Articles from Emerging Infectious Diseases

Neisseria gonorrhoeae bacteria cause ≈82 million infections annually worldwide. As antimicrobial resistance (AMR) accelerates, the actual prevalence of antimicrobial-resistant infections remains obscured because of fragmented, heterogeneous, and often absent surveillance systems. The efficacy of ceftriaxone, widely used as first-line therapy, is increasingly threatened by the expansion of strains harboring the mosaic penA 60.001 allele, first documented in 2015 and now recognized globally as the dominant determinant of AMR. Our systematic search of the published literature identified 212 such isolates; nearly half were detected after 2022 in England and Australia, and epidemiologic data frequently linked acquisition of infection to the Asia-Pacific region. The substantially higher case numbers reported in those countries reflect the strength of their gonococcal AMR surveillance systems and more timely public data sharing. Our findings suggest that underreporting of the actual prevalence of ceftriaxone resistance is likely and that the opportunity for action is limited.

Anaplasmosis, an emerging tickborne zoonosis, infrequently involves the central nervous system, and cerebrospinal fluid (CSF) profiles of anaplasmosis remain poorly characterized. We conducted a multisite retrospective study of patients hospitalized with anaplasmosis during November 1, 2014–November 29, 2024, in Minnesota and Wisconsin, USA, a hyperendemic region. Included patients had anaplasmosis confirmed by PCR on blood samples, exhibited neurologic symptoms, and had lumbar puncture procedures. Ten hospitalized patients met inclusion criteria, 6 with meningitis, 3 with meningoencephalitis, and 1 with encephalitis. CSF findings were within reference ranges for 5 patients; 4 patients demonstrated mild lymphocytic pleocytosis, but glucose and protein levels were within reference ranges. One patient underwent a traumatic lumbar puncture resulting in neutrophilic pleocytosis. CSF abnormalities did not correlate with neurologic severity, suggesting a cytokine-mediated process rather than direct central nervous system infection. All patients rapidly improved with doxycycline, highlighting the need for early recognition and empiric therapy for anaplasmosis.

Carbapenem-resistant Enterobacterales (CRE) are a major global health threat with limited treatment options. Aztreonam/avibactam is a promising therapy against metallo-β-lactamase (MBL)–producing and other CRE, but emerging resistance threatens its effectiveness. Insertions in penicillin-binding protein 3 (PBP3), which are well described in Escherichia coli, are linked to reduced aztreonam/avibactam susceptibility but remain poorly characterized in Klebsiella pneumoniae. We report clinical K. pneumoniae carbapenemase–producing K. pneumoniae sequence type 11 isolates carrying a novel PBP3 YRIT insertion, conferring reduced susceptibility to aztreonam/avibactam and ceftazidime/avibactam. Functional and genetic studies suggest that the PBP3 insertion impairs β-lactam binding and, in combination with bla_KPC-2 and other β-lactamases, contributes to reduced susceptibility. Those findings demonstrate the emergence of a PBP3 insertion in a high-risk K. pneumoniae clone, underscoring the expansion of this resistance mechanism and the critical need for genomic surveillance and novel therapeutics to identify and treat such infections.

Chicago Department of Public Health identified 3 pediatric patients hospitalized with group A Streptococcus (GAS) disease during October 26–November 3, 2023, in a large congregate family migrant shelter in Chicago, Illinois, USA. One patient had invasive GAS infection; 2 had peritonsillar abscesses requiring drainage. Despite infection control measures, GAS pharyngitis cases continued through November 13. Chicago Department of Public Health coordinated clinical partners to perform rapid antigen detection testing and throat cultures for residents and staff with pharyngitis symptoms. During November 20, 2023–January 3, 2024, a total of 428 symptomatic persons were evaluated; 166 tested positive for GAS. Among persons with GAS pharyngitis, median age was 12 years (range 0–45 years); 54.2% were women and girls. Common symptoms included sore throat (87.3%) and fever (63.3%). One pediatric resident death caused by invasive GAS was confirmed postmortem. This response highlights outbreak challenges in large congregate shelters housing children.

