Prolonged coccidioidomycosis transmission seasons in a warming California: a Markov state transition model of shifting disease dynamics.
Simon K Camponuri, Jennifer R Head, Philip A Collender, Amanda K Weaver, Alexandra K Heaney, Kate A Colvin, Abinash Bhattachan, Gail Sondermeyer-Cooksey, Duc J Vugia, Seema Jain, Justin V Remais
Author Information
Simon K Camponuri: Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
Jennifer R Head: Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
Philip A Collender: Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
Amanda K Weaver: Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
Alexandra K Heaney: Herbert Wertheim School of Public Health and Human Longevity, University of California San Diego, San Diego, CA, USA.
Kate A Colvin: Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
Abinash Bhattachan: Department of Geosciences, Texas Tech University, Lubbock, TX, USA.
Gail Sondermeyer-Cooksey: Infectious Diseases Branch, California Department of Public Health, Richmond, CA, USA.
Duc J Vugia: Infectious Diseases Branch, California Department of Public Health, Richmond, CA, USA.
Seema Jain: Infectious Diseases Branch, California Department of Public Health, Richmond, CA, USA.
Justin V Remais: Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA. ORCID
Coccidioidomycosis, an emerging fungal disease in the southwestern United States, exhibits pronounced seasonal transmission, yet the influence of current and future climate on the timing and duration of transmission seasons remains poorly understood. We developed a distributed-lag Markov state transition model to estimate the effects of temperature and precipitation on the timing of transmission season onset and end, analysing reported coccidioidomycosis cases ( = 72 125) in California from 2000 to 2023. Using G-computation substitution estimators, we examined how hypothetical changes in seasonal meteorology impact transmission season timing. Transitions from cooler, wetter conditions to hotter, drier conditions were found to significantly accelerate season onset. Dry conditions (10th percentile of precipitation) in the spring shifted season onset an average of 2.8 weeks (95% CI: 0.43-3.58) earlier compared with wet conditions (90th percentile of precipitation). Conversely, transitions back to cooler, wetter conditions hastened season end, with dry autumn conditions extending the season by an average of 0.69 weeks (95% CI: 0.37-1.41) compared with wet conditions. When dry conditions occurred in the spring and autumn, the transmission season extended by 3.70 weeks (95% CI: 1.23-4.22). With prolonged dry seasons expected in California with climate change, our findings suggest this shift will extend the period of elevated coccidioidomycosis risk.
