Early Release

Synopses

• Pediatric Meningoencephalitis Cluster Caused by Snowshoe Hare Virus, Whistler, British Columbia, Canada, 2024
  F. Ali et al.
• Circulation Patterns, Genetic Diversity, and Public Health Implications of Enterovirus D68, Europe, 2014–2024
  C. Andrés et al. View Abstract

  Enterovirus D68 (EV-D68) represents a continuing public health concern, given its association with severe respiratory illness and neurologic complications. In this study, we analyzed EV-D68 circulation and genetic evolution during 2014–2024 using data from 18 countries in Europe. Of 61,297 enterovirus-positive specimens, molecular detection and viral protein 1 sequencing identified 3,541 (6%) EV-D68 cases. A biennial circulation pattern was observed; detection rates ranged from 9% in 2014 to 0.9% in 2019. The pattern was disrupted in 2020 because of measures implemented in response to the COVID-19 pandemic, but then notable increases occurred in 2021 (14%), 2022 (10.7%), and 2024 (20.6%). Subgenogroups B3 (59.8%) and A2/D (28.0%) were predominant; A2/D reemerged as dominant in 2024. Mutation analyses revealed changes in antigenic regions. Our findings underscore the persistent adaptation and resurgence of EV-D68 after COVID-19. Continued genomic surveillance is essential to monitor transmission patterns caused by antigenic changes.

• Ecologic Investigative Strategies to Determine Human Plague Exposure Sites, United States, 1991–2018
  R. J. Eisen et al. View Abstract

  Plague is a rare but potentially life-threatening fleaborne zoonotic disease caused by Yersinia pestis. Public health agencies in the United States use multiple concurrent epidemiologic and ecologic strategies to determine Y. pestis exposure sites. We reviewed 196 plague case files from 1991–2018 to describe effort and yield of implemented strategies. All files included an epidemiologic component, and 71% were followed up with environmental investigations. Environmental samples were collected for laboratory testing in 88% of investigations. The percentages of investigations yielding laboratory evidence of local transmission varied from 28% for testing live-trapped rodents to 50% for pet serology. We suggest that collection and laboratory testing of samples should be prioritized when epidemiologic investigations implicate potential exposure in an unusual setting, in areas where many people could be at risk of exposure to Y. pestis, or in situations where prevention activities extend beyond educational outreach and incur greater costs.

Research

• Enhanced Detection of Coccidioides spp. Fungi from Environmental Samples Using Droplet Digital PCR
  J. Segovia-Mota et al. View Abstract

  Coccidioidomycosis (Valley fever), caused by Coccidioides spp. fungi, is a reemerging, neglected fungal disease endemic to arid and semiarid regions of the Americas. Environmental detection remains challenging because of spatial heterogeneity, seasonal variability, low DNA abundance, PCR inhibitors, and lack of standardized methods. We conducted environmental surveillance in Baja California, Mexico, an understudied region near the US–Mexico border, by collecting 74 soil samples from active rodent burrows across 5 locations. We evaluated droplet digital PCR (ddPCR) for Coccidioides detection and compared ddPCR with nested PCR targeting the internal transcribed spacer 1 region. ddPCR demonstrated greater sensitivity, detecting Coccidioides spp. DNA at all sampling sites, whereas nested PCR detected Coccidioides spp. DNA from only 1 site. Although additional work is required to rigorously quantify sensitivity and specificity, ddPCR could help identify Coccidioides environmental hotspots, thus enabling public health interventions, such as warning communities of areas that pose higher risk for infection.