Since 2023, there have been 3 outbreaks of toxigenic respiratory diphtheria at a correctional facility in Cape Town, South Africa. The first outbreak in October 2023 included 1 fatal case and 8 asymptomatic carriers testing positive for Corynebacterium diphtheriae. In December 2024, the second outbreak resulted in 1 case and 12 asymptomatic carriers. A third outbreak in February 2025, occurring 6 weeks after the second, resulted in 1 case and 14 asymptomatic carriers among inmates and staff. Contact tracing, antimicrobial prophylaxis, and vaccination campaigns were conducted with each outbreak. We outline public health responses to the 3 outbreaks and highlight key barriers and enablers for effective control in a highly mobile, densely populated correctional setting. Effective outbreak response in correctional facilities requires intersectoral collaboration and the development of adult vaccination guidelines for staff and inmates to prevent future vaccine-preventable disease outbreaks.

Murine typhus is a reemerging infectious disease with the potential for severe manifestations. We conducted a retrospective study to examine severe illness in those hospitalized with murine typhus in Galveston, Texas. We identified 149 cases, of which 119 (79.8%) were hospitalized and 33 (28%) required admission to the intensive care unit (ICU). ICU patients were older than non-ICU patients (54.9 vs. 47.2 years; p<0.02). Thrombocytopenia was more severe in the ICU group (101 × 10³ µ/L) compared to the non-ICU group (137 × 10³ µ/L) (p<0.01). The median time from healthcare contact in the emergency department to initiation of appropriate antibiotics was similar for the ICU group (1 day) and non-ICU group (2 days) (p = 0.26). Two deaths (1.7%) in the ICU group were attributed to multiorgan failure and hemophagocytic lymphohistiocytosis. In murine typhus–endemic regions, early recognition and prompt treatment is imperative to mitigate adverse outcomes.

Tuberculosis (TB) outbreaks in the United States can cause substantial illness. Using surveillance and genotyping data, we applied a plausible source–case algorithm to identify TB cases reported during 2018–2020 responsible for secondary cases attributed to recent Mycobacterium tuberculosis transmission during 2020–2022. We used mixed models and a machine learning workflow to assess sociodemographic, clinical, and social risk factors associated with plausible sources. In mixed models, sputum smear positivity, cavitary disease, race/ethnicity other than non-Hispanic White or non-Hispanic Asian, age <65 years, US birth, and homelessness were associated with plausible sources. An adaptive boosting model achieved an area under the receiver operating characteristic curve of 0.81 on test data. Transmission was heterogeneous; 8.1% of sources linked to 3–15 secondary cases accounted for 24.9% of transmission events. Focusing case management and contact investigations on cases with the characteristics we identified could reduce M. tuberculosis transmission and improve TB prevention.

We explored the association between frailty and respiratory infectious diseases (RIDs) through a large cohort of 423,691 participants in the UK Biobank. Participants without baseline RIDs were assessed by physical frailty and frailty index. A total of 16,848 participants had repeated assessments. We divided participants into nonfrail, prefrail, and frail groups and categorized frailty changes as alleviation, maintenance, or aggravation. We estimated risk for RIDs, including influenza, pneumonia, and other acute lower respiratory infections. Compared with nonfrailty, prefrailty and frailty increased risk for RIDs 1.32–2.29 times. Each 0.1-point increase in frailty index per year raised risk for RIDs by 47%; each 1-point increase in physical frailty per year increased risk by 26%. Frailty worsening (e.g., aggravation of prefrailty) amplified risk by 2.31–4.16 times. Partial frailty improvement did not fully eliminate risk. Frailty is a modifiable, dynamic risk factor, underscoring the need for early frailty identification and intervention to reduce RIDs in high-risk populations.

