Histoplasmosis, 2019

In 2019, there were 61 confirmed and 153 probable cases of histoplasmosis, an increase from 2017 and 2018. A new national case definition was implemented 2017; thus, comparisons to earlier years are difficult to make. The median age of cases was 52 years (range, 3 to 86 years); 133 (62%) were male. Of the 174 cases with race reported, 162 (93%) were white, 5 (3%) were black, 5 (3%) were Asian/ Pacific Islander, 1 (1%) was American Indian/Alaskan Native, and 1 (1%) reported more than one race. Of the 150 with ethnicity reported, 5 (3%) were Hispanic. One hundred one cases (49%) were hospitalized, for a median of 4 days (range, 1-28 days), and of the 166 whose status was known, 61 (37%) were immunocompromised. Ten (5%) cases died, and histoplasmosis was the primary cause of death in 8 of these cases.

From 2017 to 2019, 581 cases of histoplasmosis have been reported. The average annual incidence of histoplasmosis in Minnesota was 3.3 cases per 100,000 population.

Histoplasmosis is caused by the soil dwelling dimorphic fungus Histoplasma capsulatum. Infection typically results from inhalation of aerosolized spores, and symptomatic infections usually involve pulmonary disease, though disseminated or non-pulmonary infections are possible. The Mississippi River Valley is known to be an endemic area. Additionally, geographic microfoci exist inside and outside endemic areas, and are usually associated with soil containing bird or bat guano. Common activities associated with exposure include farming, exposure to soil enriched with bird or bat guano, remodeling or demolition of old buildings, and clearing trees or brush in which birds have roosted. A subset of cases from 2018 and 2019 were enrolled in an enhanced surveillance interview, including 50 confirmed cases and 47 probable cases. These cases were asked about possible exposures, including bird or bat droppings, construction, demolition, gardening or other handling of plants or trees. Eighty-two (85%) cases reported at least one of these. The most commonly reported exposure was gardening or other handling of plants or trees (51 cases, 53%), while 32 (33%) cases reported exposure to construction or demolition, and 24 (25%) cases reported exposure to either bird or bat guano.

• Find up to date information at>> Histoplasmosis (Histoplasma capsulatum)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2019