Articles from Emerging Infectious Diseases

Despite earlier attempts to define global health, the discipline’s boundaries are unclear, its priorities defined more by funding from high-income countries from the Global North than by global health trends. Governance and resource allocation are challenged by movements such as decolonizing global health. Inherent contradictions within global health derive from its historical evolution from tropical medicine and international health, as well as recent trends in infectious diseases. Demographic, socioeconomic, and epidemiologic transitions, including the rise in noncommunicable diseases, have eroded the concept of a binary world of developed and developing countries. Competitive tension has emerged between aspirations for global health security and health equity. Dominant principles should focus on vulnerable populations, transnational challenges such as migration and climate change, appropriate prevention and care, and epidemic preparedness and response capacity. As the 2030 target date for the United Nations Sustainable Development Goals approaches, reconceptualization of global health is required, or the discipline risks losing identity and relevance.

Streptococcus pneumoniae infection is considered an uncommon cause of arthritis in adults. To determine the clinical and microbiological characteristics of pneumococcal septic arthritis, we retrospectively studied a large series of cases among adult patients during the 2010–2018 conjugate vaccine era in France. We identified 110 patients (56 women, 54 men; mean age 65 years), and cases included 82 native joint infections and 28 prosthetic joint infections. Most commonly affected were the knee (50/110) and hip (25/110). Concomitant pneumococcal infections were found in 37.2% (38/102) and bacteremia in 57.3% (55/96) of patients, and underlying conditions were noted for 81.4% (83/102). Mortality rate was 9.4% (8/85). The proportion of strains not susceptible to penicillin was 29.1% (32/110). Of the 55 serotyped strains, 31 (56.4%) were covered by standard pneumococcal vaccines; however, several nonvaccine serotypes (mainly 23B, 24F, and 15A) had emerged, for which susceptibility to β-lactams was low.

Rickettsia sibirica mongolitimonae is an emerging cause of tickborne rickettsiosis. Since the bacterium was first documented as a human pathogen in 1996, a total of 69 patients with this infection have been reported in the literature. Because of the rising rate of R. sibirica mongolitimonae infection cases, we evaluated the epidemiologic and clinical features of 29 patients who had R. sibirica mongolitimonae infections confirmed during 2007–2024 at the Center for Rickettsiosis and Arthropod-Borne Diseases, the reference laboratory of San Pedro University Hospital–Center for Biomedical Research of La Rioja, Logroño, Spain. We also reviewed all cases published in the literature during 1996–2024, evaluating features of 94 cases of R. sibirica mongolitimonae infection (89 in Europe, 4 in Africa, and 1 in Asia). Clinicians should consider R. sibirica mongolitimonae as a potential causative agent of rickettsiosis, and doxycycline should be administered promptly to avoid clinical complications.

Reports of mpox are rising in Africa where the disease is endemic and in new countries where the disease has not been previously seen. The 2022 global outbreak of clade II mpox and an ongoing outbreak of the more lethal clade I mpox highlight the pandemic potential for monkeypox virus. Waning population immunity after the cessation of routine immunization for smallpox plays a key role in the changing epidemiologic patterns of mpox. Sustained human-to-human transmission of mpox is occurring widely in the context of insufficient population immunity, fueling genetic mutations that affect the accuracy of some diagnostic tests and that could lead to changing virulence. Additional research should address complex challenges for control of mpox, including improved diagnostics and medical countermeasures. The availability of vaccines should be expanded not only for outbreak response but also for broader routine use for persons in mpox-endemic countries.