Antimicrobial-resistant Neisseria gonorrhoeae poses a serious public health threat. In Australia, N. gonorrhoeae isolates with ceftriaxone MICs >0.125 mg/L or azithromycin MICs >256 mg/L required follow-up by public health officials. Odds of culture-positive notifications meeting those criteria increased from 2017–2019 (n = 11) to 2022–2024 (n = 94) (odds ratio 8.58 [95% CI 4.81–17.0]). Local acquisition was frequent (78.7%). Isolates with decreased ceftriaxone susceptibility were more common in female and heterosexual patients than were isolates with high-level azithromycin resistance. We identified 9 genomically linked clusters (<15 single-nucleotide polymorphisms), 3 with sizable clonal expansion. Initial test of cure was negative for 81/94 (86.2%) 2022–2024 cases; of the rest, 9 cases had no follow-up visits, 2 were reinfected, and 2 failed initial treatment. Improving follow-up and reporting of treatment failure would strengthen case management protocols. Culture-based diagnostics remain essential to detect antimicrobial resistance, inform surveillance, and curb the rising resistance trend.

Community-acquired multidrug-resistant (MDR) Enterobacterales bacteria are an increasing public health concern, yet whether households play a role in community spread remains unclear. We investigated 150 households with children in St. Louis, Missouri, USA, for MDR Enterobacterales. We cultured swab specimens from household members and environmental surfaces for identification and antimicrobial susceptibility testing. We also performed whole-genome sequencing in the 53 (35%) households where >1 MDR Enterobacterales species were recovered. Enterobacter hormaechei predominated, followed by Klebsiella pneumoniae and Pantoea species. Whole-genome sequencing revealed closely related strains shared between persons and environmental surfaces, suggesting potential intra-household transmission. We identified >1 horizontal gene transfer event between Enterobacterales genera within a household. On multivariable analysis, households that had children attending daycare, a member with an ADHD diagnosis, and dog ownership were associated with increased odds of household MDR Enterobacterales colonization. Households likely serve as major contributors in acquisition and community spread of MDR Enterobacterales.

Feline sporotrichosis is a public health concern because it is a zoonotic illness and has a prolonged treatment time. We report laboratory-confirmed cases of feline Sporothrix schenckii complex infection submitted to a laboratory in Thailand during 2023–2025 and evaluate their in vitro antifungal drug susceptibility profiles for amphotericin B, itraconazole, posaconazole, voriconazole, ketoconazole, fluconazole, and flucytosine. A total of 1,178 S. schenckii complex isolates were identified. Overall, 368 isolates did not show reduced susceptibility. We observed single-drug reduced susceptibility to amphotericin B (60 isolates), posaconazole (41 isolates), voriconazole (9 isolates), and terbinafine (4 isolates). We observed a reduced susceptibility to itraconazole in 687 isolates: 321 single-drug, 270 co-reduced, and 96 multidrug-reduced isolates. An increasing number of feline sporotrichosis cases and escalating reduced susceptibility to itraconazole underscore the need for continued surveillance and susceptibility testing to support management in complex cases.

During August 2022–December 2023, a total of 110 bloodstream infections caused by Wickerhamomyces anomalus (synonym Candida pelliculosa) were identified across 8 hospitals in 3 cities in Venezuela. Most cases (82/110 in Caracas) occurred in a single pediatric intensive care unit, predominantly among neonates. Molecular genotyping indicated multiple events of clonal transmission, which was supported by epidemiologic clustering of patients. Antifungal susceptibility testing demonstrated good in vitro activity; most isolates were classified as wild-type. Our findings underscore the need for enhanced fungal diagnostics, infection prevention measures, and national surveillance to mitigate hospital-associated fungal transmission in resource-limited settings.

