Surveillance for Coccidioidomycosis, Histoplasmosis, and Blastomycosis - United States, 2019

Tracing histoplasmosis genomic epidemiology and species occurrence across the USA

ABSTRACTHistoplasmosis is an endemic mycosis in North America frequently reported along the Ohio and Mississippi River Valleys, although autochthonous cases occur in non-endemic areas. In the United States, the disease is provoked by two genetically distinct clades of Histoplasma capsulatum sensu lato, Histoplasma mississippiense (Nam1) and H. ohiense (Nam2). To bridge the molecular epidemiological gap, we genotyped 93 Histoplasma isolates (62 novel genomes) including clinical, environmental, and veterinarian samples from a broader geographical range by whole-genome sequencing, followed by evolutionary and species niche modelling analyses. We show that histoplasmosis is caused by two major lineages, H. ohiense and H. mississippiense; with sporadic cases caused by H. suramericanum in California and Texas. While H. ohiense is prevalent in eastern states, H. mississipiense was found to be prevalent in the central and western portions of the United States, but also geographically overlapping in some areas suggesting that these species might co-occur. Species Niche Modelling revealed that H. ohiense thrives in places with warmer and drier conditions, while H. mississippiense is endemic to areas with cooler temperatures and more precipitation. In addition, we predicted multiple areas of secondary contact zones where the two species co-occur, potentially facilitating gene exchange and hybridization. This study provides the most comprehensive understanding of the genomic epidemiology of histoplasmosis in the USA and lays a blueprint for the study of invasive fungal diseases.

Improving Coccidioidomycosis Testing for Emergency Department Patients With Suspect Community-Acquired Pneumonia: Analysis of Provider Attitudes and the Effect of a Targeted Intervention

Coccidioidomycosis is a common cause of community-acquired pneumonia in endemic regions. Approximately 20 000 cases of coccidioidomycosis occur annually; however, this statistic is limited by a widespread lack of testing. Here, we analyze emergency medicine provider attitudes toward coccidioidal testing and assess the effect of an intervention to improve testing rates.

Global incidence and mortality of severe fungal disease

Current estimates of fungal disease incidence and mortality are imprecise. Population at risk denominators were used to estimate annual incidence for 2019-21. Extensive literature searches from 2010 to 2023 were combined with over 85 papers on individual country and global disease burden. Crude and attributable mortality were estimated using a combination of untreated mortality, the proportion of patients who are treated, and percentage survival in treated patients. Awareness, guidelines, and accessibility of diagnostics and therapies informed the ratio of treated to untreated cases. Estimates do not include influenza or COVID-19 outbreaks. Data from more than 120 countries were included. Annually, over 2 113 000 people develop invasive aspergillosis in the context of chronic obstructive pulmonary disease, intensive care, lung cancer, or haematological malignancy, with a crude annual mortality of 1 801 000 (85·2%). The annual incidence of chronic pulmonary aspergillosis is 1 837 272, with 340 000 (18·5%) deaths. About 1 565 000 people have a Candida bloodstream infection or invasive candidiasis each year, with 995 000 deaths (63·6%). Pneumocystis pneumonia affects 505 000 people, with 214 000 deaths (42·4%). Cryptococcal meningitis affects 194 000 people, with 147 000 deaths (75·8%). Other major life-threatening fungal infections affect about 300 000 people, causing 161 000 deaths (53·7%). Fungal asthma affects approximately 11·5 million people and might contribute to 46 000 asthma deaths annually. These updated estimates suggest an annual incidence of 6·5 million invasive fungal infections and 3·8 million deaths, of which about 2·5 million (68%; range 35-90) were directly attributable.

Clinical Testing Guidance for Coccidioidomycosis, Histoplasmosis, and Blastomycosis in Patients With Community-Acquired Pneumonia for Primary and Urgent Care Providers

Coccidioidomycosis, histoplasmosis, and blastomycosis are underrecognized and frequently misdiagnosed fungal infections that can clinically resemble bacterial and viral community-acquired pneumonia. This guidance is intended to help outpatient clinicians test for these fungal diseases in patients with community-acquired pneumonia to reduce misdiagnoses, unnecessary antibacterial use, and poor outcomes.