• Hemolytic Uremic Syndrome Outbreak in Adults and Shiga Toxin–Producing Escherichia coli Negative for Locus of Enterocyte Effacement, France, 2025
  J. de Larminat et al.
• Dengue Incidence, Seroprevalence, and Expansion Factors from Active Surveillance, Brazil, 2016–2021
  E. de Barros et al. View Abstract

  Dengue is hyperendemic in Brazil and is underestimated by passive surveillance. To better understand dengue incidence, we conducted epidemiologic analyses among participants, 2–59 years of age, from the placebo arm of a phase 3 dengue vaccine trial. During 2016–2021, a total of 5,947 participants contributed to 22,028 person-years of follow-up. We identified and virologically confirmed dengue (VCD), Zika, and chikungunya infections. We observed VCD and chikungunya incidence heterogeneity by age, geographic location, and study year. Children 2–6 years of age experienced the highest VCD (2.33/100 person-years) and chikungunya (1.02/100 person-years) incidence. VCD peaked in 2019 (n = 148) whereas chikungunya peaked in 2017 (n = 51). VCD incidence rates from active surveillance were generally higher than those reported to the national passive surveillance system; expansion factor range was <1–9.5 by municipality. Active surveillance is critical to better understand and characterize dengue epidemiology.

• Confirming ERVEBO Vaccination to Support Ebola Virus Surveillance
  E. Karaaslan et al. View Abstract

  Accurate confirmation of Ebola vaccination (ERVEBO) is essential for interpreting serologic data and assessing vaccine coverage during Ebola virus (EBOV) outbreaks. Current GP1,2-based assays cannot reliably distinguish vaccine-induced immunity from responses generated by natural infection. We developed a multiplex Luminex assay incorporating EBOV GP1,2, secreted glycoprotein (sGP), and a modified vesicular stomatitis virus nucleoprotein (VSV-P-N), a vector antigen encoded by ERVEBO but absent from wild-type EBOV. By using samples from US vaccinees and controls and a small comparison set from the Democratic Republic of the Congo, we found sGP and VSV-P-N demonstrated 100% sensitivity and >97.6% specificity for identifying vaccinees. In samples collected after a ring vaccination campaign in Guinea, combined sGP and VSV-P-N positivity confirmed vaccination in 94.8% of persons with written and 90.8% of persons with verbal confirmation of vaccination history. Our findings show that sGP and VSV-P-N provide a reliable signature of ERVEBO vaccination and support improved Ebola surveillance.

• Respirable Aerosol Production and Reduction of Avian Influenza Transmission Risk during Chicken Processing, Bangladesh
  N. Rimi et al.
• Evaluation of Effectiveness of Autocidal Gravid Ovitraps for Preventing Zika Virus Infection, Puerto Rico, USA
  Z. J. Madewell et al. View Abstract

  Aedes aegypti mosquitoes drive arboviral outbreaks in tropical regions. Zika virus (ZIKV), linked to congenital and neurologic complications, caused a major outbreak in Puerto Rico, USA, in 2016, infecting ≈26% of the population. Autocidal gravid ovitraps (AGOs), pesticide-free devices targeting gravid Ae. aegypti mosquitoes, have been shown to reduce transmission of another arbovirus, chikungunya. During March–May 2017, we conducted a household-based serosurvey in 4 demographically similar communities in southeastern Puerto Rico, 2 with long-term AGO deployment (≈85% coverage) and 2 without, to assess effects of AGOs on ZIKV transmission. Among 271 participants >5 years of age, ZIKV seroprevalence was much lower in intervention than nonintervention communities (9.6% vs. 20.0%). Protective effects were strongest among older adults, larger households (>4 persons), and persons spending more time at home. Although study design and measurement limitations could limit generalizability of results, our findings support AGOs as sustainable nonchemical tools for reducing ZIKV infections.

