Articles from Emerging Infectious Diseases

Highly pathogenic avian influenza H5Nx viruses remain a major zoonotic threat, yet global attention has focused largely on clade 2.3.4.4b, potentially overlooking major changes within long-endemic H5N1 lineages in Asia. Recent reports from South and Southeast Asia describe the emergence of reassortant clade 2.3.2.1 viruses alongside renewed human infections after apparent prolonged epidemiologic stability. Collectively, those events suggest a regional pattern rather than isolated anomalies. In this article, we argue that reassortment, rather than point mutation alone, might be an underrecognized driver of zoonotic risk in endemic H5N1 lineages and is reshaping those lineages. We examine why such events might be underrecognized in settings with entrenched poultry influenza, identify limitations of current surveillance systems, and call for integrated, real-time approaches linking genomic detection with phenotypic assessment across animal and human health sectors to enable timely risk assessment and coordinated public health action.

Bundibugyo virus disease (BVD), an Ebola virus species with no licensed vaccine or therapeutic, reemerged in May 2026 as a cross-border outbreak in Uganda and the Democratic Republic of the Congo. During a 2-day workshop, July 8–9, 2026, we conducted an early action review of the outbreak response using the 7-1-7 framework (7 days to detect, 1 day to notify, 7 days to complete early response actions) to assess timeliness and identify bottlenecks and enablers across 9 response pillars. Uganda declared its outbreak on May 15, 2026; by July 8, the country had recorded 20 confirmed cases (15 imported, 5 locally transmitted) and a case-fatality rate of 15%. Uganda met all 3 targets: detection in 6 days, notification in <1 day, and response completion in 2 days. Low clinical suspicion, cross-border data-sharing gaps, fragmented digital systems, and delayed community engagement were common bottlenecks; strong leadership and coordination structures were most cited enablers.

Crimean-Congo hemorrhagic fever (CCHF) during pregnancy is associated with severe maternal and fetal complications, but evidence remains limited to heterogeneous case reports. We synthesized patient-level data from published and unpublished cases identified through systematic database searches and direct collaboration with centers in CCHF-endemic areas. We harmonized patient-level clinical, laboratory, obstetric, treatment, and outcome data for 55 pregnancies. The maternal mortality rate was 28.8% (15/52), and fetal loss occurred in 57.4% (31/54) of cases. Maternal mortality rates increased with advancing gestation, reaching 31.3% in the third trimester, but fetal loss was highest (85.7%) in the first trimester. Ribavirin treatment during the third trimester was associated with lower observed maternal mortality rates (odds ratio 0.33, 95% CI 0.13–0.84; p = 0.031). Our findings highlight gestational age–specific risks of CCHF and support the need for standardized management protocols and strengthened CCHF surveillance during pregnancy in endemic regions.

Anaplasma capra is a recently discovered bacterial tickborne pathogen that was first identified in goats in 2012 and later in humans in China in 2015. We detected and genetically characterized A. capra in adult patients with suspected Crimean-Congo hemorrhagic fever (CCHF) in Turkey during the 2022 outbreak. We screened all patients for A. capra by using nested PCR targeting the gltA and groEL genes. We confirmed CCHF by molecular and serological tests. Of 263 patients, 6 (2.28%) were positive for A. capra. Sequence analysis revealed 84.16%–100% gltA gene similarity and 90.24%–100% groEL gene similarity with GenBank entries. Phylogenetic analysis confirmed all A. capra gene sequences belonged to genotype 1. Our results demonstrate clinical evidence of genotype 1 A. capra infection in humans. Our findings highlight the need for clinicians to consider A. capra in the differential diagnosis of CCHF-like symptoms, especially in endemic areas.

