Shawn Lockhart

• PhD, D(ABMM)
• Managing Director at Centers for Disease Control and Prevention

Chromoblastomycosis, a fungal neglected tropical disease, is acquired through traumatic inoculation and is clinically characterized by a chronic granulomatous infection of the skin and subcutaneous tissue. Fonsecaea pedrosoi is the most commonly reported etiologic agent globally. Itraconazole is considered first-line therapy, but successful treatme...

Background Infection by Cryptococcus gattii can lead to pulmonary or central nervous system (CNS) disease, or both. Whether the sites of infection and disease severity are associated with C. gattii species and lineages or with certain underlying medical conditions, or both is unclear. We conducted a retrospective cohort study to identify factors as...

Medically important pathogenic fungi invade vertebrate tissue and are considered primary when part of their nature life cycle is associated with an animal host and are usually able to infect immunocompetent hosts. Opportunistic fungal pathogens complete their life cycle in environmental habitats or occur as commensals within or on the vertebrate bo...

Background Blastomycosis is an environmentally acquired fungal infection that can result in severe pulmonary illness and high hospitalization rates. In 2023, a blastomycosis outbreak was detected among workers at a paper mill in Delta County, Michigan. Methods We included patients with clinical and laboratory evidence of blastomycosis who had spen...

Chromoblastomycosis, an implantation mycosis, is a neglected tropical disease that causes decreased quality of life, stigma, and disability. The global burden of disease is unknown and data on disease epidemiology and outcomes are severely limited by a lack of access to needed diagnostic tools and therapeutics. The World Health Organization outline...

Objectives Reported amphotericin B resistance rates for Candida auris vary considerably. This may reflect clinically relevant differences in susceptibility, technical issues with testing, or adoption of a clinical breakpoint that bisects the wild-type population. We compared reference methods and two gradient diffusion strips using a shared C. auri...

Antifungal-resistant dermatophyte infections have recently emerged as a global public health concern. A survey of US infectious diseases specialists found that only 65% had heard of this issue and just 39% knew how to obtain testing to determine resistance. Increased clinician awareness and access to testing for antifungal-resistant dermatophytosis...

Background Blastomycosis, coccidioidomycosis, and histoplasmosis are environmentally acquired fungal diseases that clinically resemble bacterial and viral community-acquired pneumonia and require laboratory testing for diagnosis. Patients frequently present to primary care and experience diagnostic delays when a fungal etiology is not initially sus...

Importance Trichophyton indotineae is an emerging dermatophyte causing outbreaks of extensive tinea infections often unresponsive to terbinafine. This species has been detected worldwide and in multiple US states, yet detailed US data on infections with T indotineae are sparse and could improve treatment practices and medical understanding of trans...

Background Reports of fluconazole-resistant Candida parapsilosis bloodstream infections are increasing. We describe a cluster of fluconazole-resistant C. parapsilosis bloodstream infections identified in 2021 on routine surveillance by the Georgia Emerging Infections Program in conjunction with the Centers for Disease Control and Prevention. Metho...

We describe a feline sporotrichosis cluster and zoonotic transmission between one of the affected cats and a technician at a veterinary clinic in Kansas, USA. Increased awareness of sporotrichosis and the potential for zoonotic transmission could help veterinary professionals manage feline cases and take precautions to prevent human acquisition.

Dermatophytoses are fungal infections of the skin, hair, and nails that affect approximately 25% of the global population. Occlusive clothing, living in a hot humid environment, poor hygiene, proximity to animals, and crowded living conditions are important risk factors. Dermatophyte infections are named for the anatomic area they infect, and inclu...

We describe a case of tinea genitalis in an immunocompetent woman in Pennsylvania, USA. Infection was caused by Trichophyton indotineae potentially acquired through sexual contact. The fungus was resistant to terbinafine (first-line antifungal) but improved with itraconazole. Clinicians should be aware of T. indotineae as a potential cause of antif...

Sporothrix brasiliensis is an emerging zoonotic fungal pathogen that can be difficult to treat. Antifungal susceptibility testing was performed on the mold phase of a convenience sample of 61 Sporothrix spp. isolates from human and cat sporotrichosis cases in Brazil using the Clinical and Laboratory Standards Institute standard M38. A bimodal distr...

