| Climate Factors Influencing Coccidioidomycosis Seasonality and Outbreaks Andrew C. Comrie Department of Geography and Regional Development, University of Arizona, Tucson, Arizona, USA Abstract
Although broad links between climatic factors and coccidioidomycosis have been established, the identification of simple and robust relationships linking climatic controls to seasonal timing and outbreaks of the disease has remained elusive. Using an adaptive data-oriented method for estimating date of exposure, in this article I analyze hypotheses linking climate and dust to fungal growth and dispersion, and evaluate their respective roles for Pima County, Arizona. Results confirm a strong bimodal disease seasonality that was suspected but not previously seen in reported data. Dispersion-related conditions are important predictors of coccidioidomycosis incidence during fall, winter, and the arid foresummer. However, precipitation during the normally arid foresummer 1.5-2 years before the season of exposure is the dominant predictor of the disease in all seasons, accounting for half of the overall variance. Cross-validated models combining antecedent and concurrent conditions explain 80% of the variance in coccidioidomycosis incidence. Key words: climate, Coccidioides, coccidioidomycosis, environment, meteorologic factors, rain, seasonal variation, southwestern United States, weather. Environ Health Perspect 113:688-692 (2005) . doi:10.1289/ehp.7786 available via http://dx.doi.org/ [Online 3 March 2005]
Address correspondence to A.C. Comrie, Department of Geography and Regional Development, University of Arizona, 409 Harvill Building, Box #2, Tucson, AZ 85721-0076 USA. Telephone: (520) 621-1585. Fax: (520) 621-2889. E-mail: comrie@arizona.edu The assistance of J. Tabor for data acquisition, B. Bonanno for preliminary analyses, and K. Kolivras and J. Galgiani for comments is gratefully acknowledged. Partial funding of the preliminary analyses was provided by the Arizona Disease Control Research Commission. The author declares he has no competing financial interests. Received 23 November 2004 ; accepted 3 March 2005. The full version of this article is available for free in HTML or PDF formats. |