We conducted a systematic review and meta-analysis of group B Streptococcus (GBS) rectovaginal colonization prevalence, serotype distribution, and antimicrobial drug resistance (AMR) rates among pregnant women in the Asia-Pacific region. We included articles published in the MEDLINE, Embase, and PubMed databases during January 2014–October 2025. Overall, 1,623 studies were identified; 98 of those were included in the meta-analysis. Of 978,150 pregnant women, 172,973 were colonized with GBS; pooled estimated prevalence was 18.0% (95% CI 12%–23%). Studies from Southeast Asia were limited. GBS serotype distributions were reported in 24 studies; serotype III was the most common (range 5.0%–100.0%). Thirty studies included AMR rates; low (0%–2.0%) AMR rates were found for β-lactams. GBS colonization is common among pregnant women in the Asia-Pacific region. Continued surveillance of GBS prevalence will be needed, particularly in Pacific and Southeast Asian countries, to guide effective GBS prevention and treatment programs.

After its elimination from Mexico in 2003, myiasis caused by New World screwworm (NWS), Cochliomyia hominivorax, has recently reemerged as a public and animal health concern. We conducted a retrospective study of human New World screwworm myiasis cases reported through Mexico’s national surveillance system during April 13, 2025–March 14, 2026. Of 204 cases in official surveillance summaries, 202 had sufficient information for case-level clinical and epidemiologic analysis. Cases were concentrated in southern Mexico, particularly Chiapas, followed by Yucatán, Oaxaca, and Quintana Roo. Most (71.8%) cases occurred in men; mean patient age was 61.1 years. Lower limbs (55.0%) were the most frequently reported anatomic location, and 76.7% of patients had >1 concurrent condition. Six deaths were reported among patients with NWS myiasis; at the time of reporting, 1 death was attributed directly to NWS myiasis. Our findings support proactive clinical detection and integrated One Health surveillance along the expected northward spread of NWS.

In this meta-analysis, we performed a literature search for articles relating to asymptomatic monkeypox virus (MPXV) detections published worldwide during May 12, 2022–September 13, 2024. The primary outcome was to determine the pooled prevalence of asymptomatic MPXV detections. We conducted a random-effects analysis that yielded a final pooled prevalence of 1.0% (95% prediction interval 0.1%–11.2%). Results did not substantially differ by geographic region or study design. Although those findings are reassuring, we did not evaluate infectivity or transmission potential among asymptomatic persons. MPXV continues to circulate globally; the viral dynamics that enable its persistence remain poorly understood and merit further study.

Salmonella enterica subspecies enterica serovar Infantis carrying the bla_CTX-M-65 gene has been increasingly detected globally, including in South Korea, since 2022. We analyzed 65 bla_CTX-M-65–positive Salmonella Infantis isolates from humans, poultry, and wastewater collected during 2022–2024 by using whole-genome sequencing and phylogenomic analysis. All isolates were multidrug resistant, commonly to aminoglycosides, β-lactams, quinolones, tetracyclines, amphenicols, and folate pathway inhibitors. Phylogenetic analysis revealed high genetic similarity among isolates from humans, poultry, and wastewater, which were intermingled within monophyletic clades with high bootstrap support, indicating close genomic relatedness across sectors. Bayesian phylogeographic reconstruction suggested multiple potential introductions during 2018–2022, including 1 lineage related to isolates from the United States (clade I) and others related to isolates from the United Kingdom (clade II). Those findings highlight the emergence and genomic diversity of bla_CTX-M-65–positive Salmonella Infantis in South Korea and support the value of continued genomic surveillance across sectors.

Swine influenza A viruses (IAV-S) caused the 2009 H1N1 pandemic and pose a future zoonotic and pandemic threat. Vietnam represents a critical hotspot for IAV-S emergence within East and Southeast Asia, with dense swine and human populations and intensive livestock trade. We conducted genomic surveillance of IAV-S in Vietnam during 2020–2024, extending previous surveillance from 2013–2019. We identified multiple co-circulating H1 and H3 clades, including pandemic H1N1, Eurasian avian-like, and European lineages, by conducting phylogenetic analysis of 56 IAV-S isolates (21 H1N1, 31 H1N2, and 4 H3N2). Three H1 clades persisted exclusively in Vietnam, circulating up to 12 years. Phylogeographic analysis revealed multiple independent introduction events from North America, Europe, China, Thailand, and Cambodia. We detected extensive reassortment that frequently involved pandemic H1N1 virus internal genes. We identified several lineage-specific mutations associated with mammalian adaptation. Our findings underscore the ongoing IAV-S evolution and need for sustained surveillance in Vietnam.

