Stick a shovel in the soil and you’ll see a lot of things beneath the surface: threadlike roots, slithering worms, and more. What you can’t see are all the microorganisms, including a fungus called histoplasma.
This fungus causes a lung infection called histoplasmosis, which is mild for most people with healthy immune systems. But for people with HIV or AIDS whose immune systems are already compromised, histoplasmosis is a serious health concern.
Who Is Most at Risk for Histoplasmosis?
Anyone can get histoplasmosis if they’ve spent time in “hot spots” where the fungus is common. In the U.S., it’s most common in the Eastern and Midwestern regions. But it can also show up in the South. And you don’t need to get dirty to get sick: Histoplasma strikes from the air.
The fungus thrives best in dirt that contains bird and bat droppings. When this contaminated soil or dust is moved around – say, during construction, cave exploration, or gardening – the fungus releases spores into the air. If you breathe those in, you can get histoplasmosis.
Histoplasmosis, or at least exposure to the histoplasma fungus, is extremely common, especially around the Ohio and Mississippi River valleys. As many as 250,000 people in the U.S. are diagnosed with it every year.
Why Is HIV-Associated Histoplasmosis So Dangerous?
If you have HIV and get infected, your body may not fight it very well. That’s because HIV weakens your immune system. This type of illness is called an opportunistic infection.
Histoplasmosis is a common opportunistic infection in people with HIV or AIDS. But if you’re on antiretroviral therapy (ART), that lowers your risk. It helps protect you, so you don’t have to live in fear of this fungus.
Of course, not everyone with HIV is on ART in the U.S. or other countries. For example, ART is not widely available in Latin America. There, histoplasmosis kills around 30% of HIV and AIDS patients who are diagnosed with the fungal infection.
What Are the Symptoms of Histoplasmosis?
Histoplasmosis doesn’t always cause symptoms in healthy people. But if you have HIV and get histoplasmosis, you likely will have them. Symptoms usually set in between 3 and 17 days after you breathe in the fungal spores. It’s a lung infection, so you may have a cough or chest pain. Other symptoms are flu-like, such as:
Most people recover within a month, but when you have HIV or AIDS, that may not be the case. You’re at risk for severe disease. In some severe cases, the infection spreads through the bloodstream and can affect other parts of the body, such as your:
- Spinal cord
- Lymph nodes
- Adrenal glands
- Digestive system
- Bone marrow
This severe form is called progressive disseminated histoplasmosis, and it mainly occurs in immune-compromised people.
How to Prevent HIV-Associated Histoplasmosis
In regions where the histoplasma fungus thrives, histoplasmosis has been called an “AIDS-defining illness.” These are some science-backed ways you can protect yourself from infection.
Take your HIV medicine exactly as prescribed. It helps strengthen your immune system, so you’re more likely to prevent or fight off opportunistic infections like histoplasmosis.
Lessen your exposure to histoplasmosis whenever possible. It’s harder to do this if you live in an area where the fungus thrives. But you can try to avoid activities that raise your risk. For example, you may want to pass on gardening. Steer clear of bird and bat droppings, too. You’ll want to avoid cleaning or handling birdhouses and chicken coops.
Reconsider renovation/construction projects. If you’re renovating a home, budget and materials are probably top of mind. But if you have HIV, you should consider histoplasmosis, too. Construction and renovation sites are known to be sources of these infections.
Ask your doctor about preventive medicine. One study found that an antifungal drug, itraconazole, reduced histoplasmosis cases in people with HIV who live or work in places where histoplasmosis is very common. But it did not help with survival rates.
Your doctor may have other suggestions, such as places or activities to avoid when you plan a vacation. Be sure to keep your doctor and other members of your health care team in the loop.