CHROMagar Candida Plus is a new formulation of chromogenic media designed for the detection and differentiation of major clinical Candida species, including Candida auris . The objective of this study is to evaluate CHROMagar Candida Plus when used according to manufacturer’s instructions with a panel of 206 fungal isolates and 83 skin-swab specime...

Between September and November 2021, 5 snow leopards ( Panthera uncia) and 1 lion ( Panthera leo) were naturally infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) and developed progressive respiratory disease that resulted in death. Severe acute respiratory syndrome coronavirus 2 sequencing identified the delta variant in all cases...

Candida glabrata is one of the most common causes of systemic candidiasis, often resistant to antifungal medications. To describe the genomic context of emerging resistance, we conducted a retrospective analysis of 82 serially collected isolates from 33 patients from population-based candidemia surveillance in the United States. We used whole-genom...

Dermatophyte infections (a.k.a. ringworm, tinea) affect an estimated 20%–25% of the world’s population. In North America, most dermatophytoses are caused by Trichophyton rubrum or Trichophyton mentagrophytes species complexes. Severe and antifungal-resistant dermatophytoses are a growing global public health problem. A new species of the T. mentagr...

Background The World Health Organization (WHO) designates the implantation mycoses eumycetoma and chromoblastomycosis as Neglected Tropical Diseases. These infections usually develop after traumatic skin inoculation and primarily occur in resource-limited countries in tropical or subtropical areas. They are difficult to diagnose, may require prolon...

Background Since 2020, outbreaks of fluconazole-resistant Candida parapsilosis (FR-CP) infections have proliferated around the world. An increase in FR-CP bloodstream infections (BSI) in the Atlanta metropolitan area in 2021 was identified during routine surveillance through the Georgia Emerging Infections Program supported by the Centers for Disea...

The rapid pace of name changes of medically important fungi is creating challenges for clinical laboratories and clinicians involved in patient care. We describe two sources of name change which have different drivers, at the species versus the genus level. Some suggestions are made here to reduce the number of name changes. We urge taxonomists to...

Background: Candida auris is a multidrug-resistant yeast capable of invasive infection with high mortality and healthcare-associated outbreaks globally. Due to limited labratory capacity, the burden of C. auris is unknown in Bangladesh. We estimated the extent of C. auris colonization and infection among patients in Dhaka city intensive care units....

Background: Candida spp can cause a variety of infections known as candidiasis, ranging from severe invasive infections to superficial mucosal infections of the mouth and vagina. Fluconazole, a triazole antifungal, is commonly prescribed to treat candidiasis but increasing fluconazole resistance is a growing concern for several Candida spp. Althoug...

Background Public health officials are responding to an outbreak of fungal meningitis among patients who received procedures under epidural anesthesia at two clinics (River Side Surgical Center and Clinica K-3) in Matamoros, Mexico, during January 1–May 13, 2023. This report describes outbreak epidemiology and outlines interim diagnostic and treatm...

Candida auris has been recognized as an emerging multidrug-resistant pathogen with a significant public health burden, causing cases of invasive infection and colonization due to its persistence on inanimate surfaces, ability to colonize skin of some patients, and high transmissibility in healthcare settings. The first sporadic report of the isolat...

During recent decades, the emergence of pathogenic fungi has posed an increasing public health threat, particularly given the limited number of antifungal drugs available to treat invasive infections. In this Review, we discuss the global emergence and spread of three emerging antifungal-resistant fungi: Candida auris, driven by global health-care...

This chapter summarizes the comparative activities of the major systemic antifungal agents against important groups of fungi. It discusses the characteristics of the several other agents that can be used for the oral or parenteral treatment of superficial, subcutaneous, or systemic fungal infections. The allylamines are a group of synthetic antifun...

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 diseas...

Antibiotic and antifungal resistance (AR)—the ability of bacteria and fungi to defeat the drugs designed to kill them—is one of the greatest global public health challenges. Antibiotics and antifungals are among our most powerful tools for fighting life‐threatening infections. The threat of AR undermines progress in health care, food production, an...