Nontyphoidal Salmonella enterica serovar Hadar causes poultry-associated salmonellosis outbreaks in the United States. One persisting strain of Salmonella Hadar caused 5 multistate outbreaks resulting in ≈2,000 human cases during 2020–2023. The Centers for Disease Control and Prevention designated the strain as reoccurring, emerging, or persisting (REP), related within 26 core-genome allele differences. That REP strain has caused human illnesses by consumption of commercial poultry food products or contact with backyard poultry. To investigate the REP strain’s evolution and identify possible markers for source attribution, we performed phylogenetics and molecular clock analysis on 404 genomes subsampled from routine surveillance and outbreaks. The most recent common ancestor likely emerged in early 2018. We identified 2 clades: clade 1, associated with backyard poultry and other food sources, and clade 2, predominantly linked to commercial poultry products. We found 2 clade-specific single-nucleotide polymorphism markers; in silico screening of additional isolates supported their use for source attribution.

Bartonella quintana, the causative agent of trench fever, is a louseborne bacterial pathogen. During 2016−2017, we investigated B. quintana infection in macaques housed at 2 primate research institutes in Japan. We isolated B. quintana from 3 wild-caught Japanese macaques, which had been introduced into 1 institute in 2009. The macaques had received periodic ivermectin treatment every 1–2 years to control blood-feeding arthropods. Whole-genome comparisons revealed that the 3 isolates exhibit higher homology to a Japanese macaque–derived strain than to rhesus macaque–derived or human-derived strains. In addition, in all 3 isolates, the bepA locus was absent; we classified the trwL locus as structural variant C, consistent with known Japanese macaque–derived strains. Our findings suggest that B. quintana bacteremia in the macaques might have persisted for 7–8 years in captivity, and that the bacterium was not accidentally transmitted to them from humans by reverse zoonosis.

The Orthomyxoviridae family includes influenza D virus (IDV), an emerging pathogen primarily affecting cattle and swine; there is evidence of cross-species transmission and potential zoonotic risk. Although active human infections have yet to be confirmed, high seroprevalence in cattle-exposed populations highlights the need for continued surveillance. We developed and validated a rapid, field-deployable reverse transcription loop-mediated isothermal amplification assay for IDV detection; specificity was 99.2% and sensitivity ranged from 95.6% (cycle quantification <30) to 81.8% (cycle quantification <40). This method offers a cost-effective, accessible alternative to quantitative reverse transcription PCR, enabling improved monitoring of IDV and reinforcing preparedness for emerging influenza threats.

Campylobacter spp. remain the leading bacterial cause of foodborne gastroenteritis in Western countries. We report sustained, previously unrecognized circulation of a multidrug-resistant Campylobacter coli sequence type 10042 lineage across Europe during 2018–2025. Whole-genome sequencing of 217 isolates from 9 countries spanning human, animal, food, and environmental sources identified cross-border clusters, including a large lineage linking primarily Portugal and Luxembourg, as well as Germany, Ireland, Spain, and the United Kingdom. Genomic data indicates ongoing clonal expansion with increasing diversification over time. Isolates exhibited a conserved multidrug-resistant phenotype, including resistance to fluoroquinolones, tetracyclines, and β-lactams; reduced susceptibility to carbapenems was observed. Resistance was associated with GyrA Thr86Ile, tet(O/32/O)/tet(O) genes, and bla_OXA-61 promoter variants; variation in porA was linked to variable amoxicillin/clavulanic acid and ertapenem susceptibility. Those findings demonstrate that C. coli infections can involve sustained international transmission rather than sporadic cases and highlight the need for coordinated, cross-sector genomic surveillance to detect emerging antimicrobial-resistant lineages.

