually where there are bird droppings, particularly those of pigeons. It can be passed through the air or wind. It's important to avoid handling birds, including pet birds, and to avoid areas with lots of bird droppings.

The fungus can infect different organs, such as the lung, heart, and central nervous system. Symptoms vary, depending on where the infection occurs. In the lung, for example, symptoms can include:

  • cough
  • fever
  • malaise
  • shortness of breath

This infection is very serious. It can lead to meningitis (infection around the brain) and pneumonia. Drugs are available to treat this infection, and they must be continued until the immune system has improved on HIV medications.


This parasite is found in the feces of many animals, including humans. It can contaminate drinking water.

To avoid infection from people, avoid contact with feces (diapers, sex involving direct oral-anal contact). Try to avoid accidentally swallowing water when swimming in pools, rivers, or lakes. Do not drink from streams. Drink bottled water or use filters on tap water (look for "submicron" filters, which will filter out this parasite). Avoid eating raw oysters because they can carry eggs of cryptosporidia.

Symptoms of this infection include:

  • persistent watery diarrhea
  • nausea
  • vomiting
  • abdominal pain
  • cramping
  • loss of appetite
  • weight loss

The main treatment for cryptosporidiosis is effective HIV antiretroviral medications. In conjunction with HIV medications, antimicrobials can hasten clearance and improve resolution of diarrhea. No medication has been shown to cure cryptosporidiosis in the absence of HIV medications.

Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is transmitted by close contact through sex and through saliva, urine, and other body fluids. It can be passed from mother to child during pregnancy and by breast-feeding. If you are not infected, using condoms during sex may help prevent infection.

Many people are infected with this virus, though they have no symptoms. In people with HIV who have low CD4 counts, the infection can be extremely serious. Symptoms can include:

  • blind spots in vision, loss of peripheral vision
  • headache, difficulty concentrating, sleepiness
  • mouth ulcers
  • pain in the abdomen, bloody diarrhea
  • fever, fatigue, weight loss
  • shortness of breath
  • lower back pain
  • confusion, apathy, withdrawal, personality changes

Drugs are available to keep symptoms of the infection under control. HIV drugs can improve the condition, too. If you have CMV and haven't started taking drugs for HIV, it may be best to wait until you have been on treatment for CMV for a few weeks.

Treatment can prevent further loss of vision but cannot reverse existing damage. If you experience any vision problems, tell your provider immediately.

Herpes simplex virus

Herpes simplex is common in many people, but in people with HIV outbreaks may be more frequent or more severe. Symptoms include outbreaks of red, painful sores on the mouth ("fever blisters"), genitals, or anal area. Genital herpes is passed through sexual contact. Herpes on the mouth is easily spread through kissing, and it can be spread to the genitals through oral sex. Although less common, the virus can be spread even if you don't have blisters. Using latex barrier protection during sex can decrease the risk of infection.

Drugs are available to help herpes blisters heal, but there's no cure. Outbreaks may occur periodically for the rest of your life. Taking an anti-herpes medication every day can help reduce the number of outbreaks.

For more information on herpes, call the National Herpes Hotline at 919-361-8488.

Herpes zoster (shingles)

Shingles is caused by the varicella-zoster virus, the same virus that causes chickenpox. People with shingles usually had chickenpox as a child. Shingles is caused by reactivation of the virus.

Symptoms can include:

  • painful skin blisters on one side of the face or body
  • vision loss

The skin blisters can be extremely painful. Treatment can help the blisters heal, but there is no cure of the underlying infection, which stays dormant in the body and can reactivate. Shingles can cause painful nerve inflammation that persists after the skin rash has healed. Early treatment can help reduce the likelihood of long-term nerve pain. Antibiotic ointments can help keep the infection from becoming super-infected. The skin rash should be kept covered until healed in order to prevent spreading the infection to anyone who is not immune to the virus. A vaccine to prevent shingles is available for certain groups of patients — check with your VA provider to see if you should receive this vaccine.


This infection is caused by a fungus present in soil contaminated with bat or bird droppings, particularly in eastern and central United States as well as in Mexico. It gets into the air when the soil is disturbed, such as when people explore caves. It is not passed from person to person.