During March–July 2025, ten cases of Wickerhamomyces anomalus bloodstream infection were identified in Pereira, Colombia, mainly affecting pediatric patients; 9 cases occurred in children (8 neonates and a 5-year-old girl) and 1 case was in an adult. Most neonates were preterm and had multiple underlying conditions, such as congenital anomalies, respiratory complications, and adverse perinatal conditions, often compounded by limited prenatal care and maternal infections. All patients required intensive medical interventions, including central and peripheral venous catheters, mechanical ventilation, parenteral nutrition, and, in some cases, surgical procedures. Broad-spectrum antibacterial therapy was widely used, and antifungal treatment, primarily caspofungin, was initiated in half of cases. Antifungal susceptibility testing demonstrated low MICs for all agents. Short tandem repeat genotyping of 6 isolates indicated clonal transmission, supporting a healthcare-associated outbreak. Despite prolonged hospitalizations and severe clinical conditions, all patients survived, highlighting the importance of prompt diagnosis, strict infection control, and appropriate antifungal management.

During molecular surveillance of human adenoviruses (HAdVs) in children hospitalized with acute lower respiratory tract infections in Beijing, China, during 2014–2024, the most prevalent genotypes were HAdV-B114 (53.85%) and HAdV-B7 (27.18%). A novel recombinant genotype, HAdV-B117, was identified in 2 children <5 years of age with severe community-acquired pneumonia and serious complications. Genomic analysis revealed that HAdV-B117 arose from HAdV-B114 (P7H3F3) with the fiber gene from HAdV-B7. We observed amino acid substitutions and deletions in the pivotal regions of 3 major capsid proteins, and some were predicted to alter the protein structure. In vitro, the replication kinetics of HAdV-B117 were similar to those of HAdV-B3 and HAdV-B7. Clinical manifestations resembled severe pneumonia caused by HAdV-B3 or HAdV-B7. Both children recovered after treatment. The emergence of HAdV-B117 highlights the need for continuous genomic surveillance of HAdVs to detect novel recombinants with potential public health effects.

We report a genomically linked cluster of 9 Dermatophilus congolensis cutaneous infections diagnosed within 2 months among men who have sex with men in Lyon and Paris, France, 2025–2026. Genomic similarity and shared sexual exposures strongly suggest interhuman sexual transmission of this zoonotic bacterium.

Dermatophilosis is considered a zoonotic infection. We report 9 cases among men who have sex with men in Barcelona, Spain, during December 2025–March 2026. Whole-genome sequencing revealed highly related isolates forming a distinct lineage within the genus Dermatophilus. Epidemiologic and clinical features of the cases support human-to-human transmission via sexual contact.

Congenital lymphocytic choriomeningitis virus (LCMV) infection is associated with major neurologic malformations and fetal demise. We report 2 cases of probable congenital LCMV infection and chorioretinitis, cerebral ventriculomegaly, and placental histopathology in Philadelphia, Pennsylvania, USA. Clinicians who suspect congenital LCMV infection should screen for chorioretinitis, LCMV antibodies, and evidence of placental pathology.

We report zoonotic transmission of Eurasian avian-like swine influenza A(H1N1) virus from pigs to a farmer. The pigs and farmer experienced influenza-like illness. Whole-genome sequencing revealed >99.9% viral sequence identity between hosts. Our findings highlight the risk posed by enzootic swine influenza A virus and the need for genomic and epidemiologic surveillance.

Trichophyton indotineae is an emerging dermatophyte frequently associated with terbinafine resistance. We report a case of recalcitrant T. indotineae infection in Singapore with limited response despite prolonged azole therapy, which only resolved after combination therapy with anidulafungin and itraconazole. This case highlights therapeutic challenges and need for improved diagnostics in T. indotineae infections.

We report 5 gonorrhea cases caused by ceftriaxone-resistant penA–60-carrying Neisseria gonorrhoeae bacteria during January–April 2025 in Thailand, successfully cured by ceftriaxone therapy. Most patients had prior over-the-counter antimicrobial drug exposure. Ceftriaxone-resistant gonococcal strains are spreading in Thailand, and strengthened gonorrhea and resistance surveillance and effective antimicrobial stewardship programs are needed.