Challenges Facing Antimicrobial Stewardship Programs in the Endemic Region for Coccidioidomycosis

Coccidioidomycosis poses a significant cost and morbidity burden in the United States. Additionally, coccidioidomycosis requires constant decision-making related to prevention, diagnosis, and management. Delays in diagnosis lead to significant consequences, including unnecessary diagnostic workup and antibacterial therapy. Antifungal stewardship considerations regarding empiric, prophylactic, and targeted management of coccidioidomycosis are also complex. In this review, the problems facing antimicrobial stewardship programs (ASPs) in the endemic region for coccidioidomycosis, consequences due to delayed or missed diagnoses of coccidioidomycosis on antibacterial prescribing, and excess antifungal prescribing for prevention and treatment of coccidioidomycosis are elucidated. Finally, our recommendations and research priorities for ASPs in the endemic region for coccidioidomycosis are outlined.

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.

Surveillance for Coccidioidomycosis, Histoplasmosis, and Blastomycosis During the COVID-19 Pandemic - United States, 2019-2021

Coccidioidomycosis, histoplasmosis, and blastomycosis are lower respiratory tract fungal infections whose signs and symptoms can resemble those of other respiratory illnesses, including pneumonia caused by bacterial or viral etiologies; this overlap in clinical presentation might lead to missed or delayed diagnoses. The causative fungi live in the environment, often in soil or plant matter. To describe the epidemiologic characteristics of cases of coccidioidomycosis, histoplasmosis, and blastomycosis during the COVID-19 pandemic, CDC analyzed case surveillance data for 2019-2021. During this period, a total of 59,655 coccidioidomycosis cases, 3,595 histoplasmosis cases, and 719 blastomycosis cases were reported to CDC. In 2020, fewer cases of each disease occurred in spring compared with other seasons, and most cases occurred in fall; national seasonality is not typically observed, and cases were seasonally distributed more evenly in 2019 and 2021. Fewer cases coinciding with the start of the COVID-19 pandemic, along with an unusually high blastomycosis case fatality rate in 2021 (17% compared with more typical rates of 8%-10%), suggest that the pandemic might have affected patients' health care-seeking behavior, public health reporting practices, or clinical management of these diseases. Increased awareness and education are needed to encourage health care providers to consider fungal diseases and to identify pneumonia of fungal etiology. Standardized diagnostic guidance and informational resources for fungal testing could be incorporated into broader respiratory disease awareness and preparedness efforts to improve early diagnosis of coccidioidomycosis, histoplasmosis, and blastomycosis.

A Diagnostic Approach to Fungal Pneumonia: An Infectious Diseases Perspective

Although bacteria significantly exceed fungi as the most common cause of lower respiratory tract infection, the incidence of fungal pneumonia is increasing because of a growing at-risk population of immunocompromised individuals as well as anthropogenic global heating and environmental disruption. When a patient presents with a clinical syndrome of pneumonia, a constellation of factors must be considered to determine the probability of a fungal pneumonia, including host factors, epidemiologic exposures, suggestive radiographic patterns, and the presence of a non-resolving pneumonia. In addition, knowledge of clinically important fungal pathogens, their epidemiology, and associated clinical syndromes are key in guiding appropriate diagnostic testing and result interpretation, and ultimately rendering a correct diagnosis of a fungal pneumonia. This article aims to provide a framework for the evaluation and appropriate diagnostic testing of patients with suspected fungal pneumonia.

Using Insurance Claims Data to Estimate Blastomycosis Incidence, Vermont, USA, 2011-2020

The epidemiology of blastomycosis in Vermont, USA, is poorly understood. Using insurance claims data, we estimated the mean annual blastomycosis incidence was 1.8 patients/100,000 persons during 2011-2020. Incidence and disease severity were highest in north-central counties. Our findings highlight a need for improved clinical awareness and expanded surveillance.

