Valley fever's deadly history

The earliest recorded case of coccidioidomycosis was documented in Argentina in 1892, when a soldier was diagnosed with what was first thought to be an infection of coccidia — parasitic protozoans, like cryptosporidium and toxoplasma, that infect the intestines of animals, including chickens, cows, dogs and cats. The soldier lived with the disease for 11 years, during which time his doctors realized it was not caused by a protozoa but by a fungus. The name, however, stuck.

In the 1930s, researchers identified the culprit as a soil fungus during a severe outbreak of coccidioidomycosis in the San Joaquin Valley of California, which also gave the disease its nickname of Valley Fever. During World War II, thousands of soldiers training in the Southwest contracted the disease, as did 22 Navy Seals training in Coalinga, Calif., in 2002.

Wildlife has also proven susceptible to the disease. In California, after the Jan. 17, 1994, Northridge earthquake triggered massive landslides in the Santa Rosa Mountains, the prevailing winds carried dust out to the Pacific coast where a population of sea lions, which had no previous exposure to the soil fungus and thus no immunity, was decimated by the disease.

People didn’t fare so well either after the quake. In Ventura County, Calif., which had seen only 52 cases of the disease during the entire previous year, more than 200 people contracted acute coccidioidomycosis between late January and mid-March and three people died.

Sara E. Pratt

Sara E. Pratt

Pratt, EARTH's senior editor, is based in Boulder, Colo. She is a graduate of the earth and environmental science journalism dual master’s program at Columbia University and Lamont-Doherty Earth Observatory and has written for Discover, Oceanus, Geotimes, NOVA and NOVA ScienceNow, and worked in scientific publishing and educational outreach. Email: Twitter: @GeoScienceSara.

Sunday, September 7, 2014 - 02:00