We describe an outbreak of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup C in Fiji. We created surveillance case definitions and collected data by using standard investigation forms. Bacterial identification, antimicrobial susceptibility testing, and PCR were performed in Fiji. Molecular testing was conducted at the Microbiological Diagnostic Unit in Melbourne, Victoria, Australia. During January 2016–December 2018, a total of 96 confirmed or probable IMD cases were reported. Of case-patients, 61.5% (59/96) were male and 38.5% (37) female, 84.4% (81) were indigenous people of Fiji, and 70.8% (68) were children <15 years of age. Annual incidence increased from 1.8/100,000 population in 2016 to 5.2/100,000 population in 2018. Serogroup C multilocus serotype 4821 that is resistant to ciprofloxacin was prevalent (62.1%, 41/66). Public health measures, which included targeted mass vaccination with monovalent meningitis C vaccine, were effective in controlling the outbreak. We observed a rapid decline in meningitis C cases in subsequent years.

Evolving technology and the development of new devices that can aerosolize water present a risk for new sources of Legionella bacteria growth and spread within industrial settings. We investigated a cluster of legionellosis among employees of a manufacturing facility in South Carolina, USA, and found 2 unique equipment sources of Legionella bacteria. The cluster of cases took place during August–November 2022; a total of 34 cases of legionellosis, including 15 hospitalizations and 2 deaths, were reported. Legionella pneumophila was isolated from 3 devices: 2 water jet cutters and 1 floor scrubber. L. pneumophila sequence type 36 was identified in environmental isolates and 1 patient specimen, indicating that those devices were the likely source of infection. Remediation was ultimately achieved through the development and implementation of a device-specific water management program. Manufacturing facilities that use aerosol-generating devices should consider maintaining updated Legionella water management programs to prevent Legionella bacterial infections.

Human cases of avian influenza A(H5N2) and A(H5N1) viruses associated with outbreaks in birds and mammals are increasing globally, raising concerns about the possibility of a future avian influenza pandemic. We conducted a systematic review examining 30 reported cases of avian influenza in pregnant women. We found high mortality rates for mothers (90.0%, 27/30) and their babies (86.7%, 26/30) when women were infected with avian influenza virus during pregnancy. Despite being a high-risk population and having worse health outcomes across multiple pandemics, pregnant women are often excluded from vaccine trials. However, as the risk for a new pandemic increases and human vaccines against avian influenza are developed, early inclusion of pregnant women in clinical trials can inform the risk–benefit analysis for both the mother and their newborn infant. Early inclusion of pregnant women in public health vaccination programs is vital for protecting this high-risk population.

Middle East respiratory syndrome coronavirus (MERS-CoV) circulates in dromedary camels in the Arabian Peninsula and occasionally causes spillover infections in humans. MERS-CoV diversity is poorly understood because of the lack of sampling during the COVID-19 pandemic. We collected 558 swab samples from dromedary camels in Saudi Arabia during November 2023–January 2024. We found 39% were positive for MERS-CoV RNA by reverse transcription PCR. We sequenced 42 MERS-CoVs and 7 human 229E-related coronaviruses from camel swab samples by using high-throughput sequencing. Sequences from both viruses formed monophyletic clades apical to recently available genomes. MERS-CoV sequences were most similar to B5 lineage sequences and harbored unique genetic features, including novel amino acid polymorphisms in the spike protein. Further characterization will be required to understand their effects. MERS-CoV spillover into humans poses considerable public health concerns. Our findings indicate surveillance and phenotypic studies are needed to identify and monitor MERS-CoV pandemic potential.

Escherichia coli producing OXA-48–like carbapenemases (OXA-EC) is considered a high-risk pathogen spread primarily in the community in low- and middle-income countries and nosocomially in high-income countries. We investigated the emergence and spread of OXA-EC in Israel, a high-income country with strong carbapenemase-directed infection control in healthcare institutions, by conducting a population-based study using data and isolates from the national surveillance system. A total of 3,510 incident cases of OXA-EC occurred during 2007–2023. During 2016–2023, annual cases rose from 41 to 1,524 and nonnosocomial cases rose from 39% to 57%. Sixty-three sequenced isolates belonged to 20 sequence types (STs) and had 3 bla_OXA alleles (bla_OXA-244, bla_OXA-48, and bla_OXA-181); 71% were chromosomally encoded, and 29% were plasmid-encoded. Nosocomially and non–nosocomially acquired isolates belonged to the same STs and alleles. Most outbreaks involved multiple STs and could only partially be explained by plasmid dissemination. Measures for confronting OXA-EC might need reconsideration.