Genomic analyses identified 4 seventh pandemic Vibrio cholerae El Tor clades in Thailand (2007–2025). Closely related to other South Asian strains, the clades reveal that repeated cross-border introductions, rather than local persistence, drive outbreaks. Our findings highlight the importance of genomic surveillance for monitoring transmission and informing regional control strategies.

In 2023, a new yellow fever virus (YFV) lineage was introduced in São Paulo state, Brazil. During July 2024–June 2025, nine Callithrix penicillata marmosets tested YFV–positive, showing high viral loads and characteristic organ lesions. Those results highlight the need to include these animals in multispecies surveillance strategies for early YFV detection.

We describe infections and other adverse outcomes among US residents who traveled for cosmetic procedures within the United States or abroad during 2014–2024. Outbreaks of adverse events related to such procedures often involve multiple states and geographically separated patients, making outbreak detection and investigation challenging.

We analyzed inpatient data from Texas, USA, to characterize hospitalizations for disseminated coccidioidomycosis and coccidioidal meningitis from 2016–2023. Geographic mapping revealed a substantial disease effect in both western Texas and metropolitan areas. Our findings suggest the need for enhanced surveillance and increased healthcare provider awareness regarding coccidioidomycosis in Texas.

Caballeronia spp. are gram-negative bacteria belonging to the Burkholderiaceae family, commonly found in the environment and in association with plants and animals. However, the bacteria are an uncommon cause of human infection. We describe Caballeronia bacteremia in 2 children with cancer in Tennessee, USA.

We summarize an outbreak investigation of Neisseria gonorrhoeae sequence type 16676 associated with disseminated gonococcal infections in Minnesota, USA, in 2025. This strain emerged rapidly, carried a plasmid with a tetracycline resistance gene, and encoded a porB1a allele. Prospective genomic surveillance enabled detection and epidemiologic investigation of this outbreak.

We isolated Cutibacterium avidum bacteria from remanant siliconomas noted during left mastectomy with reconstruction and right breast reduction in a 48-year-old woman with prior history of silicon injections. Chronic siliconomas can support anaerobic colonization, posing infection risks relevant to reconstructive and oncologic timelines.

We report an increase of bla_NDM among carbapenemase-producing, carbapenem-resistant Enterobacterales collected in the United States through the Emerging Infections Program’s Multi-site Gram-negative Surveillance Initiative. Among 1,288 isolates identified, the percentage harboring bla_NDM increased from 5.4% in 2016 to 39.8% in 2023.

Primary prevention includes interventions that prevent the initial occurrence of disease; in the context of pandemic origins, one class of primary preventative interventions involves reducing the risk of zoonotic pathogen spillover. Pandemics are rare events, therefore data on spillover events of known pandemic pathogens are also rare. In contrast, many zoonotic viruses spill over frequently but fail to spread efficiently between humans. We consider whether insights from frequent spillovers of poorly-spreading viruses should be used to inform primary prevention strategies aimed at viruses that spill over rarely but spread well human-to-human. We propose a set of principles to steer future research and guide deployment of preventative strategies. We believe that a precautionary approach, grounded in evidence from viruses that spill over frequently, offers the most practical empirical foundation for guiding primary spillover prevention.

Anaplasmosis, an emerging tickborne zoonosis, infrequently involves the central nervous system, and cerebrospinal fluid (CSF) profiles of anaplasmosis remain poorly characterized. We conducted a multisite retrospective study of patients hospitalized with anaplasmosis during November 1, 2014–November 29, 2024, in Minnesota and Wisconsin, USA, a hyperendemic region. Included patients had anaplasmosis confirmed by PCR on blood samples, exhibited neurologic symptoms, and had lumbar puncture procedures. Ten hospitalized patients met inclusion criteria, 6 with meningitis, 3 with meningoencephalitis, and 1 with encephalitis. CSF findings were within reference ranges for 5 patients; 4 patients demonstrated mild lymphocytic pleocytosis, but glucose and protein levels were within reference ranges. One patient underwent a traumatic lumbar puncture resulting in neutrophilic pleocytosis. CSF abnormalities did not correlate with neurologic severity, suggesting a cytokine-mediated process rather than direct central nervous system infection. All patients rapidly improved with doxycycline, highlighting the need for early recognition and empiric therapy for anaplasmosis.