Symptoms can include:

  • fever
  • weight loss
  • cough
  • shortness of breath
  • abdominal pain

Histoplasmosis can be quite serious but is treatable with medications, which need to be continued until the immune system has improved with HIV treatment. In some parts of the country, medication is given to patients with HIV who have low CD4 counts in order to prevent histoplasmosis.

HIV-associated neurocognitive disorders

HIV can invade the brain and cause a variety of symptoms. Sometimes this disease is called "HIV encephalopathy" or "AIDS dementia" when the symptoms are severe. It is most common in people who are not on effective HIV medications and when the CD4 cell count is very low.

Symptoms can include:

  • memory loss
  • depressed mood
  • personality changes
  • apathy
  • unsteadiness when walking
  • irritability
  • clumsiness
  • shaky hands (poor handwriting)

This condition is less common with early and continuous treatment of HIV, but less severe forms of cognitive disease are increasingly recognized.

People who are affected need to have a strong support system. Friends, roommates, or family members can help make sure that HIV medications are taken on time, in the right combination, and at the right dose. If memory is poor, a person can use notes, calendars, and alarms to remember medicines, appointments, and other important events.

HIV wasting syndrome

Wasting syndrome refers to unwanted weight loss of more than 10 percent of a person's body weight, with either diarrhea or weakness and fever that have lasted at least 30 days. For a 150-pound man, this means a weight loss of 15 pounds or more. Weight loss can result in loss of both fat and muscle. Once lost, the weight is difficult to regain.

The condition may occur in people with advanced HIV disease, and can be caused by many things: HIV, inflammation, or opportunistic infections. The person may get full easily or have no appetite at all.

The most important treatment for wasting syndrome is effective treatment of HIV with antiretroviral medications. In addition, the condition may be controlled, to some degree, by eating a good diet. A "good diet" for a person with HIV may not be the low-fat, low-calorie diet recommended for healthy people. Compared with other people, you may need to take in more calories and protein to keep from losing muscle mass. To do this, you can add to your meals:

  • peanut butter
  • legumes (dried beans and peas)
  • cheeses
  • eggs
  • instant breakfast drinks
  • milkshakes
  • sauces

You can also maintain or increase muscle mass through exercise, especially with progressive strength-building exercises. These include resistance and weight-lifting exercise. (For more diet and exercise tips, see the Living with HIV section.)


This condition is caused by a parasite found in feces. It may contaminate food or drinking water. It is most common in tropical and subtropical regions of the United States. To avoid infection, do not drink water from rivers and streams. When appropriate, drink bottled water or use filters on tap water. Cook food thoroughly.

Symptoms can include:

  • stomach cramps
  • watery diarrhea
  • weight loss (which may be significant)
  • weakness
  • loss of appetite
  • fever

Rehydration and nutritional support are key components of treatment. Antiparasitic drugs can treat the infection, but they may need to be taken for a long time to keep the parasite in check.

Kaposi sarcoma

Kaposi sarcoma (KS) is the most common cancer seen in HIV. This cancer is caused by the human herpes virus 8 (HHV-8), also known as Kaposi sarcoma-associated herpesvirus (KSHV). The virus can be spread by deep kissing, unprotected sex, and sharing needles. It also can be spread from mother to child. However, HIV-related KS usually develops only in people with relatively advanced HIV disease.

Symptoms include brown, purple, or pink lesions (or blotches) on the skin, usually on the arms and legs, neck or head, and sometimes in the mouth. KS can also affect the lungs and intestines and cause swelling in the legs. Sometimes there is tooth pain or tooth loss, weight loss, night sweats, or fever for longer than 2 weeks.

HIV drugs can slow the growth of lesions, and even reverse the condition itself. KS has become less common and much more treatable since the development of effective HIV therapy. Other treatments for KS, such as laser therapy, are meant to relieve symptoms and improve the appearance of the lesions. There is also chemotherapy that helps control KS.


Lymphomas associated with HIV include a large group of cancers that begin in the cells of the immune system. The cancers can spread to different parts of the body, such as the central nervous system, liver, bone marrow, and gastrointestinal tract. Symptoms depend on where the cancer resides.