We collected social contact data in Greece to measure contact patterns before (January 2020) and during the COVID-19 pandemic (March 2020–October 2021) and assess the effects of social distancing over time. During lockdowns, mean daily contacts decreased to 2.8–5.9 (mean prepandemic 20.4). Persons >65 years of age retained the fewest contacts during the pandemic (2.1–4.1). Compared with the first lockdown (March–April 2020), the second lockdown (November–December 2020) and third lockdown (April 2021) showed higher numbers of contacts (incidence rate ratio 1.50 [95% CI 1.27–1.76] in second lockdown and 2.19 [95% CI 1.86–2.58] in third lockdown). In 2021, an increase in contacts was apparent, which persisted during the April 2021 lockdown among persons 18–64 years of age. Our study provides evidence of the waning observance of physical distancing. Effective risk communication alongside targeted social distancing could offer alternatives to repeated lockdowns.

Neisseria meningitidis is a common commensal bacterium of the nasopharynx that can cause invasive meningococcal disease (IMD). In comparison, N. gonorrhoeae is always a pathogen usually limited to mucosal sites. However, increased evidence for overlapping clinical syndromes is emerging. We compared N. meningitidis samples from a urogenital outbreak in Australia with sequences from the United States and other countries. We conducted phylogenetic analyses to assess relatedness and examine for genomic changes associated with meningococcal adaptation; we collated a total of 255 serogroup Y (MenY), sequence type (ST) 1466 isolate assemblies. Most urogenital isolates originated from Australia; those isolates formed a distinct clade, most closely related genomically to recent US IMD isolates. No specific genomic changes suggested niche adaptation or associated clinical manifestations. The MenY ST1466 N. meningitidis isolates circulating in Australia and the United States are capable of causing both urethritis and invasive meningococcal disease.

Few sources have reported empirical social contact data from resource-poor settings. To address this shortfall, we recruited 1,363 participants from rural and urban areas of Mozambique during the COVID-19 pandemic, determining age, sex, and relation to the contact for each person. Participants reported a mean of 8.3 (95% CI 8.0–8.6) contacts per person. The mean contact rates were higher in the rural site compared with the urban site (9.8 vs 6.8; p<0.01). Using mathematical models, we noted higher vaccine effects in the rural site when comparing empirical (32%) with synthetic (29%) contact matrices and lower corresponding vaccine effects in the urban site (32% vs 35%). Those effects were prominent in younger (0–9 years) and older (≥60 years) persons. Our work highlights the importance of empirical data, showing differences in contact rates and patterns between rural and urban sites in Mozambique and their nonnegligible effects in modeling potential effects of vaccine interventions.

Albendazole/ivermectin combination therapy is a promising alternative to benzimidazole monotherapy alone for Trichuris trichiura control. We used fecal DNA metabarcoding to genetically characterize Trichuris spp. populations in patient samples from Côte d’Ivoire showing lower (egg reduction rate <70%) albendazole/ivermectin sensitivity than those from Laos and Tanzania (egg reduction rates >98%). Internal transcribed spacer (ITS) 1 and ITS2 metabarcoding revealed the entire detected Côte d'Ivoire Trichuris population was phylogenetically distinct from T. trichiura found in Laos and Tanzania and was more closely related to T. suis. Mitochondrial genome sequencing of 8 adult Trichuris worms from Côte d’Ivoire confirmed their species-level differentiation. Sequences from human patients in Cameroon and Uganda and 3 captive nonhuman primates suggest this novel species, T. incognita, is distributed beyond Côte d'Ivoire and has zoonotic potential. Continued surveillance by using fecal DNA metabarcoding will be needed to determine Trichuris spp. geographic distribution and control strategies.