Background: Candida auris is an emerging fungal threat that has been spreading in the United States since it was first reported in 2016. Objective: To describe recent changes in the U.S. epidemiology of C auris occurring from 2019 to 2021. Design: Description of national surveillance data. Setting: United States. Patients: Persons with any...

Candida haemulonii complex species can be multidrug-resistant (MDR) and cause infections such as candidemia. This study determined the genetic relationship between isolates from Brazil and the United States through whole-genome sequencing and performed antifungal susceptibility testing to investigate drug resistance. Contrary to what is widely desc...

Scedosporium spp. and Lomentospora prolificans are an emerging group of fungi refractory to current antifungal treatments. These species largely affect immunocompromised individuals but can also be lung colonizers in cystic fibrosis patients. Although Scedosporium apiospermum is thought to be the predominant species, the group has been expanded to...

Background Candidemia is a common healthcare-associated infection with high mortality. Estimates of recurrence range from 1%–17%. Few studies have focused on those with recurrent candidemia who often experience more severe illness and greater treatment failure. We describe recurrent candidemia trends and risk factors. Methods We analyzed populatio...

Azole resistance in Aspergillus fumigatus is a One Health resistance threat, where azole fungicide exposure compromises the efficacy of medical azoles. The use of the recently authorized fungicide iplufenoquin, which shares its mode-of-action with a new antifungal olorofim, underscores the need for risk assessment for dual use of antifungals.

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Objective The epidemic of antifungal-resistant dermatophytosis in India has been reported. These infections are associated with severe morbidity, resistance to oral itraconazole and terbinafine, and the widespread misuse of topical steroids. Trichophyton indotineae has emerged as the predomi...

Combination antifungal therapy is widely used but not well understood. We analyzed the spectrophotometric readings from a multicenter study conducted by the New York State Department of Health to further characterize the in vitro interactions of the major classes of antifungal agents against Candida spp. Loewe additivity-based fractional inhibitory...

Identification of the emerging multidrug-resistant yeast Candida auris is challenging. Here, we describe the role of the Mexico national reference laboratory Instituto de Diagnóstico y Referencia Epidemiológicos Dr. Manuel Martínez Báez (InDRE) and the Mexican national laboratory network in the identification of C. auris. Reference identification o...

We report a fatal infection in a 65-year-old immunocompromised male patient caused by pan-triazole-resistant Aspergillus fumigatus containing a TR34/L98H genetic mutation linked to agricultural fungicide use. Clinical and environmental surveillance of triazole-resistant A. fumigatus is needed in the United States to prevent spread and guide healthc...

Background Invasive mold diseases (IMD) cause severe illness, but public health surveillance data are lacking. We describe data collected from a laboratory-based, pilot IMD surveillance system. Methods During 2017–2019, the Emerging Infections Program conducted active IMD surveillance at three Atlanta-area hospitals. We ascertained potential cases...

Candida auris is an emerging yeast species that has the unique characteristics of patient skin colonization and rapid transmission within healthcare facilities and the ability to rapidly develop antifungal resistance. When C. auris first started appearing in clinical microbiology laboratories, it could only be identified using DNA sequencing. In th...

Candida glabrata is the second leading cause of candidemia in many countries and is one of the most concerning yeast species of nosocomial importance due to its increasing rate of antifungal drug resistance and emerging multidrug-resistant isolates. Application of multilocus sequence typing (MLST) to clinical C. glabrata isolates revealed an associ...

Candida and Cryptococcus affect millions of people yearly, being responsible for a wide array of clinical presentations, including life-threatening diseases. Interestingly, most human-pathogenic yeasts are not restricted to the clinical setting, as they are also ubiquitous in the environment. Recent studies raise concern regarding the potential imp...

Background Since the first report of Candida auris in 2016, the Colombian Instituto Nacional de Salud (INS) has implemented a national surveillance of the emerging multidrug-resistant fungus. Objectives This report summarizes the findings of this laboratory-based surveillance from March 2016 to December 2020. Results A total of 1,720 C. auris cas...