Diagnosis of coccidioidomycosis is challenging and requires a high index of clinical suspicion. We estimated the incidence and duration of, and risk factors associated with, diagnostic delays and missed opportunities in the diagnosis of coccidioidomycosis. We conducted a retrospective analysis of health insurance claims data in the United States during 2001–2022 included in the Merative MarketScan Databases. Using a case-crossover design and a bootstrapping approach, we estimated the number of excess visits for coccidioidomycosis-related symptoms before diagnosis. We also evaluated potential factors associated with delay. We estimated that almost 60% of patients experienced >1 missed opportunity for diagnosis; the average diagnostic delay was 29.69 (95% CI 28.25–31.18) days. Missed opportunities were predominantly observed in outpatient settings (73%) and were significantly associated with older age, rural residence, underlying pulmonary conditions, and prescriptions for antibiotics or inhalers. Diagnostic delays for coccidioidomycosis are common, and addressing such delays could improve clinical outcomes.

Snowshoe hare virus (SSHV) is an arbovirus in the California serogroup known to circulate throughout Canada and northern latitudes of the United States. The clinical spectrum of SSHV infection ranges from asymptomatic or mild febrile illness to neuroinvasive disease; neuroinvasive disease occurs more often in children and young adults. We describe a cluster of confirmed and probable SSHV meningoencephalitis cases in 3 children from Whistler, British Columbia, Canada, in the summer of 2024. We highlight the shared epidemiology, clinical manifestations, serologic diagnostic methods, and outcomes for the cases. All 3 children acquired the infection locally and made a full recovery. This case series suggests underrecognized SSHV infection prevalence that warrants enhanced surveillance and review of existing diagnostic algorithms. California serogroup viruses, including SSHV, should be recognized as a potential cause of neuroinvasive disease in North America during mosquito season, particularly when initial diagnostic testing is inconclusive.

Blastomyces urine antigen testing is a sensitive blastomycosis diagnostic method, but its utility for active case identification during outbreaks is unknown. We evaluated urine antigen testing for identifying blastomycosis cases during a 2023 outbreak at a Michigan, USA, paper mill and assessed demographic and clinical factors associated with test positivity. Approximately 2 months after the outbreak was recognized, we collected work and health information for 603 employees; 95% (n = 578) underwent urine antigen testing and 9% (n = 52) tested positive, including 25 previously undetected cases. Blastomycosis-like symptoms were associated with test positivity (p<0.001), but 10% of employees with positive results were asymptomatic. Recent hospitalization for blastomycosis was associated with test positivity (p = 0.02) and higher antigen levels. Further research into urine antigen testing is needed clarify its suitability for detecting mild and asymptomatic infections during outbreak investigations. Urine antigen testing had high acceptability among employees and effectively identified additional cases.

Reports of ocular manifestations of Lyme disease (LD) are uncommon, and signs and symptoms may be overlooked by physicians. We conducted a retrospective case series of ocular LD reported during 1988–2025. Among 27 published reports in PubMed, we noted that, in 38 cases, the most common ocular manifestation was uveitis, representing 45% of cases, followed by optic neuritis and cranial nerve palsies (including trochlear and abducens). Not all cases met Centers for Disease Control and Prevention surveillance guidelines for LD, given that some case reports were published before the current guidelines. Cases that provided microbiologic proof were 2 anterior uveitis cases, 1 case of anterior uveitis with abducens’s nerve palsy, 1 case of intermediate uveitis, and 1 case of intranuclear ophthalmoplegia. Ocular LD can have a broad variety of manifestations; therefore, physicians should be aware of those manifestations and obtain microbiologic proof for a more definitive diagnosis and epidemiologic value when possible.

