Division of Foodborne, Bacterial and Mycotic Diseases (DFBMD)
Clinical Features
Symptomatic infection usually presents as a flu-like illness with fever, cough, headaches, and myalgias. Some patients fail to recover and develop chronic pulmonary infection or widespread disseminated infection (affecting mucosal surfaces, liver, spleen, adrenal gland and meninges). Acute septic presentation seen in some HIV-infected persons.
Etiologic Agent
Histoplasma capsulatum var. capsulatum. In Africa: H.capsulatum var. duboisii.
Resovoir
Soil contaminated with bird or bat droppings. Endemic in parts of the central and eastern United States along Ohio and Mississippi river valleys. Microfoci in Central and South America, Africa, India, and Southeast Asia.
Incidence
Approx. 80% of population living in areas with endemic disease is skin-test positive. Of HIV-infected persons in these areas, 10% - 25% develop disseminated histoplasmosis.
Sequelae
Permanent lung damage with chronic disease. Mortality rate is about 10% in HIV-infected persons with disseminated disease.
Transmission
Inhalation of airborne conidia (spores) after disturbance of contaminated soil.
Risk Groups
Persons in areas with endemic disease with exposures to accumulations of bird or bat droppings (e.g., construction or agricultural workers, spelunkers). High risk groups are immunocompromised persons (e.g., persons with cancer, transplant recipients, persons with HIV infection).
Surveillance
Reportable in some states in areas with endemic disease. No national surveillance exists.
Challenges
Identifying modifiable risk factors for disease in immunocompromised and debilitated persons. Developing sensitive and specific methods for earlier diagnosis. Determining which risk groups may benefit from chemoprophylaxis.
Opportunities
Defining risk factors for disease in immunocompromised persons. Developing more sensitive and specific tests for diagnosis.
1600 Clifton Road NE
MS-C09
Atlanta, GA 30333
Phone: +1-800-311-1603