Epidemiology of Coccidioidomycosis Outbreaks Reported Worldwide, 1940–2015

February 15, 2018

Coccidioidomycosis, also known as Valley fever, is a disease caused by the fungus Coccidioides. The disease is endemic to the western United States, northern Mexico, and parts of Central and South America. Infection occurs primarily by inhalation of spores, which are known to persist in soil, and nearly 40 percent of infected people become ill, typically within one to three weeks of exposure and often with a flu-like syndrome characterized by cough, shortness of breath, fever, and fatigue. Each year in the United States, about 10,000 coccidioidomycosis cases are reported. However, the disease is widely underdiagnosed, and those cases probably represent a small fraction of the actual number.

Because much remains unknown about its epidemiology and because coccidioidomycosis outbreaks have not been systematically studied, Freedman, et al. (2018) reviewed documented coccidioidomycosis outbreaks from the period 1945–2015 to identify common features and prevention opportunities. They found that most outbreaks (85 percent) were associated with environmental exposures; the two largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where coccidioidomycosis was not previously known to be endemic, and more than half involved occupational exposures. Because coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent, the authors of this study argue that increased awareness of coccidioidomycosis among public health professionals, healthcare providers, and the public is needed.

Reference: Freedman M, et al. Epidemiology of Coccidioidomycosis Outbreaks Reported Worldwide, 1940–2015. Emerging Infectious Diseases. Vol. 24, No. 3. 2018.

Source: CDC