Highly pathogenic avian influenza (HPAI) A(H5N1) clade 2.3.4.4b virus continues to spread globally and sporadically transmits from avian reservoirs to mammalian hosts. In May 2024, H5N1 infections in young goats and alpacas in the United States were reported. Nevertheless, the overall susceptibility of camelids to clade 2.3.4.4b virus remains unclear. We conducted a controlled experimental infection study in 6 alpacas, assessing clinical signs, viral shedding, tissue distribution, and serologic responses after intranasal inoculation with HPAI H5N1 genotype B3.13 virus. Observed illness was generally mild; body temperature increased slightly and food intake reduced for up to 3 days postinfection. We detected viral RNA in nasal swab samples and confirmed infectious HPAI H5N1 virus. Immunohistochemistry and RNA in situ hybridization detected virus only in the nasopharyngeal tonsil and nasal conchae at 4 days postinfection. Our findings suggest alpacas are susceptible to productive H5N1 infection, highlighting implications for livestock surveillance and biosecurity in regions with ongoing circulation.

The province of Ontario, Canada, experienced a major resurgent outbreak of measles in 2025. We conducted wastewater surveillance concurrently with clinical-based surveillance to track measles incidence in southwestern Ontario, adjacent to the United States. Measles virus (MeV) signal in wastewater was positively associated with clinical cases but did not provide early alert of changes in measles incidence when resolved by epidemiologic week. Assessment of virus partitioning showed MeV RNA was broadly distributed in the liquid phase but is most concentrated in the solids. We adapted an assay for differentiation of vaccine and wild-type MeV and used it to detect vaccine genotype measles after a vaccination campaign targeting underserved groups. We estimated MeV shedding in wastewater through sampling of sewer laterals serving a hospital treating measles infections. This outbreak is a case study in which we highlighted the use of wastewater surveillance for measles while supporting method development in real time.

Variolation in China has a long history, yet the method remains underrepresented internationally, having limited recognition of medical rationale and indigenous development. We reviewed medical texts and records from late Imperial China and compared variolation chronology, techniques, and explanatory frameworks used in China versus India. Variolation in China was already in practice no later than the Chenghua–Longqing period of the Ming dynasty (1465–1572 CE), earlier than that reported in other countries. Sources from China described garment/blanket, lymph, and scab-derived inoculum methods for smallpox prevention. Scab-derived inocula, intranasal administration, and repeated passage techniques reflected empirical efforts to improve variolation reliability and reduce risk. Concepts of fetal toxin and seasonal pathogenic qi made variolation intelligible within contemporaneous medicine in China. Records from China predated sources from India and contained more detailed descriptions of variolation practices, supporting indigenous development and highlighting China’s central place in the early history of prophylactic inoculation.

Rabies was diagnosed in Cape fur seals by using direct fluorescent antibody testing in South Africa, 2024. We investigated the origin of rabies virus in this species. Phylogenetic analysis revealed virus introduction from jackals into seals, followed by sustained viral transmission within the seal population and spillover into a domestic dog.

A previously healthy 26-year-old man died of hemorrhagic fever with fulminant hepatitis and shock 36 hours after returning to France from Mecca, Saudi Arabia. Postmortem analyses detected low-level dengue virus RNA and positive NS1 antigen along with unexpected extremely high-titer disseminated velogenic avian orthoavulavirus 1 infection with elevated systemic cytokine responses.

By using historical contact tracing data, we estimated that 23.4% of case-patients caused 80% of Andes virus (ANDV) person-to-person transmission. We demonstrated a low but nonnegligible probability of observing a large-scale ANDV infection outbreak in a rodent-free setting consisting of close contacts, despite the historically self-limited person-to-person transmission of ANDV.

During the 2025 mpox outbreak in Sierra Leone, we assessed environmental contamination in 2 hospitals. Of 89 surfaces sampled, 6 (6.7%) surface samples, primarily from doors, were PCR-positive for monkeypox virus. Our findings highlight monkeypox virus surface contamination in healthcare settings and help prioritize infection prevention and control targets in resource-limited settings.

