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Opportunistic Infections 101

The Stalker Awaits

September/October 2001

A note from The field of medicine is constantly evolving. As a result, parts of this article may be outdated. Please keep this in mind, and be sure to visit other parts of our site for more recent information!

An opportunist: someone who takes advantage of you. Well, that's what an opportunistic infection is -- one that waits until your immune system is weak so it can prey on you. Specific microorganisms that normally live in a peaceful co-existence can potentially overcome the body when the immune system is failing. In fact, getting some of these illnesses gives you an AIDS diagnosis.

The problem today with opportunistic infections (OIs) is that so many people, especially people of color, are unaware of their HIV infection until they are hit with a serious disease. The U.S. Centers for Disease Control and Prevention (CDC) estimates that one out of four people with HIV in this country are unaware of their infection. The good news is that many OIs can be averted with prevention medicines, also called "prophylaxis."

PCP (Pneumocystis Carinii Pneumonia)

Formerly thought to be caused by a parasite, Pneumocystis carinii is now recognized as a fungus. It's present in almost all people from childhood. PCP generally occurs when T-cells fall below 200.

Transmission: None. Exposure to someone with PCP will not trigger PCP in you.

Symptoms: Persistent dry cough (more than two weeks), shortness of breath or difficulty breathing on exertion, fevers, chills, sweats, and increasing fatigue. Cough may produce thin, clear mucus.

Prevention: Everyone with less than 200 T-cells should take prophylaxis (preventative medicine), as well as people with a prior history of PCP and those with thrush and persistent fevers. Fortunately, prevention medications are very inexpensive. Taken at night, prophylaxis can help with the sun sensitivity often caused by TMP-SMX (brand names Bactrim, Septra). The daily double-strength medication also protects against toxoplasmosis and some common respiratory bacterial infections. People with severe reactions can discontinue until they get better, then go back on at lower doses until their tolerance builds up. People who once had less than 200 T-cells may discontinue prophylaxis when they have more than 200 T-cells for three to six months with HIV therapy.

Candidiasis (Thrush)

Usually the first OI to appear, and certainly the most common. Although there's a very low mortality rate for thrush, its often painful oral presence can lead to a decrease in eating and therefore, nutritional intake, with the potential for escalating complications such as wasting, which is life-threatening. Lots of sugar, alcohol, caffeine and carbohydrates (like bread and pasta) promote thrush. Stress and lack of rest encourages fungus growth.

Transmission: None, although very rare cases of person-to-person transmission have been documented.

Symptoms: Causes fuzzy white or pinkish-red patches in the mouth and esophagus (feeding tube down the throat). Burning, altered taste sensation (especially when eating spicy or sweet food), and difficulty swallowing and eating. Also, because food can get stuck in the esophagus, people with candida esophagitis have chest discomfort when eating. Thick white discharge in the vagina, plus itchiness, rash, and burning sensation.

Prevention: Not recommended due to the low mortality rate of the disease, the cost of prophylaxis and the potential for developing resistance to it. Also, treatment is usually effective if thrush does develop. Interventions include smoking cessation, good oral hygiene, and avoiding both unnecessary antibiotics and use of corticosteroids. Additionally, diabetics tend to have thrush because of its tendency to live off sugar, so if you're diabetic, watch your sugar intake and keep blood glucose (sugar) levels under control. Vaginal thrush is associated with high-estrogen oral contraceptives, pregnancy, diabetes, tight-fitting pants, deodorant tampons and deodorant sprays, douches, intestinal parasites, sexually transmitted diseases, and antibiotics (ironically, some of which are used to treat other vaginal conditions).

Hepatitis C Virus (HCV)

A virus that infects the liver. Now considered an OI because people with HIV are seven times more likely to die from it than people who are HIV-negative. [See "HCV/HIV Co-Infection: A Patient's Perspective"]

Transmission: Blood-to-blood contact, including the sharing of straws for snorting cocaine, and sexual contact. Injection drug users should avoid sharing equipment, including water and cookers, or sterilize the equipment that they can clean. Estimated to be present in 85% of current or former injection drug users. Can be transmitted at birth from an infected mother. May possibly be transmitted through unprotected sex, infected instruments during tattooing or body piercing, and by using the razor or toothbrush of an infected person.

Symptoms: May cause no symptoms until liver damage occurs. Then causes flu-like symptoms such as nausea, fatigue, and headache.