Valley Fever: Pathogenesis and Evolving Treatment Options

Coccidioidomycosis, also termed Valley fever, is a fungal infection caused by the inhalation of Coccidioides endospores. Once inhaled by a human host, the arthroconidia endospores travel to the lungs' alveoli to transform into spherules that grow and rupture to release more endospores. In the host immune response, macrophages, neutrophils, and dendritic cells will recognize the fungal antigen, producing pro-inflammatory cytokine. Th2 lymphocytes (type 2 helper T cells) are theorized to be the main human defense against Coccidioides given that Th2 deficiency is seen in patients with disseminated forms of the disease. A common triad of symptoms of coccidioidomycosis, also called "desert rheumatism," include fever, erythema nodosum, and arthralgia, often accompanied by a respiratory problem. In a clinical setting, along with the evaluation of symptoms, a medical provider may also test the patient's blood using antibody tests or perform microscopy to directly detect the presence of Coccidioides in a patient tissue sample for confirmation of a diagnosis. Imaging modalities may also be used to determine lung involvement and assess disease progression. A majority of coccidioidomycosis cases do not require specific treatment and will resolve on their own, so an approach with symptomatic treatment in mind is appropriate. If symptoms do not resolve, azoles or amphotericin B may be used, with the standard drug of choice being fluconazole (Diflucan, Pfizer, New York, New York, United States). Treatment varies depending on the immunocompetency of the patient. To name a few, pregnant patients and those with history of human immunodeficiency virus (HIV) or transplantation require special considerations.

Blastomycosis-Associated Hospitalizations, United States, 2010-2020

BACKGROUND

Blastomycosis is an environmentally acquired fungal disease that can cause severe illness, with approximately 65% of reported cases requiring hospitalization. Recent trends in blastomycosis-associated hospitalizations in the United States have not been described.

METHODS

We analyzed hospital discharge data from the Healthcare Cost and Utilization Project (HCUP) National (Nationwide) Inpatient Sample. We calculated hospitalization rates per 100,000 population using U.S. census data and examined factors associated with in-hospital mortality.

RESULTS

An estimated 11,776 blastomycosis-associated hospitalizations occurred during 2010-2020 (average yearly rate 0.3 per 100,000 persons), with no apparent temporal trend. Rates were consistently highest among persons ≥65 years old and males. In-hospital death occurred in 7.9% and approximately doubled from 3.9% in 2010 to 8.5% in 2020. Older age, chronic obstructive pulmonary disease, and malignancy were associated with mortality.

CONCLUSIONS

Blastomycosis-associated hospitalizations can result in poor outcomes, underscoring the continued need for attention to early detection and treatment of blastomycosis and monitoring of disease trends.

Public Health Research Priorities for Fungal Diseases: A Multidisciplinary Approach to Save Lives

Fungal infections can cause severe disease and death and impose a substantial economic burden on healthcare systems. Public health research requires a multidisciplinary approach and is essential to help save lives and prevent disability from fungal diseases. In this manuscript, we outline the main public health research priorities for fungal diseases, including the measurement of the fungal disease burden and distribution and the need for improved diagnostics, therapeutics, and vaccines. Characterizing the public health, economic, health system, and individual burden caused by fungal diseases can provide critical insights to promote better prevention and treatment. The development and validation of fungal diagnostic tests that are rapid, accurate, and cost-effective can improve testing practices. Understanding best practices for antifungal prophylaxis can optimize prevention in at-risk populations, while research on antifungal resistance can improve patient outcomes. Investment in vaccines may eliminate certain fungal diseases or lower incidence and mortality. Public health research priorities and approaches may vary by fungal pathogen.

Seasonality of sporotrichosis in Brazil: A modelled analysis of the epidemic in São Paulo, 2011-2020

BACKGROUND

Sporotrichosis is an endemic subcutaneous mycosis classically caused by the Sporothrix schenckii species complex. Recently, sporotrichosis has emerged in Brazil as a cat-transmitted epidemic caused by a new species, Sporothrix brasiliensis.

OBJECTIVES

To survey the clinical-epidemiological profile of all sporotrichosis cases diagnosed between 2011 and 2020 at a reference hospital in São Paulo metropolitan area and evaluate the annual distribution of cases in relation to seasonality.