• Seroprevalence of Crimean-Congo Hemorrhagic Fever Virus Infection in Humans and Domestic Ruminants, Democratic Republic of the Congo
  B. Lombe et al. View Abstract

  Crimean-Congo hemorrhagic fever virus (CCHFV) was first isolated in the Democratic Republic of the Congo (DRC) in 1956. To date, only 3 sporadic human cases have been reported in the DRC, and data on CCHFV infection in livestock, which are key players in transmission, are scant. We conducted a cross-sectional seroepidemiological study on archived human and animal serum samples collected from 25 provinces across the DRC. Samples were tested using an ELISA detecting CCHFV nucleoprotein-specific antibodies. The seroprevalence of CCHFV infection in humans was 4.4% (55/1,239) and in domestic ruminants was 28.9% (322/1,114). High seroprevalences tended to correlate with increased age, specific climate conditions (e.g., tropical monsoon) and vegetation (e.g., mountain savanna) types, and higher elevation (>600 m). Our findings suggest that CCHFV actively circulates in animals and sporadically transmits to humans in the DRC, highlighting the need for continued surveillance of CCHFV infection.

• Geographically Distinct Circulation of Genotype II and III St. Louis Encephalitis Virus, Texas, USA, 2009–2024
  A. R. Kneubehl et al. View Abstract

  We conducted a retrospective genomic surveillance study of St. Louis encephalitis virus (SLEV) in Texas, USA, to determine the genotypes circulating in the region. By using a custom tiled-amplicon assay with Oxford Nanopore sequencing, we generated 63 genomes from SLEV-positive mosquito pools and viral isolates collected during 2009–2024. Phylogenomic analysis revealed temporal overlap of genotype II and III circulation, but with distinct geographic segregation. Genotype II was confined to Gulf Coast counties with sustained local transmission, whereas genotype III was only in north and West Texas, but with persistent circulation and repeated introductions. We identified the earliest known US genotype III sequences, although their phylogenetic placement leaves the entry point of genotype III into the United States unresolved. Our findings emphasize the need for clinical vigilance in West Texas, where SLEV and West Nile virus co-circulate, and suggest the Gulf Coast may be buffered against foreign genotype introduction.

• Accelerated Increase in Candida auris Bloodstream Infections during COVID-19 Pandemic, South Africa
  H. Ismail et al. View Abstract

  The COVID-19 pandemic coincided with rising secondary bloodstream infections (BSIs) from multidrug-resistant organisms, including Candida auris. To assess candidemia trends, we conducted a retrospective analysis of blood culture isolates from public and private laboratories in South Africa taken during January 2019–June 2022. We evaluated weekly aggregated Candida BSI counts and COVID-19 cases using segmented regression within an interrupted time-series framework. In total, 15,393 candidemia cases were identified, 70% from the private sector. C. parapsilosis accounted for 39% of cases, whereas C. auris represented 26%. The proportion of C. auris increased significantly from 17% in 2019 to 31% in 2021 (p<0.01). After the pandemic onset, Candida BSIs rose by 11 cases per week (p = 0.03), largely driven by C. auris (+5 cases/week; p<0.01); peaks coincided with COVID-19 waves. Those results highlight an accelerated shift toward C. auris in Candida BSIs and the urgent need for enhanced surveillance, diagnostics, and infection prevention.

• Transmissibility and Disease Progression of Asymptomatic Mycobacterium Tuberculosis, Lima, Peru
  R. Wang et al.
• Border Region Surveillance of Malaria Drug Resistance, Northern Burundi, 2023–2024
  D. Niyomwungere et al. View Abstract

  To evaluated artemisinin partial resistance (ART-R) in malaria in Burundi, during December 2023–June 2024, we studied 423 children <5 years of age with uncomplicated Plasmodium falciparum malaria in 8 health facilities in the northern part of the country. After artemether/lumefantrine treatment with only the first dose directly observed, 4.5% remained parasitemic on day 3. No pfkelch13 mutations, validated or candidate markers of ART-R, were detected. However, markers of antifolate and 4-aminoquinoline resistance were widespread: the dhfr triple mutant N51I/C59R/S108N was nearly fixed (92%), dhps double and triple mutants were common (41% and 47%), and pfcrt CVIET, associated with chloroquine and amodiaquine resistance, predominated (84%). Geographic differences occurred in day-3 positivity and haplotype frequencies. Although ART-R markers were absent, delayed parasite clearance and near fixation of multidrug-resistant haplotypes serve as a warning. Strengthened efficacy monitoring and regional molecular surveillance are urgently needed to prevent drug-resistant P. falciparum from becoming established in Burundi.