Prevention: Infusion during labor. Bleaching syringes. Syringe exchange programs. Use of either new needles or of an autoclave for sterilizing needles by tattoo artists and body piercers. People with HCV should be vaccinated against hepatitis A. They should also avoid "excessive amounts of alcohol" to prevent serious liver damage, although it is unclear if even 12 ounces of beer a week can increase the risk of cirrhosis (scarring of the liver).

Tuberculosis (TB)

A disease of the lungs that can spread to other organs. Risk of TB increases 100 times with HIV infection. It generally occurs in HIV-positive people when they have between 200 and 300 T-cells. Also, heavy drinkers, injection drug users and people who are very underweight are at higher risk.

Transmission: Through the air by coughing and sneezing.

Symptoms: Productive coughing (producing phlegm), chest pain, fever, fatigue, night sweats, weight loss and the spitting of blood.

Prevention: Upon HIV diagnosis, undergo a tuberculin skin test (TST). If positive, or if you have symptoms, undergo a chest radiography and doctor's evaluation to look for active TB. If no TB is found but the TST is positive, take preventative medicine for either two months or nine months. (See the OI guidelines for TB drugs that cannot be taken with HIV antivirals.) Also avoid places thought to be high-risk, such as volunteer work or employment in prisons, homeless shelters and health clinics (believe it or not), but always consult your healthcare provider.

Human Herpesvirus 8 (HHV-8)

The virus associated with Kaposi's sarcoma (KS). Kaposi's sarcoma is a rare cancer that is generally benign but sometimes disfiguring. It can cause purplish or brownish marks on the skin and sometimes spreads to cause disease in the organs. Most commonly occurs in men.

Transmission: Seems to be sexually transmitted, including during deep kissing. Research has found greater amounts of the virus in saliva than in semen.

Prevention: HAART that successfully lowers viral load has been shown to reduce progression of KS, including development of new lesions. People who've used either Cytovene (ganciclovir) or Famvir (famciclovir) to treat CMV (cytomegalovirus) also have fewer cases of KS, but these drugs are not recommended for prevention and treatment at this time.


Caused by the parasite cryptosporidium. Difficult to control. May lead to rapid weight loss and severe weakness. There is no standard treatment. Drugs being tested for treatment include paromomycin (Humatin), azithromycin (Zithromax), latrazuril and atovaquone (Mepron). Research with the promising drug nitazoxanide was stopped after the drug failed to win FDA approval. Also, bovine colostrum concentrate (Sporidin-G) is being tested for controlling diarrhea caused by crypto.

Transmission: Contaminated water. Oral/anal contact. Raw oysters. Failure to wash hands (after gardening, playing with pets, changing diapers, using the bathroom, etc.).

Symptoms: Severe persistent diarrhea. Also, nausea, vomiting, and stomach cramps.

Prevention: Bringing tap water to a rolling boil for three minutes kills the parasite. Water filters should be those that use distillation or reverse osmosis, those labeled as absolute (not "nominal") 1-µm filters, and those labeled as meeting NSF #53 for cyst removal. Not all bottled waters meet these standards; call the toll-free number on the bottle to check. Don't forget to use safe water for ice cubes and be careful with drinks made with tap water when you go out.

Cytomegalovirus (CMV)

Cytomegalovirus infection can be acquired throughout life by direct contact with bodily fluids. It is spread throughout childhood and later in adults through sexual activity. Approximately 40 to 100% of the U.S. adult population has been exposed to CMV. It primarily damages eyesight (CMV retinitis) and can lead to blindness. May affect other organs. CMV is a herpes virus, and thus lingers in your body forever.

Transmission: Sexually transmitted. Found in saliva, semen, respiratory excretions and urine. Presence is higher among positive men who have sex with men than in other groups. Also, CMV can remain dormant in the body (latent) and in immunocompromised people, CMV can be reactivated, producing disease in various organs, such as the eye.

Symptoms: Look out for floaters (spots in your vision), especially if increasing over time. Also watch for blurring when reading.

Prevention: A new drug has become FDA-approved. It is a version of ganciclovir (Cytovene) and is called valganciclovir (Valcyte). It should be considered for people with less than 50 T-cells who are CMV positive. Weigh the possibility of neutropenia (decreased white blood cells), anemia (especially if already taking Retrovir or hydroxyurea), conflicting reports of efficacy, lack of proven survival benefit, and risk of developing resistance to ganciclovir. Also, the drug is expensive and dose is an inconvenient 12 capsules a day (although the oral form of ganciclovir is a vast improvement over the old days of daily intravenous infusions). Do not use acyclovir (Zovirax) or valacyclovir (Valtrex). People whose T-cells have increased to more than 100 for three to six months with therapy, plus have a drop in their viral load, can stop taking CMV prophylaxis, but those with CMV disease should first check with their eye doctor.