The Cryptococcus gattii species complex has often been referred to as a primary pathogen due to its high infection frequency among apparently immunocompetent patients. In order to scrutinize the immune status of patients and the lineages of etiologic agents, we analyzed patient histories and the molecular types of etiologic agents from 135 global C...

Aspergillus fumigatus is one of the most common causes of invasive mold infections in patients with immune deficiencies and has also been reported in patients with severe influenza and severe acute respiratory syndrome coronavirus 2 (SARs-CoV-2). Triazole drugs are the first line of therapy for this infection; however, their efficacy has been compr...

In contrast to a robust literature on known pathogenic fungi such as Cryptococcus and Aspergillus species that cause pulmonary infections, reports of the uncommon genus Sporopachydermia causing infections are very limited. We present the first case report describing the fungus, Sporopachydermia lactativora as a likely cause of pneumonia in a patien...

Fungal infections are a rising threat to our immunocompromised patient population as well as other non-immunocompromised patients with various medical conditions. However, little progress has been made in the past decade to improve fungal diagnostics. To jointly address this diagnostic challenge, the Fungal Diagnostics Laboratory Consortium (FDLC)...

Background The COVID-19 pandemic has resulted in unprecedented healthcare challenges, and COVID-19 has been linked to secondary infections. Candidemia, a fungal healthcare-associated infection, has been described in patients hospitalized with severe COVID-19. However, studies of candidemia and COVID-19 co-infection have been limited in sample size...

Background: Candidemia is a common opportunistic infection causing substantial morbidity and mortality. Because of an increasing proportion of non-albicans Candida species and rising antifungal drug resistance, the Infectious Diseases Society of America (IDSA) changed treatment guidelines in 2016 to recommend echinocandins over fluconazole as firs...

Cryptococcus gattii infection is a rare cause of severe pulmonary disease and meningoencephalitis that has only recently been detected in the southeastern United States. We describe organ transplant‐associated outbreak of C. gattii infection involving an HIV‐negative immunosuppressed donor in this region who died following new‐onset headache and se...

Olorofim is a novel antifungal drug that belongs to the orotomide drug class which inhibits fungal dihydroorotate dehydrogenase (DHODH), thus halting pyrimidine biosynthesis and ultimately DNA synthesis, cell growth and division. It is being developed at a time when many invasive fungal infections exhibit antifungal resistance or have limited treat...

We evaluated the CLSI M44ed3E disk diffusion method in comparison with the CLSI M27ed4 broth microdilution method for caspofungin and fluconazole and the Etest method for amphotericin B to categorize susceptibility of 347 clinical isolates of Candida auris . Utilizing the zone diameter cutoffs established here we observed the overall categorial agr...

The EORTC/MSGERC have revised the definitions for proven, probable, and possible fungal diseases. The tissue diagnosis subcommittee was tasked with determining how and when species can be determined from tissue in the absence of culture. The subcommittee reached a consensus decision that polymerase chain reaction (PCR) from tissue, but not immunohi...

Background Nikkomycin Z is a competitive inhibitor of chitin synthase—an enzyme needed for synthesis of the fungal cell wall. Nikkomycin Z shows promise as a treatment for coccidioidomycoses and mixed activity has been described against other fungi and yeast. To our knowledge, it has not previously been tested against the emerging fungal pathogen C...

Endemic fungi are thermally dimorphic fungi that have a limited geographic range and can cause both primary disease and opportunistic infections. The Americas are home to more genera of endemic fungi than anywhere else on earth. These include Coccidioides, Histoplasma, Blastomyces, Paracoccidioides, and Sporothrix. Endemic fungi are found across th...

Background: Diagnosis of invasive fungal infections from formalin-fixed paraffin-embedded (FFPE) tissues by PCR amplification is a developing technology. One of the difficulties of establishing a validated protocol for this testing is that the gold standard, culture, is much less sensitive than the test being validated. Objectives: To validate F...

Background Many U.S. clinical laboratories lack capacity to definitively identify fungi or perform antifungal susceptibility testing (AFST). To expand testing access, CDC’s Antibiotic Resistance Laboratory Network (AR Lab Network) provides Candida species identification and AFST to U.S. facilities for clinical and public health purposes. We describ...