Treatment varies depending on the specific cancer but can include radiation and chemotherapy. HIV medications help boost the immune system and aid the body in fighting the cancer. In fact, the development of effective combination HIV therapy has greatly improved the outlook for persons with HIV-associated lymphoma.

Mycobacterium avium complex (MAC)

This condition is caused by bacteria that are present everywhere in the environment — in soil, food, and animals. It is difficult to avoid exposure because MAC is in so many places, but MAC usually causes illness only in people with very weakened immune systems, like those with advanced HIV disease.

Symptoms of MAC can include:

  • fever
  • night sweats
  • weight loss
  • loss of appetite
  • chronic diarrhea
  • weakness
  • fatigue
  • abdominal pain

HIV drugs, by helping your immune system stay strong, can help your body fight the infection. Antibiotics given over a long period of time can control the infection and may be stopped once the disease is cured and the immune system is strong enough. Call your provider if you have vision changes or abdominal discomfort while being treated for MAC.

Pneumocystis pneumonia (PCP)

Pneumocystis pneumonia (PCP) is a serious infection caused by the fungus Pneumocystis jirovecii. PCP usually occurs in persons with a CD4 count of less than 200 cells per cubic millimeter of blood. Starting combination antiretroviral therapy before your CD4 count gets this low, or, if you already have a CD4 count of less than 200, taking daily doses of protective antibiotics, greatly reduces the risk of developing PCP. The fungus can affect many organs, the most common being the lung.

Symptoms can include:

  • fever
  • shortness of breath
  • dry cough
  • night sweats or fatigue

The usual treatment is with antibiotics.

After completing treatment, if you experience shortness of breath (especially with exercise), fever, chills and sweats, or a new cough, contact your provider.

Pneumonia, recurrent

Bacterial pneumonia (often caused by Streptococcus pneumoniae or Haemophilus influenzae) can affect people whose immune systems are not weakened by HIV. Persons infected with HIV, however, are much more likely than people who are HIV /negative to develop bacterial pneumonia. Fortunately, these pneumonias can be treated with available antibiotics. Persons with HIV should receive vaccines to help prevent infections caused by Streptococcus pneumoniae. Contact your provider for more information.

Progressive multifocal leukoencephalopathy (PML)

This disease is caused by a virus called the JC (John Cunningham) virus. This is a common virus and most people probably are infected early in life. However, in people with HIV the virus can cause serious disease. The virus is possibly spread through sexual contact, or from mother to child.

Symptoms can include:

  • difficulty in speaking
  • difficulty in walking
  • weakness in arms or legs
  • personality changes
  • seizures
  • changes in vision
  • headache
  • shaky hands

There is no specific treatment for PML, but HIV therapy can reverse the symptoms and keep the JC virus under control. People with PML should have a good support system. Friends, roommates, or family members can help make sure that HIV medications are taken on time, in the right combination, and at the right dose. The disease is extremely serious and can lead to death.

Salmonella septicemia, recurrent

Salmonella is a bacteria often found in food such as undercooked poultry, eggs, and unpasteurized milk. It is also present in water, soil, kitchen surfaces, animal feces, and raw meat and on certain animals, such as reptiles. Because of the risk of salmonella, reptiles are not recommended as pets for patients with HIV, especially if their immune suppression is advanced.

Symptoms can include:

  • diarrhea
  • fever

Salmonella septicemia usually is treated with antibiotics. Drug therapy may be required for life to prevent relapses.


The parasite that causes toxoplasmosis is found in almost all animals. Cats and birds are major sources of infection. Indoor cats pose less risk. Avoid cat feces (use gloves to change litter). Avoid handling birds. Never eat undercooked meats, particularly pork or lamb, or unwashed vegetables.

Symptoms can include:

  • dull, constant headache
  • changes in vision
  • disorientation
  • seizures

Toxoplasmosis can occur in people with advanced immune system disease caused by HIV. It can be treated with antibiotics, which need to be continued until the immune system improves through HIV (antiretroviral) therapy. If you are being treated for toxoplasmosis, see your provider promptly if your symptoms worsen or you develop a rash.

Tuberculosis (TB)

Mycobacterium tuberculosis disease is caused by a bacteria passed through the -air when someone with TB infection coughs, sneezes, or talks. It is spread easily in closed-in places, such as low-income housing, shelters, and jails.

