HIV 11 – HIV and Opportunistic infections

Doctors were first alerted to the existence of AIDS when patients clinically presented with opportunistic infections.1

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What is an opportunistic infection?

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An opportunistic infection is an infection that is more frequent or more severe because of a weakened immune system, called HIV immunosuppression.2
When a person with HIV gets an opportunistic infection, they will get diagnosed with AIDS (also known as HIV stage 3), the most serious stage of HIV infection.2
HIV treatments have become better at keeping the immune system strong and the level of HIV low. As a result, opportunistic infections have become less common, compared with when HIV first become a public health issue, where the rate of opportunistic infections were high.1,2
It wasn’t until the mid-1990s with the introduction of highly effective combination antiretrovirals that opportunistic infection-related illness and death in persons with HIV was reduced. To this day, if a person infected with HIV is not virally suppressed, then opportunistic infections will continue to cause preventable illness and death.1
Learn here more about opportunistic infections and preventative measures to keep them under control.

Why would a person get an opportunistic infection?

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If a patient takes their HIV treatment properly, the levels of HIV virus in their body are kept low. This allows their immune fighting cells to recover and fight off these opportunistic infections.2
It is important to know about the most common infections that occur in people living with HIV so that they can be detected early and treated.2

Types of opportunistic infections

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Name of infection: Oropharyngeal and oesophageal candidiasis

Type: Fungal infection

This illness is caused by an infection with a common type of fungus called Candida.2 Candidiasis is most often observed in patients with a CD4 cell count of less than 200 cells/mm3.1 However, candidiasis is only considered an opportunistic infection when it infects the oesophagus (swallowing tube) or lower parts of the lung.2 Signs include painless, creamy white, plague-like lesions that occur on or in the mouth area.1


Name of infection: Cryptococcosis (also called cryptococcal disease/ meningitis)

Type: Fungal infection2

Cryptococcal meningitis is a common opportunistic infection, and a leading cause of death in people living with HIV.3

Most cases are observed in patients who have CD4 cell counts < 100 cells/μL.1 In HIV-infected patients, cryptococcosis commonly presents as a type of meningitis with fever, malaise, and headache,1u though it can also infect any part of the body, for example the lungs, and cause pneumonia.2


Name of infection: Cytomegalovirus (CMV)

Type: Viral infection2

Can infect multiple parts of the body and cause pneumonia, gastroenteritis, infection of the brain, and sight-threatening retinitis (infection of the back of the eye).2 Retinitis may present with floaters or vision deficits. If CMV infects the colon or oesophagus it can cause symptoms of weight loss, loss of appetite, stomach pain, nausea and fever.1


Name of infection: Diarrhoeal disease

Type: Bacteria/Parasite

Different types of organisms can cause diarrhoea.2 Usually picked up from contaminated food or water.2i People with HIV and low CD4 cell counts have more severe diarrhoea and associated illness as they have little immunity to fight off the germs.1


Name of infection: Herpes simplex virus (HSV)

Type: Viral infection

A common virus, that for most people, does not cause major problems but in HIV-infected patients, can cause more serious infections. HSV can cause painful cold sores (fever blisters) in and around the mouth or painful ulcers in the genital area.2


Name of infection: Human papillomavirus (HPV)

Type: Viral infection

Certain types of HPV can increase the risk of cervical cancer (cancer of the lower part of the uterus in a woman).1,2 HIV infection and low CD4 cell count are strongly associated with HPV infection and with the development of cancerous cervical cells.1


Name of infection: Kaposi’s sarcoma

Type: Viral infection

This cancer, also known as KS, is caused by a virus that causes the small blood vessels (capillaries) to grow abnormally. Because capillaries are located throughout the body, KS can occur anywhere, seen as pink or purple spots on the skin that can be raised or flat. KS can become life-threatening when it affects organs inside the body, such as the lung, lymph nodes, or intestines.1,2


Name of infection: Tuberculosis (TB)

Type: Bacterial infection

This infection is caused by the bacteria Mycobacterium tuberculosis. Inhaling the bacteria can lead to an infection in the lungs.2 Classis symptoms include cough, fever, night sweats and weight loss.1,2 Although the disease usually occurs in the lungs, it may also affect and present in other parts of the body, especially if left untreated.2,3


Name of infection: Mycobacterial diseases or infections

Type:  Mycobacteria

Mycobacteria live in our environment, including in the soil and dust particles. In people with severely damaged immune systems, infections with these bacteria spread throughout the body and can be life-threatening.2


Name of infection: Pneumonia

Type: Bacteria, virus or fungus2

Pneumonia is a severe infection of one or both of the lungs. Symptoms include a cough (with mucus), fever, chills and trouble breathing. Pneumonia occurs in people with weakened immune systems and can be life-threatening. Vaccines are effective against some types of pneumonia.2


Name of infection: Toxoplasmosis

Type: Parasite

Carried by animals, this parasite is spread through inhaling dust or eating food contaminated with animal excretions. Cats are often the cause.2


Name of infection: Varicella zoster and herpes zoster

Type : Viral infection

Varicella zoster is commonly known as chickenpox and Herpes zoster is commonly known as shingles. Shingles is more common in the elderly or immunocompromised such as in HIV. Severe complications of shingles can include blindness and other nerve-related damage.1

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