We report the emergence of macrolide-resistant Bordetella pertussis during a pertussis outbreak in Peru. Among 68 cases, 31% carried the A2047G gene mutation, conferring resistance to macrolides. Whole-genome sequencing revealed 2 genetically distinct groups, indicating multiple introductions into Peru. Our findings support strengthening surveillance for macrolide-resistant pertussis to inform control strategies.

In 2025, we detected highly pathogenic avian influenza H5N1 virus in dead waterfowl at Ibirapuera Park, São Paulo, Brazil. Genomic characterization indicated a reassortant virus that emerged from locally circulating low pathogenicity avian influenza viruses and highly pathogenic North American lineages. Our results highlight cross-species transmission risk and underscore the need for enhanced surveillance.

Tashkent, Uzbekistan, registered 290 invasive meningococcal disease cases during January–April 2026; the case fatality rate was 8.3%. Meningeal signs appeared in only 3.1% of patients and were the sole signs associated with death. Neisseria meningitidis serogroup surveillance and conjugate vaccine introduction will be needed to prevent invasive meningococcal disease in Uzbekistan.

We sequenced measles-positive samples from the 2025 outbreak in Texas, USA, and identified the expansion of a closely related genotype D8 lineage within broader strain diversity from North America. F:H419R was used as a lineage-associated genomic surveillance marker. Our findings demonstrate that whole-genome sequencing can strengthen measles surveillance and enhance outbreak investigations.

In 2025, highly pathogenic avian influenza A(H5N1) virus was detected in a poultry flock in Illinois, USA. Quantitative reverse transcription PCR, sequencing, and histopathology on cat and rat samples from the farm showed multiple positive tissues and high sequence identity to an avian isolate. Small mammals might contribute to H5N1 transmission.

We report a confirmed case of Chlamydia psittaci meningitis in Latin America, diagnosed in a 50-year-old farm worker from Chile. Diagnosis was established via cerebrospinal fluid quantitative real-time PCR and serology. The patient recovered after antimicrobial treatment. This case highlights the need to consider zoonotic pathogens in atypical meningitis.

Highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus continues to cause animal outbreaks and sporadic zoonotic infections. In a mouse model of lethal influenza disease, we compared oseltamivir, baloxavir, and molnupiravir monotherapies with 2-drug combinations. Baloxavir-based combinations improved survival, reduced lung viral loads, and prevented extrapulmonary dissemination, supporting H5N1 preparedness strategies.

Since 2021, a genotype 2.3.1, ciprofloxacin-resistant, multidrug-resistant (MDR) Salmonella enterica serovar Typhi strain increasingly has been detected in persons returning from West Africa. This strain locally acquired 2 different MDR plasmids over a ≈25-year period, underwent chromosomal integration of the IncHI1 plasmid MDR region, and finally acquired a gyrA mutation.

A large malaria outbreak caused by Plasmodium malariae parasites occurred in Khanh Hoa Province, Vietnam, in 2023. Since then, P. malariae parasites have persisted in the region alongside P. falciparum and P. vivax species, changing malaria patterns. Those findings reinforce the need for strengthened surveillance in the region.

We identified highly pathogenic avian influenza virus subtype H5 in stranded dolphins along the coastline of Brazil during 2023–2025. Infected animals included species classified as vulnerable or endangered. Our results highlight the need for ongoing surveillance of cetaceans susceptible to viral infections, which pose an additional threat to threatened species.

Trichodysplasia spinulosa polyomavirus (TSPyV) has been identified in human endothelial cell tumors. We evaluated 25 clinical cases of various inflammatory dermatoses in California, USA, for TSPyV by using RNAscope in situ hybridization. We did not detect TSPyV in any of the biopsy samples, suggesting that endothelial TSPyV is uncommon in inflammatory dermatoses.

Japanese encephalitis virus genotype V (JEV GV) has caused multiple cases of viral encephalitis in South Korea. We report a human case of JEV GV in China, confirmed by serology, sequencing, and quantitative reverse transcription PCR. We confirm JEV GV infection in China, highlighting the persistent threat of this virus.