Dispatches

• Chronic Wasting Disease in Farmed Cervids, South Korea, 2001–2024
  Y. Choi et al.
• Panton-Valentine Leukocidin–Encoding CC398 Methicillin-Resistant Staphylococcus aureus, the Netherlands, 2023–2024
  P. van Schelven et al.
• Outbreak of Dengue Virus Serotype 3, Republic of the Marshall Islands, 2019–2021
  T. M. León et al.
• Rapid Spread of Recombinant African Swine Fever Virus Genotypes I and II, Vietnam, 2023–2024
  Y. Kim et al.
• Treatment of Severe Ocular Mpox with Cidofovir and Tecovirimat
  X. BROUSSE et al.
• Recombinant mosaic Coxsackievirus A9 strain associated with severe inflammatory cardiomyopathy in a previously healthy child, Northeastern France, 2024
  A. Lebreil et al.
• Use of nitroxoline for disseminated Acanthamoeba infection presenting as necrotic skin lesions and granulomatous vasculitis in an elderly man on dupilumab
  M. Koshy et al.
• Guillain-Barré Syndrome and Visual Impairment Associated with Emerging Oropouche Virus Lineage, Brazil, 2024
  C. Filho et al.
• Whole Genome Analysis of Treponema pallidum subsp. endemicum Among Men Who Have Sex with Men, Japan, 2020–2023
  Y. Ohama et al.

Photo Quiz

• Photo Quiz
  N. Hoffmann

Research Letters

• Rickettsia lanei Rickettsiosis, Oregon, USA, 2025
  S. G. Ladd-Wilson et al. View Abstract

  Using metagenomic sequencing, we identified a patient infected with Rickettsia lanei who was initially diagnosed with Rocky Mountain spotted fever (RMSF), a clinically similar disease caused by infection with R. rickettsii. Our investigation highlights the importance of clinical, epidemiologic, and laboratory partnerships to leverage the discovery of novel pathogens.

• Seroepidemiologic Study of Oropouche Virus, Amazonas State, Brazil, 2015–2016
  J. Forato et al.
• Acute Febrile Illness Surveillance Similar to Household Serosurvey for Population Immunity Estimates, Dominican Republic, 2021
  E. J. Nilles et al.

Another Dimension

• The Weight of Waiting
  M. Diagne

Etymologia

• Anopheles stephensi [ә-nah′-fuhl-ēz ste′-fen-zī]
  G. Kumar and J. Kaur

About the Cover

• Giovanni Battista Grassi and Malaria
  S. Pozzi and M. A. Riva

Synopses

• Three Fatal Gestational Psittacosis Cases Caused by Chlamydia psittaci Strains Belonging to Closely Related MLST Lineages, Japan
  A. Nishino et al.
• Borna disease virus 1 infection causing fatal meningoencephalomyelitis in wild European hedgehogs in known endemic areas, Germany, 2022 to 2025
  E. Michelakaki et al.

Research

• Zoonotic and Anthroponotic Plasmodium spp. Circulation between Wild Primates and Indigenous Community, Peruvian Amazon, 2007–2020
  G. M. Ulloa et al.
• Frequency, Duration, and Risk Factors for Diagnostic Delays Associated with Coccidioidomycosis
  D. D. Barber et al.
• Investigation of and Response to Autochthonous Dengue, Los Angeles County, California, USA, August–November 2024
  A. M. Vaughan et al. View Abstract