Background Invasive mold infections (IMI) such as aspergillosis and mucormycosis are often fatal among immunocompromised patients and cause high-profile outbreaks. Public health surveillance for IMI is challenging; most epidemiologic studies are limited to transplant and cancer patients at greatest risk of IMI. The established Mycoses Study Group (...

Background Candidemia is a bloodstream infection commonly associated with high morbidity and mortality. Failure to clear candidemia can lengthen hospitalization and treatment. Factors associated with candidemia clearance are unknown. Methods We analyzed 2017 candidemia surveillance data from the Centers for Disease Control and Prevention’s Emergin...

To identify the prevalence of C. auris in Canadian patients who are potentially at risk for colonization, we screened 488 patients who were either hospitalized abroad, had a carbapenemase-producing organism (CPO), or were in units with high antifungal use. Two patients were colonized with C. auris; both had received healthcare in India and had a CP...

Background The pathogen Candida auris is rapidly gaining clinical importance because of its resistance to antifungal treatments and its persistence in hospital environments. Early and accurate diagnosis of C. auris infections is crucial, and however, the fungus has often been misidentified by commercial systems. Objectives To develop conventional...

On behalf of the Clinical and Laboratory Standards Institute (CLSI), the Expert Panel on Microbiology would like to respond to the recent commentary by Kirby and colleagues voicing concerns related to verification of commercial antimicrobial susceptibility testing (AST) for new drugs that are introduced into the clinical laboratory (1).…

Background: Candida auris is an emerging multidrug-resistant yeast that causes outbreaks in healthcare settings around the world. In 2016, clinicians and public health officials identified patients with C. auris bloodstream infections (BSI) in Colombian healthcare facilities. To evaluate potential risk factors and outcomes for these infections, we...

Purpose of Review This review highlights innovative approaches for histoplasmosis detection using laboratory technologies published in the past 6 years. Recent Findings Microscopy and culture are the gold standards for confirming the diagnosis of histoplasmosis, but these can be slow, and their sensitivity and specificity can vary. It is well know...

Candida auris is an emerging multidrug-resistant fungal pathogen reported worldwide. Infections due to C. auris are usually nosocomial and associated with high rates of fluconazole resistance and mortality. Echinocandins are utilized as the first-line treatment. However, echinocandins are only available intravenously and are associated with increas...

The recent emergence of a multidrug-resistant yeast, Candida auris, has drawn attention to the closely related species from the Candida haemulonii complex that include C. haemulonii, Candida duobushaemulonii, Candida pseudohaemulonii, and the recently identified Candida vulturna. Here, we used antifungal susceptibility testing and whole-genome sequ...

Candida auris is an emerging multidrug-resistant pathogen of global concern, known to be responsible for outbreaks on six continents and to be commonly resistant to antifungals. While the vast majority of clinical C. auris isolates are highly resistant to fluconazole, an essential part of the available antifungal arsenal, very little is known about...

Background: Candida auris is an emerging multidrug-resistant yeast that can cause invasive infections and healthcare-associated outbreaks. Here, we describe 34 cases of pediatric C. auris bloodstream infections (BSIs) identified during July 2014-October 2017 in 2 hospitals in Colombia. Methods: We conducted a retrospective review of microbiology...

Rhizopus spp. fungi are ubiquitous in the environment and a rare but substantial cause of infection in immunosuppressed persons and surgery patients. During 2005-2017, an abnormally high number of Rhizopus infections in surgery patients, with no apparent epidemiologic links, were reported in Argentina. To determine the likelihood of a common source...

Although not as ubiquitous as antibacterial susceptibility testing, antifungal susceptibility testing (AFST) is a tool of increasing importance in clinical microbiology laboratories. The goal of AFST is to reliably produce MIC values that may be used to guide patient therapy, inform epidemiological studies, and track rates of antifungal drug resist...

In less than a decade, C. auris has emerged in health care settings worldwide; this species is capable of colonizing skin and causing outbreaks of invasive candidiasis. In contrast to other Candida species, C. auris is unique in its ability to spread via nosocomial transmission and its high rates of drug resistance. As part of the public health res...

