Widespread histoplasmosis lung infections across the US: a study
The fungus that causes the disease known as histonplasma is found in the soil of almost every US state, a new study shows. The researchers behind the work say doctors may be relying on outdated risk maps and therefore miss diagnoses of infections, which can sometimes be fatal.
According to CDC, histoplasma, or histo, is found in the soil of central and eastern US states, primarily in Ohio and the Mississippi River valleys. But that assumption is based on research from the 1950s and 1960s, says the team behind the new paper published in Clinical Infectious Diseases. When a person inhales fungal spores, they can get an infection called histoplasmosis.
“Every few weeks I get a call from a doctor in the Boston area — a different doctor each time — about a case I can’t solve,” said study author Andrej Spec, an associate professor of medicine at Washington University in St. Louis. , in press release. “They always start by saying, ‘We don’t have a histo here, but it really looks like a histo.’ I say, ‘You keep calling me about this. You have a history.'”
Lead author Patrick B. Mazi, clinical associate professor of infectious diseases also at Washington University in St. Louis, and colleagues analyzed more than 45 million Medicare fee-for-service beneficiaries from 2007 to 2016. They looked at nationwide diagnoses of three fungal diseases: histoplasmosis, coccidioidomycosis, and blastomycosis. Histo, the most common, caused clinically relevant disease rates in at least one county in 48 of the 50 states, as well as in Washington, DC. The other two infections were found in more than half of the states.
“Yeast infections are much more common than people realize and spread,” Spec said in a statement. “The scientific community has invested too little in the study and development of treatments for yeast infections. I think that is starting to change, but slowly.” Climate change can be driving this is spreading as warming temperatures make more habitat suitable for the fungus.
Although histopathology can be easily resolved in healthy adults, and many people who are exposed never develop symptoms, those who are immunocompromised, as well as infants and people over 55 years of age can develop more serious illness, including cough, fever, chest pain, body aches and fatigue, according to at the CDC. Symptoms appear within three to 17 days after exposure; most symptoms will disappear within a month, but if it spreads from the person’s lungs, the disease can become serious and require months of treatment.
Humans can be exposed to histo and other fungal pathogens through activities that damage the soil, such as agriculture, landscaping, and construction. They can also be exposed inside caves and while working in basements and attics. Spec noted, “It is important for the medical community to understand that these fungi are everywhere today and that we must take them seriously and include them in the consideration of diagnoses.”