Since 2016, epizootics of highly pathogenic avian influenza (HPAI) virus have threatened the poultry sector in Europe. Because conventional prevention and control measures alone were insufficient in some contexts, the European Commission authorized poultry vaccination in 2023. Subsequently, France launched a nationwide duck vaccination campaign combined with a comprehensive surveillance plan. We used a mathematical model to simulate the transmission of HPAI viruses in vaccinated duck flocks and assess the effectiveness of a wide range of surveillance strategies. Sampling and testing dead ducks every week (enhanced passive surveillance) was the most sensitive (≈90%) and the most timely strategy. Active surveillance through monthly testing of a cross-sectional sample of live ducks was the least sensitive and timely strategy. Thus, we advise focusing HPAI surveillance efforts on enhanced passive surveillance and reducing active surveillance of live ducks.

Cefiderocol (FDC), a siderophore-cephalosporin conjugate, is the newest option for treating infection with carbapenem-resistant gram-negative bacteria. We identified a novel mechanism contributing to decreased FDC susceptibility in Klebsiella pneumoniae clinical isolates. The mechanism involves 2 coresident plasmids: pKpQIL, carrying variants of bla_KPC carbapenemase gene, and pKPN, carrying the ferric citrate transport (FEC) system. We observed increasing FDC MICs in an Escherichia coli model system carrying different natural pKpQIL plasmids, encoding different K. pneumoniae carbapenemase (KPC) variants, in combination with a conjugative low copy number vector carrying the fec gene cluster from pKPN. We observed transcriptional repression of fiu, cirA, fepA, and fhuA siderophore receptor genes in bla_KPC–fec–E. coli cells treated with ferric citrate. Screening of 27,793 K. pneumoniae whole-genome sequences revealed that the fec cluster occurs frequently in some globally distributed different KPC-producing K. pneumoniae clones (sequence types 258, 14, 45, and 512), contributing to reduced FDC susceptibility.

We report highly pathogenic avian influenza A(H5N1) virus clade 2.3.2.1a in a child traveler returning to Australia from India. The virus was a previously unreported reassortant consisting of clade 2.3.2.1a, 2.3.4.4b, and wild bird low pathogenicity avian influenza gene segments. These findings highlight surveillance gaps in South Asia.

We report a fatal case of Crimean-Congo hemorrhagic fever in Portugal. An 83-year-old man, initially suspected of having Mediterranean spotted fever, was later confirmed to have Crimean-Congo hemorrhagic fever by the detection of viral genome in the patient's serum and the presence of specific IgM antibodies.

Mpox is a zoonotic disease caused by the monkeypox virus. We report on human mpox cases in Uganda identified by PCR and confirmed by deep sequencing. Phylogenetic analysis revealed clustering with other clade Ib sequences associated with recent outbreaks in the Democratic Republic of the Congo.

During September–October 2021, group B Streptococcus bloodstream infections surged among patients hospitalized in Hong Kong. Of 95 cases, 57 were caused by the hypervirulent strain sequence type 283, which at the time was also found in freshwater fish and wet market environments and thus poses a transmission threat.

Mammarenaviruses are noteworthy zoonotic pathogens, and the main reservoirs are rodent species. We report the detection of a novel mammarenavirus in 6/183 (3.3%) in necropsied European hedgehogs (Erinaceus europaeus) collected in Italy. The whole-genome sequence obtained for 4 strains revealed a marked genetic diversity but a monophyletic origin.

We conducted a survey for domestic cat hepadnavirus, an analog of human hepatitis B virus, in the endangered felid species Iberian lynx. Results revealed specific antibodies in 32.3% of serum samples and DNA in 0.5% of available liver samples. Phylogenetically, the virus segregated apart from other Europe strains of the virus.

