Coccidioidomycosis: A Contemporary Review

Abstract

Coccidioidomycosis, colloquially known as Valley Fever, is an invasive dimorphic fungal infection caused by Coccidioides immitis and C. posadasii. The fungi are found in the arid desert soils of the southwestern US, as well as in parts of Mexico and Central and South America. Acquisition is typically via inhalation of arthroconidia which become airborne after both natural (e.g., earthquakes, dust storms, and fires) and human-related events (e.g., military maneuvers, recreational activities, agriculture, and construction). The incidence of infection in increasing likely a result of both climatic and populational changes. Further, the recognized geographic distribution of Coccidioides spp. is expanding, as cases are being diagnosed in new areas (e.g., eastern Washington, Oregon, and Utah). Most coccidioidal infections are asymptomatic (60%); however, approximately one-third develop a pulmonary illness which is a leading cause of community-acquired pneumonia in highly endemic areas. Uncommonly (0.5–2% of cases), the infection disseminates to extrapulmonary locations (e.g., skin, bones/joints, and the central nervous system), and is most commonly seen among persons with cellular immunodeficiencies (e.g., transplant recipients, HIV, and pregnancy) and non-Caucasian races (especially African Americans and Filipinos). The diagnosis of coccidioidomycosis requires astute clinical suspicion and laboratory findings, including positive serology, cultures, and/or histopathology results. Treatment is warranted among persons with pneumonia who have risk factors for complicated disease and among those with extrapulmonary disease. Novel antifungals with improved fungicidal activity and rapidity of action with fewer side effects and drug interactions are needed. Preventive strategies (e.g., education regarding the disease, dust avoidance, mask wearing, including among select groups, antifungal prophylaxis, and surveillance laboratory testing) are advised for residents and travelers to endemic areas. Currently, no preventive vaccine is available. Coccidioidomycosis has been recognized for over a century, and an expanding wealth of knowledge has been gained regarding this emerging infectious disease which will be reviewed here.

Dust Storms, Valley Fever, and Public Awareness

“…Comrie (2021) also cautioned that a time lag between dust storms and coccidioidomycosis cases was not considered in Tong et al (2017), which examined yearly, not monthly, correlations. Due to the 1-3 weeks incubation period of coccidioidomycosis (Crum, 2022) and further lag between symptom onset and submission of a case report, the time lag between exposure and case reporting is estimated to be 1-1.5 months (Comrie, 2005;Tsang et al, 2010), which should not significantly affect variations on an annual scale. Nevertheless, the data reporting issue, considering its potential effect on interpreting scientific findings, needs to be explicitly included in the coccidioidomycosis case data set.…”

Immunologic Diagnosis of Endemic Mycoses

“…The two cryptic and dimorphic fungi Coccidioides immitis and Coccidioides posadasii cause coccidioidomycosis. The former species occurs in the Central Valley of California (San Joaquin Valley), but has now been detected as far north as east of Washington [ 34 ]. The latter species is regularly found in Arizona, Texas, Utah, Mexico, and Central and South America [ 35 ].…”

“…The latter species is regularly found in Arizona, Texas, Utah, Mexico, and Central and South America [ 35 ]. The at-risk individuals to be infected with these fungi include archeologists, laboratory staff handling the coccidioidomycosis agents, and visitors to endemic areas [ 34 ]. Coccidioidomycosis is often asymptomatic or occurs as a respiratory syndrome with undistinguishable, self-limiting symptoms.…”

Aspectos da COVID-19 como fatores de risco para a infecção ou reativação da coccidioidomicose: uma revisão sistemática

“…A primeira descrição do patógeno foi realizada em 1892 na Argentina, em um soldado que apresentava lesões ulcerativas na pele da face. A biópsia revelou organismos com aparência de protozoário, sendo descrito como um coccídio pelo pesquisador médico Alejandro Posadas (Crum, 2022;Kollath et al, 2019;Kirkland et al, 2022). No fim da década de 1890, um caso clínico similar foi descrito na Califórnia, Estados Unidos da América, em que um indivíduo com lesões cutâneas evoluiu para o óbito e a necrópsia revelou o comprometimento dos pulmões, linfonodos, peritônio, fígado e outros órgãos por estruturas leveduriformes.…”

“…Essas estruturas examinadas ao microscópio foram consideradas como semelhantes a coccídios, e os pesquisadores Gilcrest e Rixford nomearam o organismo Coccidioides immitis. Posteriormente, esses mesmos pesquisadores descobriram que o organismo não era um protozoário, mas um fungo dimórfico (Crum, 2022).…”