Tennessee Fungal Outbreak Linked to Soil Exposure Leaves 35 Ill, 1 Dead; What is histoplasmosis?

Health officials in Tennessee are investigating an outbreak of infections tied to a fungus found in soil, after at least 35 people became sick. At least one person has also died of histoplasmosis, which affects the lungs and feels like the flu. Doctors say that while most people recover, in rare cases, death can also happen in those with weak immunity levels. The fungus that causes histoplasmosis lives in soil, especially in areas along the Ohio and Mississippi River valleys, including central Tennessee. It can become airborne when soil is disturbed, often through construction, landscaping, farming, or yardwork, or through contact with bird or bat droppings in soil, according to the US Centers for Disease Control and Prevention (CDC). Tennessee Department

of Health officials said the outbreak in Tennessee is centered in Maury and Williamson counties, south of Nashville, as the cases started rising and being reported since September, mostly in the towns of Spring Hill and Thompson’s Station. It “is commonly found throughout the soil in Tennessee, so it can be challenging to completely prevent exposure,” the department said in a statement. The CDC is providing technical support for the investigation. Many of those infected had also gotten tests conducted for flu and COVID-19, both of which came back negative. Later, upon hospitalisation, when the situation deteriorated, doctors conducted tests for histoplasmosis.

Most cases of the fungus are mild

According to experts, more than 90 per cent of those exposed to the fungus never get sick, and the disease does not spread between people or animals. The New York Times quoted Dr Lili Tao, a professor at Vanderbilt University Medical Center, who said most cases are mild and treatable. “Outbreaks of histoplasmosis have been documented as far back as the late 1930s, with case numbers ranging from a few to several hundred,” she told The Times. Doctors in the area have been asked to report any patients with symptoms who test positive or may be linked to known cases.

How does histoplasmosis spread?

Histoplasmosis is a type of fungal infection that spreads in your lungs, and you get it from breathing in the fungus Histoplasma capsulatum (H. capsulatum). The fungus lives in the soil in many parts of the world, including the US. It is most commonly found where there are bird or bat droppings in the soil. The fungus H. capsulatum gets into your lungs when you breathe it in from the soil. There, it enters your white blood cells and changes from a mold into its infectious form as a yeast. In most people, your immune cells destroy it or wall it off from your body with granulomas, before you ever notice any symptoms. In certain circumstances, it can make you sick.

Signs and symptoms of histoplasmosis

A few signs and symptoms of histoplasmosis can include:

• Fever
• Cough
• Sweating
• Breathlessness
• Chest pain
• Headache
• Muscle aches
• Rash or bumps on your lower legs

Chronic cavitary pulmonary histoplasmosis can additionally cause night sweats and weight loss. In up to 90 per cent of people, breathing in H. capsulatum doesn’t cause any symptoms, or their symptoms resolve on their own.Also read: What a US Exit From the WHO Means for Global Health and Future Pandemic Risks

What are the risk factors for histoplasmosis?

You are more at risk for histoplasmosis if you have a job or hobbies that can disturb large concentrations of the fungus. It includes farming, keeping chickens or birds, or construction work.

What are the complications of histoplasmosis?

Serious complications of histoplasmosis include scarring or lung damage, acute respiratory distress syndrome, central nervous system swelling, headaches, and infection spreading to other parts of the body, including bone marrow.