Coccidioidomycosis: An underreported cause of death-Arizona, 2008-2013

Access to Urgent Care Practices Improves Understanding and Management of Endemic Coccidioidomycosis: Maricopa County, Arizona, 2018-2023

BACKGROUND

Coccidioidomycosis within endemic regions is often undiagnosed because appropriate testing is not performed. A dashboard was developed to provide information about the prevalence of coccidioidomycosis throughout the year.

METHODS

Banner Urgent Care Service has many clinics within Maricopa County, Arizona, a highly endemic region for coccidioidomycosis. All clinic visits and subset analyses for patients with International Classification of Diseases, Tenth Revision codes for pneumonia (J18.*) or erythema nodosum (L52) during 2018-2024 were included. Tabulated were daily frequencies of visits, pneumonia and erythema nodosum coding, coccidioidal testing, and test results. Banner Urgent Care Services' counts of monthly coccidioidomycosis diagnoses were compared with those of confirmed coccidioidomycosis cases reported to Maricopa County Department of Public Health.

RESULTS

Monthly frequencies of urgent care coccidioidomycosis diagnoses strongly correlated with public health coccidioidomycosis case counts (r = 0.86). Testing frequency for coccidioidomycosis correlated with overall pneumonia frequency (r = 0.52). The proportion of pneumonia due to coccidioidomycosis varied between <5% and >45% within and between years. Coccidioidomycosis was a common cause of erythema nodosum (65%; 95% confidence interval, 45%-67%) and independent of pneumonia. Over half of Banner Urgent Care Services' coccidioidomycosis diagnoses were coded for neither pneumonia nor erythema nodosum.

CONCLUSION

Data provided by the coccidioidomycosis dashboard can assist urgent care practitioners in knowing when coccidioidomycosis is prevalent in the community. Patients with exposure to endemic coccidioidomycosis who develop erythema nodosum or pneumonia should routinely be tested for coccidioidomycosis. Data from private health care organizations can augment surveillance of diseases important to public health.

Coccidioidomycosis in Northern Arizona: an Investigation of the Host, Pathogen, and Environment Using a Disease Triangle Approach

Coccidioides immitis and Coccidioides posadasii are the etiological agents of coccidioidomycosis (Valley fever [VF]). Disease manifestation ranges from mild pneumonia to chronic or extrapulmonary infection. If diagnosis is delayed, the risk of severe disease increases. In this report, we investigated the intersection of pathogen, host, and environment for VF cases in Northern Arizona (NAZ), where the risk of acquiring the disease is much lower than in Southern Arizona. We investigated reported cases and assessed pathogen origin by comparing genomes of NAZ clinical isolates to isolates from other regions. Lastly, we surveyed regional soils for presence of Coccidioides. We found that cases of VF increased in NAZ in 2019, and Coccidioides NAZ isolates are assigned to Arizona populations using phylogenetic inference. Importantly, we detected Coccidioides DNA in NAZ soil. Given recent climate modeling of the disease that predicts that cases will continue to increase throughout the region, and the evidence presented in this report, we propose that disease awareness outreach to clinicians throughout the western United States is crucial for improving patient outcomes, and further environmental sampling across the western U.S. is warranted.

IMPORTANCE Our work is the first description of the Valley fever disease triangle in Northern Arizona, which addresses the host, the pathogen, and the environmental source in the region. Our data suggest that the prevalence of diagnosed cases rose in 2019 in this region, and some severe cases necessitate hospitalization. We present the first evidence of Coccidioides spp. in Northern Arizona soils, suggesting that the pathogen is maintained in the local environment. Until disease prevention is an achievable option via vaccination, we predict that incidence of Valley fever will rise in the area. Therefore, enhanced awareness of and surveillance for coccidioidomycosis is vital to community health in Northern Arizona.

Economic Burden of Fungal Diseases in the United States

We conservatively estimated the US economic burden of fungal diseases as $11.5 billion in 2019: direct medical costs ($7.5 billion), productivity loss due to absenteeism ($870 million), and premature deaths ($3.2 billion). An alternative "value of statistical life" approach yielded >$48 billion. These are likely underestimates given underdiagnosis and underreporting.

Δcps1 vaccine protects dogs against experimentally induced coccidioidomycosis

Coccidioidomycosis is a significant health problem of dogs and humans in endemic regions, especially California and Arizona in the U.S. Both species would greatly benefit from a vaccine to prevent this disease. A live avirulent vaccine candidate, Δcps1, was tested for tolerability and efficacy to prevent pulmonary coccidioidomycosis in a canine challenge model. Vaccine injection-site reactions were transient and there were no systemic effects observed. Six of seven vaccine sites tested and all draining lymph nodes were sterile post-vaccination. Following infection with Coccidioides posadasii, strain Silveira, arthroconidia into the lungs, dogs given primary and booster vaccinations had significantly reduced lung fungal burdens (P = 0.0003) and composite disease scores (P = 0.0002) compared to unvaccinated dogs. Dogs vaccinated once had fungal burdens intermediate between those given two doses or none, but disease scores were not significantly different from unvaccinated (P = 0.675). Δcps1 was well-tolerated in the dogs and it afforded a high level of protection when given as prime and boost. These results drive the Δcps1 vaccine toward a licensed veterinary vaccine and support continued development of this vaccine to prevent coccidioidomycosis in humans.