Caused by the varicella-zoster virus (VZV, varicella means chickenpox and zoster means shingles). Varicella-zoster is a herpes virus, so it's with you forever. Shingles is a painful condition of blisters and sores that run along nerve paths, usually on one side of the body or as a band around your middle. It may occur early in HIV disease. Pain may persist after healing of skin lesions and may be difficult to control. People with HIV experience many more lesions. They are at greater risk of getting bacterial infections in their sores (try to keep them clean and dry as much as possible) and of a life-threatening spread to internal organs.

Transmission: Extremely contagious, through direct contact with skin lesions or through airborne droplets from the lesions getting into mucosal surfaces (nasal sinuses, lining of the mouth, etc.). VZV also seems to enter through the skin surfaces of sensory nerves and then travel down into the nerve fibers. Infectivity usually begins a couple of days before outbreak and continues until all sores are crusted over. For people with HIV, this can take several weeks.

Prevention: No recommendations as yet.

Mycobacterium Avium Complex (MAC)

Bacterial infection. Organisms of the M. avium complex are common in food, water, and soil. Almost everyone has the bacteria in their body.

Transmission: Not spread person to person.

Symptoms: Recurring fevers, fatigue, swollen glands, night sweats, diarrhea, and severe weight loss.

Prevention: Should be taken by people with less than 50 T-cells. Various medications are available. While it seems that people whose T-cells have increased to more than 100 for three to six months under therapy, with decreased viral loads, can stop prophylaxis without getting MAC, stopping prophylaxis is not yet recommended due to the insufficient number of people having been evaluated.


Cancers involving white blood cells. AIDS-related lymphoma is also called non-Hodgkin's lymphoma (NHL).

Transmission: None. Development of NHL is associated with Epstein-Barr virus, long-term HIV infection, and genetic factors.

Symptoms: Swollen lymph nodes, fever, night sweats, and weight loss.

Prevention: None.

Human Papilloma Virus (HPV)

A very common sexually transmitted virus that causes genital warts. Tends to be much more aggressive in people with HIV. Can lead to cancer of the cervix (the lower part of the uterus, leading into the vagina), especially the virus strains HVP-16 and HPV-18. May also cause infertility.

Prevention: As with herpes, condoms do not offer complete protection. To watch out for cancer, women should obtain two Pap smears during the first year after infection and if results are normal, a yearly Pap after that. HIV-positive men who have sex with men are at increased risk of anal cancer, but routine screening with an anal Pap smear is not yet recommended by the guidelines. Wouldn't hurt -- it's a little cotton swab that can pick up trouble. It's also been found to be cost-effective (medical jargon for "benefits are worth the price"). People with HIV, whether male or female, whether they have anal sex or not, are at greater risk for anal cancer.

For More Information

There's more useful information in the OI guidelines, published by the U.S. Public Health Service and the Infectious Diseases Society of America, including additional OIs, as well as information regarding pets, travel, children and pregnancy. Call 1-800-448-0440 for a free copy or visit

Always confer with your healthcare provider before initiating or discontinuing any medication.

Take Home Point

Continue to monitor your T-cells, even if you're not on therapy. You're more at risk for certain infections when your T-cells are at certain levels. If you can't, or don't want to take HIV meds, you can still take OI prevention medications (prophylaxis) to keep you healthier and out of the hospital.

What's HAART Got to Do with It?

Opportunistic infections have gone down as much as 85% in developed countries following the introduction of HAART (highly active antiretroviral therapy, the so-called "drug regimen"). According to the OI guidelines, "HAART is the most effective approach to preventing OIs and should be considered for all HIV-infected person who qualify for such therapy. . . . In addition, [prevention] against specific OIs continues to provide survival benefits even among person who are receiving HAART." [See "Adherence 101" and "To Start or not to Start?"]

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A note from The field of medicine is constantly evolving. As a result, parts of this article may be outdated. Please keep this in mind, and be sure to visit other parts of our site for more recent information!

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This article was provided by Positively Aware. It is a part of the publication Positively Aware. Visit Positively Aware's website to find out more about the publication.
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Strategies for Managing Opportunistic Infections
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