Coccidioidomycosis Cases at a Regional Referral Center, West Texas, USA, 2013–2019

Overview of the Current Challenges in Pulmonary Coccidioidomycosis

Coccidioidomycosis is a disease caused by soil fungi of the genus Coccidioides, divided genetically into Coccidioides immitis (California isolates) and Coccidioides posadasii (isolates outside California). Coccidioidomycosis is transmitted through the inhalation of fungal spores, arthroconidia, which can cause disease in susceptible mammalian hosts, including humans. Coccidioidomycosis is endemic to the western part of the United States of America, including the central valley of California, Arizona, New Mexico, and parts of western Texas. Cases have been reported in other regions in different states, and endemic pockets are present in these states. The incidence of reported cases of coccidioidomycosis has notably increased since it became reportable in 1995. Clinically, the infection ranges from asymptomatic to fatal disease due to pneumonia or disseminated states. The recognition of coccidioidomycosis can be challenging, as it frequently mimics bacterial community-acquired pneumonia. The diagnosis of coccidioidomycosis is frequently dependent on serologic testing, the results of which can take several days or longer to obtain. Coccidioidomycosis continues to present challenges for clinicians, and suspected cases can be easily missed. The challenges of coccidioidomycosis disease, from presentation to diagnosis to treatment, remain a hurdle for clinicians, and further research is needed to address these challenges.

Coccidioidomycosis-Related Hospital Visits, Texas, USA, 2016-2021

We analyzed hospital discharge records of patients with coccidioidomycosis-related codes from the International Classification of Diseases, 10th revision, Clinical Modification, to estimate the prevalence of hospital visits associated with the disease in Texas, USA. Using Texas Health Care Information Collection data for 2016-2021, we investigated the demographic characteristics and geographic distribution of the affected population, assessed prevalence of hospital visits for coccidioidomycosis, and examined how prevalence varied by demographic and geographic factors. In Texas, 709 coccidioidomycosis-related inpatient and outpatient hospital visits occurred in 2021; prevalence was 3.17 cases per 100,000 total hospital visits in 2020. Geographic location, patient sex, and race/ethnicity were associated with increases in coccidioidomycosis-related hospital visits; male, non-Hispanic Black, and Hispanic patients had the highest prevalence of coccidioidomycosis compared with other groups. Increased surveillance and healthcare provider education and outreach are needed to ensure timely and accurate diagnosis and treatment of coccidioidomycosis in Texas and elsewhere.

Coccidioidomycosis in Oklahoma: A retrospective case series

BACKGROUND

Coccidioidomycosis is a systemic fungal disease endemic to arid regions of the Western Hemisphere. In the south-western US, Coccidioides spp. may account for up to 20%-25% of all cases of community acquired pneumonia. Clinical manifestations vary widely, from asymptomatic infection to life-threatening disease, especially in immunocompromised hosts.

OBJECTIVES

The primary objective of the study was to characterise cases of coccidioidomycosis in an area of the United States not considered traditionally endemic for the disease.

METHODS

We performed a single-centre retrospective study of all cases of coccidioidomycosis from 1 January 2000 to 31 December 2020, in the University of Oklahoma Health Sciences Medical Center.

RESULTS

A total of 26 patients were included for analysis. The central nervous system (CNS) and the lungs were the sites most frequently involved. Twenty (77%) had travelled to a coccidioidomycosis endemic region. Most were male (81%) with a median age of 42 years (range: 3-78 years). The majority (46%) were Caucasians, 19% were African American, 19% Hispanic, and 12% Native American. The most common comorbidities were diabetes mellitus and acquired immunodeficiency syndrome, identified in 27% and 23% of patients, respectively. Patients on immunosuppressive therapy accounted for 12% of all cases.

CONCLUSION

Our study is one of the largest single-centre case series of coccidioidomycosis from a non-endemic area. Diabetes mellitus was the most frequent comorbidity. Compared to other case series of coccidioidomycosis, our patient population had higher rates of immunosuppression and had both a higher rate of disseminated disease and overall mortality.

The dog as a sentinel and animal model for coccidioidomycosis

Coccidioidomycosis is a potentially fatal fungal disease of humans and animals that follows inhalation of Coccidioides spp. arthroconidia in the environment. The disease in dogs resembles that in people, and because dogs may be at increased risk of exposure due to their proximity to the ground and digging behavior, they are valuable models for the disease in humans. Dogs have been sentinels for identification of new regions of endemicity in Washington and Texas. Canine serosurveillance has also been used to predict variables associated with environmental presence of Coccidioides spp. Expansion of the endemic region of coccidioidomycosis with climate change-along with predicted population increases and increased development in the southwest United States-may result in 45.4 million additional people at risk of infection by 2090. Here we provide an overview of the value of dogs as sentinels for the disease and encourage the routine reporting of coccidioidomycosis cases in dogs to public health agencies. We also highlight the value of dogs as naturally occurring models for studying novel treatment options and preventatives, such as a novel live avirulent coccidioidomycosis vaccine.

Improving Early Recognition of Coccidioidomycosis in Urgent Care Clinics: Analysis of an Implemented Education Program

Background

Only 0.2% of coccidioidomycosis (CM) diagnoses were made in patients (pts) with pneumonia (PNA) in urgent care (UC), because they were not being tested for CM. Our objective in this study was to improve CM testing rates.

Methods

This was a time series of clinician practice before and after an intervention that occurred at UC clinics in Phoenix and Tucson Arizona. All patients in UC were >18 years old. We included information about CM in periodic educational activities for clinicians. Coccidioidal serologic testing (CST), CST results, and their relation to International Classification of Diseases, Tenth Revision (ICD-10) codes were extracted from medical records.

Results

Urgent care received 2.1 million visits from 1.5 million patients. The CST orders per 10⁴ visits increased from 5.5 to 19.8 (P < .0001). Percentage positive CSTs were highest for August, November, and December (17.0%) versus other months (10.6%). Positive CSTs were associated with PNA ICD-10 codes, and, independently, for Erythema nodosum (EN) which had the highest positivity rate (61.4%). Testing of PNA pts increased on first visits and on second visits when the first CST was negative. Yearly rates of PNA due to CM ranged from 17.3% to 26.0%. Despite this improvement, CST was still not done for over three quarters of pts with PNA. This was a noncomparative study.

Conclusions

Routine quality improvement activities have significantly but only partially improved rates of testing pts with PNA for CM in UC clinics located in a highly endemic area. Innovative strategies may be needed to improve current practice. Also in our region, EN, independent of PNA, is a strong predictor of CM.

Advocating for Coccidioidomycosis to Be a Reportable Disease Nationwide in the United States and Encouraging Disease Surveillance across North and South America

Coccidioidomycosis (Valley fever) has been a known health threat in the United States (US) since the 1930s, though not all states are currently required to report disease cases. Texas, one of the non-reporting states, is an example of where both historical and contemporary scientific evidence define the region as endemic, but we don't know disease incidence in the state. Mandating coccidioidomycosis as a reportable disease across more US states would increase disease awareness, improve clinical outcomes, and help antifungal drug and vaccine development. It would also increase our understanding of where the disease is endemic and the relationships between environmental conditions and disease cases. This is true for other nations in North and South America that are also likely endemic for coccidioidomycosis, especially Mexico. This commentary advocates for US state and territory epidemiologists to define coccidioidomycosis as a reportable disease and encourages disease surveillance in other endemic regions across North and South America in order to protect human health and reduce disease burden.