METHODS

Patients' demographic and clinical-epidemiological data were surveyed. A generalized linear model was fitted to relate the quarterly number of sporotrichosis cases detected between 2015 and 2019 with precipitation and temperature series. Prediction of the number of cases from 2011 to 2014 was attempted based on the fitted model without the trend component that appears from 2015.

RESULTS

Among 271 suspected cases admitted during 2011-2020, 254 were confirmed by fungal isolation and/or clinical-epidemiological criteria. We observed that 2015 onwards the number of cases regularly increased during Autumn and Winter, the driest and coldest stations of the year. We verified that temperature series affected the number of cases (p = .005) because an increase of 1°C in the temperature series was associated with a 14.24% decrease in the average cases number, with the average number of cases increasing by 10.96% (p < .0001) every quarter, corresponding to an annual increase of 52%. Between 2011 and 2014, the predicted number of sporotrichosis cases averaged 10-12 per year, with 33%-38% occurring in the winter.

CONCLUSION

We hypothesize that sporotrichosis seasonality is associated with the felines' oestrus cycle, which may provide alternative, cat-directed approaches to the sporotrichosis epidemic control.

Traveling Does More Than Widen One's Horizon: Travel History as Key to Diagnosing Blastomycosis

This case report highlights the importance of a detailed travel history and the need to revisit the differential diagnosis when there is an unexpected clinical course. A previously healthy 15-year-old male presented to a hospital in Florida with a fever, cough, and shortness of breath. He was seen multiple times at urgent care centers and treated with steroids and antibiotics for community-acquired pneumonia (CAP). The patient's chest X-rays and CT showed necrotizing pneumonia with pleural effusion, which required a chest tube. Despite broadening coverage for possible resistant organisms, his fevers and hypoxia continued. On day 14 of hospitalization, a bronchoscopy was performed, which led to the diagnosis of blastomycosis. History was revisited, and a specific travel history was obtained. The patient had been camping with his father on the Minnesota/Canada border a few months prior to his presentation. Blastomycosis is caused by a dimorphic fungus endemic in certain parts of the United States including areas surrounding the Mississippi and Ohio River valleys, some southeastern states, and areas bordering the Great Lakes. Autochthonous blastomycosis is not seen in Florida. The infection is acquired by inhalation of the organism and is associated with outdoor occupation and recreation. As with other infections with specific endemic distribution, the diagnosis of blastomycosis can be delayed if the epidemiologic link is not established. Questions about travel history need to be very specific as this could be critical in establishing the appropriate differential diagnosis and leading the workup. The patient's lack of improvement despite appropriate antibiotic therapy for CAP led to questioning the working diagnosis, revisiting the history, and expanding the workup, which was critical in this case.

Race and ethnicity: Risk factors for fungal infections?

Racial and ethnic identities, largely understood as social rather than biologic constructs, may impact risk for acquiring infectious diseases, including fungal infections. Risk factors may include genetic and immunologic differences such as aberrations in host immune response, host polymorphisms, and epigenomic factors stemming from environmental exposures and underlying social determinants of health. In addition, certain racial and ethnic groups may be predisposed to diseases that increase risk for fungal infections, as well as disparities in healthcare access and health insurance. In this review, we analyzed racial and ethnic identities as risk factors for acquiring fungal infections, as well as race and ethnicity as they relate to risk for severe disease from fungal infections. Risk factors for invasive mold infections such as aspergillosis largely appear related to environmental differences and underlying social determinants of health, although immunologic aberrations and genetic polymorphisms may contribute in some circumstances. Although black and African American individuals appear to be at high risk for superficial and invasive Candida infections and cryptococcosis, the reasons for this are unclear and may be related to underling social determinants of health, disparities in access to healthcare, and other socioeconomic disparities. Risk factors for all the endemic fungi are likely largely related to underlying social determinants of health, socioeconomic, and health disparities, although immunologic mechanisms likely play a role as well, particularly in disseminated coccidioidomycosis.