Introduction: The prevalence of azole resistance in C. parapsilosis is very low in most parts of the world. However, South Africa has reported an exceptionally high prevalence of azole resistance in C. parapsilosis strains isolated from candidaemia cases. We aimed to determine the possible molecular mechanisms of fluconazole resistance in C. parap...

We report the first case of Acrophialophora levis causing cerebral phaeohyphomycosis in a solid organ transplantation recipient. A. levis is a rare cause of invasive dematiaceous fungal infection among immunocompromised persons. We describe the clinical course of a kidney transplant patient who presented with acute hemiplegia due to a brain abscess...

Candida auris has emerged as a multidrug-resistant pathogen of great clinical concern. Approximately 90% of clinical C. auris isolates are resistant to fluconazole, the most commonly prescribed antifungal agent, yet it remains unknown what mechanisms underpin this fluconazole resistance. To identify novel mechanisms contributing to fluconazole resi...

Candida auris has emerged globally as a multidrug-resistant yeast that can spread via nosocomial transmission. An initial phylogenetic study of isolates from Japan, India, Pakistan, South Africa, and Venezuela revealed four populations (Clades I, II, III, and IV) corresponding to these geographic regions. Since this description, C. auris has been r...

Aspergillosis is one of the most common fungal infections. The predominant cause of aspergillosis is the species Aspergillus fumigatus. There have been increasing reports of A. fumigatus isolates that are resistant to azole antifungals. The predominant causes of this resistance are environmentally acquired mutations in the target gene, CYP51A, know...

Background. Invasive fungal diseases (IFDs) remain important causes of morbidity and mortality. The consensus definitions of the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group have been of immense value to researchers who conduct clinical trials of antifungals, assess diagnost...

Background: Invasive fungal diseases (IFDs) remain important causes of morbidity and mortality. The consensus definitions of the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group have been of immense value to researchers who conduct clinical trials of antifungals, assess diagnos...

Candida auris is an emerging multidrug-resistant fungal pathogen. Since first reported in 2009, C. auris has caused healthcare outbreaks around the world, often involving high mortality. Identification of C. auris has been a major challenge as many common conventional laboratory methods cannot accurately detect it. Early detection and implementatio...

Introduction Candida auris is an emerging multidrug-resistant yeast that has been systematically incorrectly identified by phenotypic methods in clinical microbiology laboratories. VITEK®2 automated identification system (bioMérieux) recently included C. auris in its database (version 8.01). Material and methods We evaluated the performance of VITE...

Ibrexafungerp is a first in class glucan-synthase inhibitor. In vitro activity was determined for 89 Candida glabrata isolates with molecularly identified FKS1 or FKS2 mutations conferring resistance to the echinocandins. All isolates were resistant to at least one echinocandin (i.e., anidulafungin, caspofungin, and micafungin) by broth microdiluti...

Problem/condition: Candidemia is a bloodstream infection (BSI) caused by yeasts in the genus Candida. Candidemia is one of the most common health care-associated BSIs in the United States, with all-cause in-hospital mortality of up to 30%. Period covered: 2012-2016. Description of system: CDC's Emerging Infections Program (EIP), a collaboratio...

Candida auris is an emerging, multi-drug resistant, health care-associated fungal pathogen. Its predominant prevalence in hospitals and nursing homes indicates its ability to adhere to and colonize the skin, or persist in an environment outside the host—a trait unique from other Candida species. Besides being associated globally with life-threateni...

Background: Two species complexes (SC) cause the majority of human Cryptococcus infections: Cryptococcus neoformans SC and Cryptococcus gattii SC. Infection is typically thought to be acquired following environmental exposure. In an urban setting, parks and other public spaces are a likely source of contact with C. gattii SC. Objectives: The goa...

This report serves as a guide for investigating mucormycosis infections in healthcare. We describe lessons learned from previous outbreaks and offer methods and tools that can aid in these investigations. We also offer suggestions for conducting environmental assessments, implementing infection control measures, and initiating surveillance to ensur...