We report a cluster of infections with genetically related toxigenic Corynebacterium diphtheriae linked to an outbreak among asylum seekers in Switzerland that subsequently affected patients without known exposure. This discovery highlights the importance of rapid, interdisciplinary outbreak investigations and regular vaccination status assessment, especially in elderly populations with waning immunity.

Using a prion amplification assay, we identified prions in tissues from wild pigs (Sus scrofa) living in areas of the United States with variable chronic wasting disease (CWD) epidemiology. Our findings indicate that scavenging swine could play a role in disseminating CWD and could therefore influence its epidemiology, geographic distribution, and interspecies spread.

To trace evolution of Panton-Valentine leucocidin–positive clonal complex 398 methicillin-resistant Staphylococcus aureus (MRSA) in the Czech Republic, we tested 103 MRSA isolates from humans. Five (4.9%) were Panton-Valentine leucocidin–positive clonal complex 398, sequence types 1232 and 9181. Spread to the Czech Republic may result from travel to or from other countries.

During 2014–2022, only Plasmodium falciparum malaria cases were reported in the Comoro Islands. We report a fatal case of mixed Plasmodium malaria infection in a traveler returning from the Comoros to Colombia in 2024, highlighting the need to strengthen laboratory detection and identification of Plasmodium spp. in sub-Saharan Africa.

We report the genomic analysis from early equine cases of the Western equine encephalitis virus outbreak during 2023–2024 in Uruguay. Sequences are related to a viral isolate from an outbreak in 1958 in Argentina. A viral origin from South America or continuous enzootic circulation with infrequent spillover is possible.

Recent outbreaks of influenza A(H5N1) have affected many mammal species. We report serologic evidence of H5N1 virus infection in horses in Mongolia. Because H3N8 equine influenza virus is endemic in many countries, horses should be monitored to prevent reassortment between equine and avian influenza viruses with unknown consequences.

A Salmonella enterica serovar Abony outbreak occurred during January–April 2024 in Chile. Genomic evidence indicated that the outbreak strain was a clone of reference strain WDCM 00029, which is routinely used in microbiological quality control tests. When rare or unreported serovars cause human infections, clinicians and health authorities should request strain characterization.

We identified Prototheca spp. microalga in ocular samples of a cat in Spain with nontreatable endogenous endophthalmitis. Within 2 years, the eye lesions progressively worsened and neurologic signs appeared, suggesting systemic spread of the infection. On multitarget sequence analysis, the feline pathogen could not be assigned to any known Prototheca species.

We describe 157 cases of Trichophyton indotineae infection in the United Kingdom, mostly in patients linked to southern Asia. T. indotineae is spreading in the United Kingdom and accounts for 38% of dermatophyte isolates referred to the UK National Mycology Reference Laboratory. Clinicians should suspect T. indotineae in tinea corporis cases.

Vancomycin-resistant Staphylococcus aureus (VRSA) is a rare but serious public health concern. We describe a VRSA case in North Carolina, USA. The isolate from the case belonged to the USA600 lineage and clonal complex 45. No transmission was identified. Confirmed VRSA cases should include a thorough investigation and public health response.

We report a low (38.7%; p<0.0001) level of IgG seroconversion in patients who were positive for measles virus IgM in the Republic of Congo, despite a history of vaccination. Considering this country’s recurring measles epidemics, more effective immunization strategies, including vaccine delivery methods, are needed to prevent measles outbreaks.

We show that human myxovirus resistance protein 1 (MxA) suppresses replication of highly pathogenic avian influenza A(H5N1) viruses isolated from mammals in vitro and in MxA-transgenic mice. However, H5N1 can evade MxA restriction through replacement of individual viral polymerase complex components from a human-adapted MxA-resistant strain in vitro.

Latin America is experiencing an unprecedented dengue outbreak, causing an increased health burden. We document the cocirculation of dengue viruses 1–4 in Putumayo, a remote, underserved region at the border between Ecuador and Colombia. Dengue circulation in this largely unexplored territory represents a threat to public health in Putumayo and neighboring areas.

