Coccidioidomycosis Outbreaks, United States and Worldwide, 1940-2015

Abstract

Coccidioidomycosis causes substantial illness and death in the United States each year. Although most cases are sporadic, outbreaks provide insight into the clinical and environmental features of coccidioidomycosis, high-risk activities, and the geographic range of Coccidioides fungi. We identified reports published in English of 47 coccidioidomycosis outbreaks worldwide that resulted in 1,464 cases during 1940-2015. Most (85%) outbreaks were associated with environmental exposures; the 2 largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where the fungus was not previously known to be endemic, and more than half of outbreaks involved occupational exposures. Coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent given the unknown effectiveness of environmental control methods and personal protective equipment; therefore, increased awareness of coccidioidomycosis outbreaks is needed among public health professionals, healthcare providers, and the public.

Keywords: Coccidioidomycosis; United States; Valley fever; coccidioides; disease outbreaks; epidemiology; fungi; worldwide.

Figure 1

Coccidioidomycosis cases, United States and worldwide, 1940–2015. A) Outbreak-related cases, by onset year (in 5-year periods) and environmental association (N = 1,464 cases). B) Environment-associated outbreaks, by onset year and outbreak location (N = 40 outbreaks).

Figure 2

Locations of environment-associated coccidioidomycosis outbreaks, by state or territory and whether the outbreak revealed new or confirmed suspected endemicity (n = 40), United States, Mexico, and Brazil, 1940–2015.