Tuberculosis (TB) can occur at any time in the course of HIV infection, but most often when CD4 counts are low. Symptoms can include fever, night sweats, weight loss, fatigue, loss of appetite, and coughing.

TB can be prevented and usually is curable. If you have TB, it's important that you take your TB medication exactly as prescribed (missed doses can result in the TB germ developing resistance to the drug). Some TB medications can damage your liver, but your liver usually recovers if the medications are stopped. If your skin or eyes turn yellow, or if your urine darkens to the color of Coca-Cola while you are taking tuberculosis medications, call your provider immediately. It could be a sign of liver damage.

Many people who are exposed to TB do not develop active tuberculosis but have a small amount of TB in the body. If your provider diagnoses you with exposure to TB but not active TB, they will recommend treatment to reduce the likelihood of developing active disease.

CD4 counts and infections

CD4 cells (also known as CD4+ T cells) are white blood cells that fight infection. CD4 cell count is an indicator of immune function and disease progression and one of the key determinants for the need of opportunistic infection (OI) prophylaxis. CD4 cell counts are obtained from bloodwork as part of laboratory monitoring for HIV infection.

Studies have shown that starting HIV medicines soon after you are diagnosed, and ideally when your CD4 cell count is high, will greatly help your health and will reduce the risk of OIs. Regularly checking your CD4 cell count will allow you to begin necessary prophylactic medications to reduce your risk of opportunistic infections.

AIDS-defining illnesses

Certain serious and life-threatening diseases that occur in HIV-positive people are called "AIDS-defining" illnesses. When a person gets one of these illnesses, he or she is diagnosed with the advanced stage of HIV infection known as AIDS.

The Centers for Disease Control and Prevention (CDC) has developed a list of these illnesses (see below). No single patient is likely to have all of these problems. Some of the conditions, in fact, are rare.

  • Candidiasis of the esophagus, bronchi, trachea, or lungs [(but NOT the mouth (thrush)]
  • Cervical cancer, invasive
  • Coccidioidomycosis, disseminated or extrapulmonary
  • Cryptococcosis, extrapulmonary
  • Cryptosporidiosis, chronic intestinal (greater than one month's duration)
  • Cytomegalovirus disease or CMV (other than liver, spleen, or nodes)
  • Cytomegalovirus retinitis (with loss of vision)
  • Encephalopathy, HIV related
  • Herpes simplex: chronic ulcer(s) (more than 1 month in duration); or bronchitis, pneumonitis, or esophagitis
  • Histoplasmosis, disseminated or extrapulmonary
  • Isosporiasis, chronic intestinal (more than 1 month in duration)
  • Kaposi sarcoma
  • Lymphoma, Burkitt's (or equivalent term)
  • Lymphoma, immunoblastic (or equivalent term)
  • Lymphoma, primary, of brain
  • Mycobacterium avium complex or M kansasii, disseminated or extrapulmonary
  • Mycobacterium tuberculosis, any site (pulmonary or extrapulmonary)
  • Mycobacterium, other species or unidentified species, disseminated or extrapulmonary
  • Pneumocystis pneumonia (PCP)
  • Pneumonia, recurrent
  • Progressive multifocal leukoencephalopathy
  • Salmonella septicemia, recurrent
  • Toxoplasmosis of brain
  • Wasting syndrome due to HIV

(Source: Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. Morbidity and Mortality Weekly Report, December 18, 1992/41 (RR-17), 1993).

Preventing Opportunistic Infections (OIs)

Opportunistic infections can be caused by viruses, bacteria, and fungus, even parasites. One way to avoid these infections is to reduce your risk of exposure to these germs. Here are some practical suggestions.

Sexual exposures

  • Use condoms every time you have sex. (See Tips for Using Condoms)
  • Avoid oral-anal sex.
  • Use waterproof gloves if you're going to insert your finger into your partner's anus.
  • Frequently wash hands and genitals with warm soapy water after any sex play that brings them in contact with feces.

Injection drug use

  • Do not inject drugs.
  • If you cannot stop using, avoid sharing needles and other equipment.
  • Get vaccinated against hepatitis A and hepatitis B.