Sociodemographic factors associated with patients hospitalised for coccidioidomycosis in California and Arizona, State Inpatient Database 2005-2011

Coccidioidomycosis is endemic in the Southwestern United States. Disseminated infection can be life-threatening and is responsible for hospitalisation and significant healthcare resource utilisation. There are limited data evaluating factors associated with hospitalisation for coccidioidomycosis. We conducted a cross-sectional study to assess incidence and factors associated with coccidioidomycosis-associated hospitalisation in California and Arizona. We analysed hospital discharge data obtained from the State Inpatient Dataset for California and Arizona between 2005 and 2011 and performed multivariable logistic regression examining factors associated with coccidioidomycosis-associated hospitalisation. During our time frame, we found 23 758 coccidioidomycosis-associated hospitalisations. Coccidioidomycosis incidence was over sixfold higher in Arizona compared to California (198.9 vs. 29.6/100 000 person-years). In our multivariable model, coccidioidomycosis-associated hospitalisation was associated with age group 40-49 years (referent group: age 18-29 years, adjusted odds ratio (aOR) = 1.50 (95% confidence interval (CI) 1.43-1.59)), African American race (referent group: Caucasian, aOR = 1.98 (95% CI 1.89-2.06)), residing in a large rural town (referent group: urban area, aOR = 2.28 (95% CI 2.19-2.39)), uncomplicated diabetes (aOR = 1.47 (95% CI 1.41-1.52)) chronic obstructive pulmonary disease (aOR = 1.59 (95% CI 1.54-1.65)) and higher number of comorbidities (aOR = 1.02 (95% CI 1.02-1.03) for each point in the Elixhauser score). Identifying persons at highest risk for hospitalisation with coccidioidomycosis may be helpful for future prevention efforts.

Delays in Coccidioidomycosis Diagnosis and Associated Healthcare Utilization, Tucson, Arizona, USA

Tucson, Arizona, USA, is a highly coccidioidomycosis-endemic area. We conducted a retrospective review of 815 patients in Tucson over 2.7 years. Of 276 patients with coccidioidomycosis, 246 had a delay in diagnosis; median delay was 23 days. Diagnosis delay was associated with coccidioidomycosis-related costs totaling $589,053 and included extensive antibacterial drug use.

Expansion of Coccidioidomycosis Endemic Regions in the United States in Response to Climate Change

Coccidioidomycosis (Valley fever) is a fungal disease endemic to the southwestern United States. Across this region, temperature and precipitation influence the extent of the endemic region and number of Valley fever cases. Climate projections for the western United States indicate that temperatures will increase and precipitation patterns will shift, which may alter disease dynamics. We estimated the area potentially endemic to Valley fever using a climate niche model derived from contemporary climate and disease incidence data. We then used our model with projections of climate from Earth system models to assess how endemic areas will change during the 21st century. By 2100 in a high warming scenario, our model predicts that the area of climate-limited endemicity will more than double, the number of affected states will increase from 12 to 17, and the number of Valley fever cases will increase by 50%. The Valley fever endemic region will expand north into dry western states, including Idaho, Wyoming, Montana, Nebraska, South Dakota, and North Dakota. Precipitation will limit the disease from spreading into states farther east and along the central and northern Pacific coast. This is the first quantitative estimate of how climate change may influence Valley fever in the United States. Our predictive model of Valley fever endemicity may provide guidance to public health officials to establish disease surveillance programs and design mitigation efforts to limit the impacts of this disease.

Comparison of two FDA-cleared EIA assays for the detection of Coccidioides antibodies against a composite clinical standard

Coccidioidomycosis is a disease endemic to the southwestern United States, parts of Mexico, and Central and South America. Diagnosis of the disease is commonly delayed because of the lack of prompt testing and the dearth of reliable diagnostic tests. Culture and nucleic acid testing require a specimen, yet the typical patient presents with a dry cough and no sputum. Serologic methods depend on an effective antibody response by the patient, but antibody production may be unreliable or delayed until several weeks after initial symptom onset. Most published reports of serologic assays compare them to traditional serologic tests such as complement fixation and immunodiffusion. We sought to characterize the performance of two commercially available serologic tests, Meridian Premier and IMMY Omega, against a composite clinical reference standard to determine the sensitivity and specificity of these tests in detecting whether antibody is likely present in clinical specimens. The composite reference standard included symptoms, radiologic findings, and serologic results from complement fixation and immunodiffusion. For the Meridian test, sensitivity and specificity respectively were 69.4% and 95.4% for immunoglobulin G (Ig G) and 57.1% and 70.4% for immunoglobulin M (IgM). For the IMMY assay, sensitivity and specificity respectively were 53.1% and 96.7% for IgG and 34.7% and 85.5% for IgM.

Update on the Epidemiology of coccidioidomycosis in the United States

The incidence of reported coccidioidomycosis in the past two decades has increased greatly; monitoring its changing epidemiology is essential for understanding its burden on patients and the healthcare system and for identifying opportunities for prevention and education. We provide an update on recent coccidioidomycosis trends and public health efforts nationally and in Arizona, California, and Washington State. In Arizona, enhanced surveillance shows that coccidioidomycosis continues to be associated with substantial morbidity. California reported its highest yearly number of cases ever in 2016 and has implemented interventions to reduce coccidioidomycosis in the prison population by excluding certain inmates from residing in prisons in high-risk areas. Coccidioidomycosis is emerging in Washington State, where phylogenetic analyses confirm the existence of a unique Coccidioides clade. Additional studies of the molecular epidemiology of Coccidioides will improve understanding its expanding endemic range. Ongoing public health collaborations and future research priorities are focused on characterizing geographic risk, particularly in the context of environmental change; identifying further risk reduction strategies for high-risk groups; and improving reporting of cases to public health agencies.