Human papillomavirus types 6 and 11 are associated with mucosal condylomata acuminata, with rare reports of extragenital manifestations. We report a case of condyloma localized to the neck of an immunocompetent heterosexual man, without concurrent anogenital lesions. Our findings challenge theories of the site-specific tropism of these human papillomavirus types.

In July 2024, we reported information on the initial human mpox cases in Uganda. Genomic characterization of clinically suspected cases (July–December 2024) revealed cocirculation of several monkeypox virus clade 1b clusters and varicella zoster virus. Our findings highlight the need to refine differential diagnoses by molecular techniques and strengthen surveillance.

We compared data from the 2015 and 2024 pertussis epidemics in New South Wales, Australia. In 2024, we found twice as many notifications and a shift in distribution to older children. COVID-19 interventions and lack of circulation of pertussis likely contributed to an age cohort immunity gap and increased infections.

Because the epidemiology of Bundibugyo virus remains unclear, we reanalyzed the first recognized outbreak (Uganda, 2007). Adjusting for case under-ascertainment and the effect of control measures, we estimated the effective reproduction number (1.55, falling to <1 after intervention) and case-fatality rate (31%, declining to 25%). The underascertainment rate was 15%.

We report a cutaneous ulcer outbreak in Sierra Leone in 2025 that predominantly affected ≈403 schoolchildren. The causative agent was confirmed as Haemophilus ducreyi, a bacterium traditionally associated with the sexually transmitted infection chancroid but more recently recognized as an emerging cause of lower limb cutaneous ulcers in tropical regions.

Crimean-Congo hemorrhagic fever (CCHF) during pregnancy is associated with severe maternal and fetal complications, but evidence remains limited to heterogeneous case reports. We synthesized patient-level data from published and unpublished cases identified through systematic database searches and direct collaboration with centers in CCHF-endemic areas. We harmonized patient-level clinical, laboratory, obstetric, treatment, and outcome data for 55 pregnancies. The maternal mortality rate was 28.8% (15/52), and fetal loss occurred in 57.4% (31/54) of cases. Maternal mortality rates increased with advancing gestation, reaching 31.3% in the third trimester, but fetal loss was highest (85.7%) in the first trimester. Ribavirin treatment during the third trimester was associated with lower observed maternal mortality rates (odds ratio 0.33, 95% CI 0.13–0.84; p = 0.031). Our findings highlight gestational age–specific risks of CCHF and support the need for standardized management protocols and strengthened CCHF surveillance during pregnancy in endemic regions.

Western equine encephalitis virus (WEEV) reemerged in Argentina during 2023–2024, raising public health concerns and posing a potential threat to blood transfusion safety. We assessed the effect of WEEV circulation on the blood supply by implementing responsive, community-informed interventions within a regional hemovigilance system, including epidemiologic mapping, enhanced donor selection criteria, and alphavirus-specific nucleic acid testing. Among 637 donors residing in outbreak-affected areas, we detected 1 asymptomatic viremic donor. Phylogenetic analysis showed that the viral sequence clustered within the contemporary South American outbreak lineage, consistent with ongoing regional transmission. Those findings demonstrate silent WEEV circulation among blood donors and highlight the critical role of donor surveillance as a sentinel system for emerging arboviruses. Hemovigilance provides valuable insights into viral circulation in the broader population, underscoring the need to integrate molecular surveillance into routine blood bank practices to strengthen transfusion safety and public health preparedness.

Trichinella spp. nematodes are parasites that can cause trichinellosis in humans after consumption of infected, undercooked meat. A November 2024 trichinellosis outbreak in western North Carolina, USA, resulted in 3 cases (2 probable, 1 confirmed), all linked to undercooked bear jerky. In total, 6 persons consumed the implicated meat (attack rate 50%). Molecular testing identified Trichinella spiralis in leftover meat from the same bear. This outbreak provides evidence of changing trichinellosis patterns. Low-cost safety measures and prevention efforts regarding safe wild game preparation are needed to avoid future outbreaks.

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.