Opportunistic Infections (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 infection or by some medications, these germs can get out of… Read More


WHICH CANCERS AFFECT PEOPLE WITH HIV? Cancer is the uncontrolled growth of abnormal cells in the body. Cancer cells are called malignant cells. Malignant means bad and getting worse. Cancer has been associated with AIDS from the beginning of the epidemic. A group of unusual… Read More


WHAT IS CANDIDIASIS? Candidiasis, also known as Candida, is a common opportunistic infection (OI) in people with HIV. It is an infection caused by a common type of yeast (or fungus) called candida that is found in most people’s bodies. A healthy immune system keeps… Read More

Cryptococcal Meningitis

WHAT IS CRYPTOCOCCAL MENINGITIS? Cryptococcus is a fungus that is very common in the soil. It can get into your body when you breathe in dust or dried bird droppings. It does not seem to spread from person to person. Meningitis is the most common… Read More


WHAT IS CRYPTOSPORIDIOSIS? Cryptosporidiosis (crypto) is an infection caused by the parasite Cryptosporidium. A parasite gets its nutrients from another living organism (the host). Your body is the host when you have this infection. Crypto mainly affects the intestines and causes diarrhea. Crypto is easily… Read More

Cytomegalovirus (CMV)

WHAT IS CMV? Cytomegalovirus (CMV) is a common virus that can cause HIV-related opportunistic infections (OIs). Between 50-85% of the U.S. population tests positive for CMV by the time they are 40 years old. A healthy immune system keeps this virus in check. When immune… Read More


WHAT IS HEPATITIS? Hepatitis means inflammation, or swelling, of the liver. Viruses, alcohol, drugs (including prescription medications), or poisons can cause hepatitis. So can opportunistic infections (OIs) such as Mycobacterium Avium Complex (MAC) or Cytomegalovirus (CMV). Hepatitis is a very common disease. It can affect… Read More

Herpes Simplex Virus (HSV)

WHAT IS HERPES SIMPLEX VIRUS? Herpes simplex virus (HSV) refers to a group of viruses that infect humans. Like herpes zoster, HSV causes painful skin eruptions. Itching and tingling are usually the first signs, followed by a blister that breaks open. The infection stays dormant… Read More

Herpes Zoster (Shingles)

WHAT IS HERPES ZOSTER? Herpes zoster, also called shingles, is a very painful disease caused by the same herpes virus that causes chickenpox (varicella zoster virus). Like other herpes viruses, the varicella zoster virus has an initial infectious stage (chickenpox) followed by a dormant stage.… Read More

Human Papillomavirus (HPV)

WHAT IS HUMAN PAPILLOMAVIRUS? Human papillomavirus (HPV) is the most common sexually transmitted infection (STI). There are over 120 HPV types. One study found HPV in 77% of people assigned female at birth (AFAB) with HIV. HPV is transmitted easily during sexual activity. HPV is… Read More

Kaposi Sarcoma (KS)

WHAT IS KAPOSI SARCOMA? Kaposi sarcoma (KS) is a cancer. It originally was known as a disease affecting elderly people assigned male at birth (AMAB) of Eastern European or Mediterranean background. KS also occurs in African AMAB people and people with a weakened immune system.… Read More

Molluscum Contagiosum

WHAT IS MOLLUSCUM CONTAGIOSUM? Molluscum contagiosum, often called molluscum, is a skin infection caused by a virus. Molluscum causes small bumps (lesions) to appear on the skin. Most of them are less than half an inch in diameter. They have a hard white core. Some… Read More

Mycobacterium Avium Complex (MAC)

WHAT IS MYCOBACTERIUM AVIUM COMPLEX? Mycobacterium Avium Complex (MAC) is a serious illness caused by common bacteria. MAC is also known as MAI (Mycobacterium Avium Intracellulare). MAC infection can be localized (limited to one part of the body) or disseminated (spread through the whole body,… Read More

Non-Hodgkin Lymphoma (NHL)

WHAT IS NON-HODGKIN LYMPHOMA? AIDS-related lymphoma is sometimes called Non-Hodgkin Lymphoma (NHL). In 1985, the Centers for Disease Control and Prevention (CDC) added NHL to the list of diseases that define AIDS. Hodgkin Disease, another type of lymphoma, is rare in people with HIV. Lymphoma… Read More

Pneumocystis Pneumonia (PCP)

WHAT IS PNEUMOCYSTIS PNEUMONIA? Pneumocystis pneumonia (PCP or pneumocystis) is the most common opportunistic infection (OI) 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.  Although PCP is… Read More

Progressive Multifocal Leukoencephalopathy (PML)

WHAT IS PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY? Progressive multifocal leukoencephalopathy (PML) is a serious viral infection of the brain. Progressive means that this disease gets worse over time. Multifocal means that it shows up in several places at the same time. Leukoencephalopathy means a disease of the… Read More


WHAT IS TOXOPLASMOSIS? Toxoplasmosis (toxo) is an infection caused by the single-celled parasite toxoplasma gondii. A parasite lives inside another living organism (the host) and takes all of its nutrients from the host. The most common illness caused by toxo is an infection of the… Read More

Tuberculosis (TB)

WHAT IS TUBERCULOSIS? Tuberculosis (TB) is an infection caused by bacteria. TB usually affects the lungs but sometimes can affect other organs, especially in people with HIV who have a CD4 cell count under 200 cells/mm3. TB is a serious disease worldwide. Almost one-third of… Read More