Activities and Jobs Associated with Histoplasmosis

Anyone who works with or near material contaminated with Histoplasma can develop histoplasmosis. Most people exposed to Histoplasma never have symptoms. For people who do get sick, the severity of histoplasmosis varies widely. The severity depends on the amount and length of the exposure and whether the person has other conditions that might put them at higher risk for developing the severe forms of histoplasmosis. Symptoms of histoplasmosis usually appear between 3 and 17 days after a person breathes in the fungal spores.

Activities associated with histoplasmosis

Environmental disruption of Histoplasma habitats is often a key factor associated with histoplasmosis outbreaks1 and with isolated cases,2 although to a lesser extent. These activities include:

  • Disturbance of large accumulations of bird or bat droppings (scraping droppings from a bridge; shoveling droppings from a building or other structure; cleaning a chicken coop)
  • Soil disruption (digging or excavation)
  • Plant matter disruption (handling trees or landscaping)
  • Demolition, construction, or renovation
  • Working in caves
Jobs associated with histoplasmosis

In areas where Histoplasma is common, people who work in construction, demolition, and extraction occupations and in agriculture and forestry industries may be at higher risk for histoplasmosis.2 People who work in other occupations or industries and are exposed to bird or bat droppings or are involved with activities that disrupt the environment are also at risk.

Most of what we know about specific jobs that may be related to a higher chance of getting sick with histoplasmosis comes from outbreak investigations. Approximately one-third of histoplasmosis outbreaks in the United States are work-related.1 However, outbreak-related histoplasmosis cases represent only a small fraction of overall known cases (about 5%).2 Examples of people affected by work-related histoplasmosis outbreaks include:1

  • Bridge workers
  • Construction or demolition workers
  • Farmers
  • Landscapers or tree removal workers
  • Microbiology laboratory workers

Histoplasmosis outbreaks have also affected people who were exposed in the workplace but not directly involved in activities that initiated the outbreak (for example, outbreaks affecting office building workers after construction or renovation).1

  1. Benedict K, Mody RK [2016]. Epidemiology of histoplasmosis outbreaks, United States, 1938-2013. Emerg Infect Dis 22(3):370–378.
  2. Benedict K, McCracken S, Signs K, Ireland M, Amburgey V, Serrano JA, Christophe N, Gibbons-Burgener S, Hallyburton S, Warren KA, Keyser Metobo A, Odom R, Groenewold MR, Jackson BR [2020]. Enhanced surveillance for histoplasmosis—nine states, 2018–2019. Open Forum Infect Dis ;7(9):ofaa343.