Group A Streptococcus (GAS) causes a variety of diseases in humans but is not widely appreciated as a cause of meningitis. During 1997–2022, ten sites participating in the Active Bacterial Core Surveillance network in the United States identified GAS meningitis cases. We calculated annual incidence and case-fatality rates (CFRs) for 320 of those cases and determined antimicrobial resistance by whole-genome sequencing. Annual incidence of GAS meningitis ranged from 0.02 to 0.07 cases/100,000 persons. Children <1 year of age had the highest average annual incidence, 0.23 cases/100,000 children. GAS meningitis had a higher CFR (19.4%) than meningitis caused by group B Streptococcus, Streptococcus pneumoniae, Neisseria meningitidis, or Haemophilus influenzae. Clindamycin resistance among GAS meningitis isolates increased from 3.2% during 1997–2002 to 17.7% during 2018–2022. Clinicians should be aware that meningitis is an uncommon but severe manifestation of invasive GAS and has a higher CFR than more established meningitis etiologies.

A previous study demonstrated noninferior efficacy of 4-month rifapentine/moxifloxacin regimen for tuberculosis (TB) treatment compared with the standard regimen. We analyzed pregnancy outcomes of women who became pregnant during the study. Among 740 women, 97 (13.1%) became pregnant. Of 102 pregnancies (in 97 participants), 30 (29.4%) participants were exposed to study drugs. Fetal loss was reported for 3/13 (23.1%) in the control regimen, 1/9 (11.1%) in the rifapentine/moxifloxacin regimen, and 1/8 (12.5%) in the rifapentine regimen. Among 21 live births in exposed pregnancies (7 in each arm), 1 infant with a congenital anomaly was reported in a participant on the rifapentine regimen. Among women receiving a short rifapentine/moxifloxacin regimen for tuberculosis who became pregnant, we observed no elevated rates of fetal losses or congenital anomalies.

Haematospirillum jordaniae was first identified as a human pathogen in 2016. In this article, we describe 4 patients who had H. jordaniae infections identified in 2020 and who had temporally and spatially linked environmental exposures. Three of the 4 patients reported leg injuries while participating in recreational river water activities in south-central Pennsylvania, USA. In 2024, we detected H. jordaniae in river samples collected at locations identified during patient interviews. All patients sought emergency department services for clinical assessment; however, the causative bacterial isolate was not initially identified. H. jordaniae was identified as the bacterial cause months after patient treatment and discharge. Although H. jordaniae infections are considered rare, the true occurrence is unknown. Additional information about the organism’s ecology and environmental seasonality could guide public health messaging and increase awareness among healthcare providers.

Reptile-associated outbreaks of human Salmonella infections are increasing in Canada, coinciding with a rise in the popularity of reptiles as pets. We conducted a retrospective analysis of surveillance data for human Salmonella case-patients in Ontario during 2015–2022. We compared serotypes and reptile types for those reporting domestic reptile or amphibian exposure with veterinary Salmonella isolates reported during the same period. Case-patients commonly reported contact with reptile types from which Salmonella was most frequently isolated. Some serotypes from human case-patients were closely associated with contact with specific reptile types, including Salmonella Paratyphi B biovar Java (Salmonella Paratyphi B variant L (+) tartrate +) with snakes, Salmonella Agbeni with turtles, and Salmonella Cotham, Salmonella Chester, and Salmonella Tennessee with bearded dragons. Salmonella was most likely to be reported from reptiles fed a carnivorous diet. Education of reptile owners could help promote proper veterinary care and reduce transmission of zoonotic infections.

Candida bloodstream infections, and their increasing antifungal resistance, are a global concern. In this cross-sectional study, we analyzed 2,443 culture-confirmed candidemia cases reported in South Africa during 2012–2017 to assess the effect of previous antifungal exposure on nonsusceptible Candida infection. We classified cases by species resistance profile and patient’s antifungal use within 14 days before infection. We found that 48% of cases were caused by nonsusceptible species, and 20% of patients had prior antifungal exposure, mainly to fluconazole. In patients >90 days of age, prior antifungal use was significantly associated with nonsusceptible Candida bloodstream infection (adjusted OR 2.02, 95% CI 1.43–2.87; p<0.001), with species-specific effects. No such association was found in neonates and young infants, for whom hospital transmission appeared more influential. Our findings underscore the need for targeted antifungal stewardship and enhanced infection prevention to mitigate antifungal resistance in South Africa.