  Dengue is not endemic in the continental United States; most cases occur in returning travelers. During August–November 2024, a total of 14 locally acquired cases of dengue were identified in Los Angeles County, California, USA. Epidemiologic evidence indicates that locally acquired cases occurred in several neighborhoods, suggesting short transmission chains after introductions from returning travelers. In one neighborhood, evidence supported ongoing transmission for up to 7 weeks. Median patient age was 54 (range 5–79) years; 8 (57%) patients were female and 6 (43%) male, and 6 (43%) required hospitalization. Delays in healthcare seeking and diagnoses were noted; median time from symptom onset to specimen collection for dengue testing was 9 (range 2–34) days. Local dengue transmission in Los Angeles County highlights the emerging threat of mosquitoborne disease transmission in nonendemic areas and the need for rapid and coordinated public health and vector control responses to interrupt transmission.

• Updated Genomic Epidemiologic Description of Candida (Candidozyma) auris, United States
  L. A. Parnell et al.

Dispatches

• Detection of Human Rhinovirus B14 from Outbreak of Severe Respiratory Illness among Older Adults, France, 2024
  J. Andreani et al.
• Tropism and Replication Competence of Cattle Influenza A(H5N1) Genotype B3.13 Virus in Human Bronchus and Lung Tissue
  K. Hui et al. View Abstract

  In 2024, influenza A(H5N1) genotype B3.13 viruses emerged from cattle and caused mild spillover infections in humans. Using human bronchus and lung tissue, we evaluated tropism, replication, and pathogenesis of 2 cattle influenza isolates. Those viruses showed moderate replication competence and induced robust proinflammatory responses, suggesting potential risk for human health.

• Genomic Analysis of Sin Nombre Virus Genome Sequences, Northwestern United States, 2023
  G. Rickard et al.
• Retrospective Phylogenetic Analysis of Mayaro Virus, French Guiana, 1996–2024
  A. Lagrave et al.
• Serologic Surveillance of Wildlife in High Pathogenicity Avian Influenza Virus Subtype H5 Hotspot, Northeast Germany, 2023–2025
  A. Günther et al.
• A One Health investigation into a fatal encephalitis caused by pigeon paramyxovirus type 1 (PPMV-1) infection in France
  N. Veyrenche et al.
• Infection and exposure to the human tick-borne relapsing fever agent Borrelia persica in horses in Israel, 2025
  D. Shwartz et al.
• Repeated human cases of Cryptosporidium sp. OTUi in returned travelers: Clinical, molecular, and zoonotic perspectives
  T. Larsen et al.
• Yezo Virus Diversity in Tick-Bitten Patients and Ticks, Russia
  Y. O. Epik et al.

Research Letters

• Genomic Surveillance of Lassa Virus through In-Country Sequencing, Guinea
  J. Camara et al.
• Highly Pathogenic Avian Influenza A(H5N1) Viral RNA in Bovine Semen, California, USA, 2024
  A. Lim et al.
• Herpes Simplex Virus 1 in Trigeminal Ganglia of Trafficked Neotropical Primates
  F. Vilchez-Delgado et al.
• Unmitigated serial interval and intervention efficiency in a school-based outbreak of pertussis, South Korea, 2024
  A. R. Akhmetzhanov et al.

Letters

• Comment on Chagas Disease, an Endemic Disease in the United States
  P. T. Cantey et al.
• Evidence of Rat Hepatitis E Virus Circulation through Wastewater Surveillance, Central Argentina
  F. Abravanel et al.

Books and Media

• The Big One: How We Must Prepare for Future Deadly Pandemics
  C. Dillingham et al.

Etymologia

• Bacteria [bak-tēr′-ē-ә]
  H. Santos-Dutra et al.

Synopsis

• Cerebrospinal Fluid Findings among Patients with Anaplasmosis and Central Nervous Involvement, Minnesota and Wisconsin, USA
  I. Dumic et al.

Books and Media

• Dangerous Miracle: The Astonishing Rise and Looming Disaster of Antibiotics
  J. P. Mills