Job exposure

Certain type of jobs or facilities can put a person with HIV at risk of OIs. These include work in:

  • health care facilities
  • homeless shelters
  • day-care centers
  • prisons
  • places that involved work with animals (such as farms, veterinary clinics, pet stores)

Pet exposure

Pets can carry diseases that don't affect a healthy person but can pose a serious risk to someone with HIV. For that reason, if you have a pet, follow these suggestions.

  • Wash your hands after handling your pet (especially before eating).
  • Avoid contact with your pet's feces. If your pet has diarrhea, ask a friend or family member to take care of it.
  • If you are getting a new pet, try not to get one that is younger than a year old, especially if it has diarrhea. (Young animals are more likely to carry certain germs like Salmonella.) Avoid stray animals.
  • Keep your cat indoors. It should not be allowed to hunt and should not be fed raw or undercooked meat.
  • Clean the litter box daily. If you do it yourself, wear gloves and wash your hands thoroughly afterward.
  • Control fleas (ask your vet how to do this).
  • Avoid playing with your cat in ways that may result in scratches or bites. If you do get scratched or bitten, wash the area right away. Don't let your cat lick your cuts or wounds.
  • Avoid areas where there are any bird droppings. Do not disturb soil underneath bird-roosting sites.
  • Avoid touching reptiles, such as snakes, lizards, iguanas, and turtles.
  • Wear gloves if you are cleaning an aquarium.

Cautions about food and water

  • Avoid raw or undercooked eggs (including hollandaise sauce, Caesar salad dressing, some mayonnaises, eggnog, cake and cookie batter).
  • Avoid raw or undercooked poultry, meat, and seafood (especially raw seafood). Use a meat thermometer. Cook poultry to 180° F, and other meats to 165° F. If you don't have a meat thermometer, cook meat until no traces of pink remain.
  • Avoid unpasteurized dairy products and fruit juice.
  • Avoid raw seed sprouts (such as alfalfa, mung beans).
  • Thoroughly wash fruits and vegetables before eating.
  • Don't let uncooked meats come into contact with other uncooked foods. (Wash thoroughly hands, cutting boards, counters, knives, and other utensils after contact with uncooked meats.)
  • Do not drink water directly from lakes or rivers. Filtered water is preferable, particularly if your immune system is weak.

People with HIV whose immune systems are severely weakened may want to:

  • Avoid soft cheeses (feta, brie, camembert, blue-veined, and Mexican-style cheeses, such as queso fresco).
  • Cook leftover foods or ready-to-eat foods, such as hot dogs, until they are steaming hot.
  • Avoid food from delicatessens, such as prepared meats, salads, and cheeses--or heat these foods until steaming before eating.

Cautions about travel

Before you travel to other countries, particularly developing countries, talk to your provider about ways you can avoid getting sick on your trip. People with weakened immune systems are at risk and should discuss travel plans well in advance. Be sure to check with your provider regarding recommended or required immunizations, as well as indications and precautions of travel vaccines, before traveling out of the country.

When traveling in developing countries, people who have HIV should be especially cautious of food and water that may be contaminated. It is best to avoid:

  • raw fruits and vegetables (unless you peel them first)
  • raw or undercooked seafood or meat
  • tap water or ice made with tap water (drink bottled water instead)
  • unpasteurized milk or dairy products
  • swallowing water when swimming

Talk to your health care provider about whether you need to get vaccinated before your trip and whether you need to take drugs to prevent diseases that are common in the country you are going to visit.

Just Diagnosed Resources

  • Questions to Ask Your Provider about Your HIV Diagnosis
    A list of questions to print out and bring to your medical appointment.
  • Just Diagnosed with HIV?Link will take you outside the VA website. VA is not responsible for the content of the linked site.
    The Body's starting place for people newly diagnosed with HIV. Articles on understanding HIV, first steps to treatment, telling others.
  • The CDC National HIV Hotline, including its Spanish Service and TTY Service:
    1‑800‑CDC‑INFO (1‑800‑232‑4636), 8 am - 8 pm ET, Monday through Friday.
More Information:

Find websites on more specific topics, such as opportunistic infections, travel health, and more.