The complexity of rickettsial serodiagnostics during acute illness has limited clinical characterization in Africa. We used archived samples from sepsis (n = 259) and acute febrile illness (n = 70) cohorts in Uganda to identify spotted fever and typhus group rickettsiae by using immunofluorescence assay and clinically validated rRNA reverse transcription PCR (RT-PCR). Among 329 participants, 10.0% had rickettsial infections (n = 33; n = 20 identified with immunofluorescence assay and n = 13 by RT-PCR). Serum rRNA RT-PCR was 75.0% (95% CI 42.8–94.5%) sensitive and 91.2% (95% CI 85.8–95.1%) specific. Thrombocytopenia was more common among patients with rickettsial infections than with other nonmalarial infections (adjusted odds ratio 3.7; p = 0.003). No participants were on a tetracycline antimicrobial drug at admission. rRNA RT-PCR is a promising diagnostic strategy for identifying acute rickettsial infections. Doxycycline should be included in empiric antimicrobial drug regimens for nonmalarial febrile illness in this region.

Prevalence of emerging fungal infections is increasing, particularly among immunocompromised persons, children, and older persons. We report 108 cases of Scheffersomyces spartinae infection in pediatric patients from Karachi and other cities in Pakistan, of which 107 were identified from blood cultures. Cultures were initially misidentified as Clavispora lusitaniae by a biochemical assay before speciation as S. spartinae by whole-genome sequencing. All isolates were from children <12 years of age, and >69% were from children <1 month of age. Isolates were genetically distinct across regions of Pakistan; however, genetic diversity was low in isolates from patients in Karachi and nearby Nawabshah and had median differences of just 9 pairwise nucleotide variants. This study demonstrates S. spartinae is a potentially emerging pathogen in neonates and young infants in Pakistan. The findings highlight the limitations of phenotypic identification for detecting emerging fungal infections and underscore the value of molecular identification approaches.

Mpox was first identified against the backdrop of the smallpox eradication campaign. Monkeypox virus (MPXV), the causative agent of mpox, has been maintained in animal reservoirs in the forested regions of West and Central Africa as 2 distinct clades; clade I has historically caused more severe infection in Central Africa than clade II, historically found in West Africa. However, rapid reemergence and spread of both MPXV clades through novel routes of transmission have challenged the known characteristics of mpox. We summarize mpox demographic distribution, clinical severity, and case-fatality rates attributed to genetically distinct MPXV subclades and focus on MPXV clade Ib, the more recently identified subclade. Broad worldwide assistance will be necessary to halt the spread of both MPXV clades within mpox endemic and nonendemic regions to prevent future outbreaks.

Talaromycosis is a life-threatening fungal disease that primarily affects immunocompromised persons in Southeast Asia. We conducted a multicenter, case–control study recruiting participants with advanced HIV disease in Vietnam; 205 case-patients with culture-confirmed talaromycosis were matched to 405 control-patients by age, sex, and CD4 count. Occupational exposure to tropical plants (odds ratio [OR] 1.73 [95% CI 1.10–2.73]; p = 0.017) and to farmed animals (OR 2.07 [95% CI 1.20–3.55]; p = 0.009) were independent risk factors for talaromycosis. Talaromycosis risk was higher in participants from highland regions than in persons from lowland regions (p<0.05). Participants from lowland regions who had lived or traveled to highland regions had a higher risk for talaromycosis (OR 3.15 [95% CI 1.49–6.64]; p = 0.003). This study confirms the epidemiologic correlation between talaromycosis and soil exposure and demonstrates an epidemiologic link between talaromycosis and residence in or travel to highland regions of Vietnam.