Hypervirulent Klebsiella pneumoniae (hvKp) can cause life-threatening infections in healthy community members. HvKp infections often involve multiple sites, some of which are unusual for classical K. pneumoniae (cKp) infections, such as the central nervous system, eyes, and fascia. The acquisition of antimicrobial resistance by hvKp has resulted in concerns of an emerging superbug. This concern is magnified by increasing geographic dissemination and healthcare associated infections. Currently, diagnostic testing to differentiate hvKp from cKp is lacking, causing challenges for clinical care, surveillance, and research. Although imperfect, the detection of all 5 of the biomarkers iucA, iroB, peg-344, rmpA, and rmpA2 is the most accurate and pragmatic means to identify hvKp. We propose a working definition for hvKp that will enhance accuracy for diagnosis and surveillance, which will aid in preventing the spread of hvKp.

Event management systems (EMS) are key tools for epidemic intelligence, integrating surveillance signals and incident response, although international standards to inform development are lacking. We describe the Nigeria Centre for Disease Control and Prevention (NCDC) SITAware, a software capable of operating with low internet bandwidth to generate notifications, reports, and spatiotemporal dashboards and provide event-level data for real-time accountability and postevent learning. SITAware was enabled by local institutional ownership, co-created at low cost, and integrated into existing workflows. In 2022, SITAware was used to manage ≈300 incidents, and NCDC implemented it subnationally. NCDC’s experience may inform EMS development and implementation in similar settings.

Since the severe acute respiratory syndrome outbreak in 2003, China has invested substantial efforts in promoting scientific and technological advances for medical countermeasures against high-threat pathogens. The examination of China’s landscape identifies progress and gaps in research and development (R&D) and also highlights management and regulatory issues that should be of concern to other countries. Our study examined the current state of R&D of medical countermeasures in China during 1990–2022. The findings showed a robust and diversified pipeline responding quickly to disease outbreaks and policy changes. However, proactive and highly innovative candidates are limited, and a large proportion of vaccines and drugs stagnate at the early development stage. A paradigm shift involving a preemptive R&D agenda and persistent investment, innovative technology development, and accelerated research translation is urgently needed to prepare for the next pandemic.

Rickettsia sibirica mongolitimonae is an emerging cause of tickborne rickettsiosis. Since the bacterium was first documented as a human pathogen in 1996, a total of 69 patients with this infection have been reported in the literature. Because of the rising rate of R. sibirica mongolitimonae infection cases, we evaluated the epidemiologic and clinical features of 29 patients who had R. sibirica mongolitimonae infections confirmed during 2007–2024 at the Center for Rickettsiosis and Arthropod-Borne Diseases, the reference laboratory of San Pedro University Hospital–Center for Biomedical Research of La Rioja, Logroño, Spain. We also reviewed all cases published in the literature during 1996–2024, evaluating features of 94 cases of R. sibirica mongolitimonae infection (89 in Europe, 4 in Africa, and 1 in Asia). Clinicians should consider R. sibirica mongolitimonae as a potential causative agent of rickettsiosis, and doxycycline should be administered promptly to avoid clinical complications.

Streptococcus pneumoniae infection is considered an uncommon cause of arthritis in adults. To determine the clinical and microbiological characteristics of pneumococcal septic arthritis, we retrospectively studied a large series of cases among adult patients during the 2010–2018 conjugate vaccine era in France. We identified 110 patients (56 women, 54 men; mean age 65 years), and cases included 82 native joint infections and 28 prosthetic joint infections. Most commonly affected were the knee (50/110) and hip (25/110). Concomitant pneumococcal infections were found in 37.2% (38/102) and bacteremia in 57.3% (55/96) of patients, and underlying conditions were noted for 81.4% (83/102). Mortality rate was 9.4% (8/85). The proportion of strains not susceptible to penicillin was 29.1% (32/110). Of the 55 serotyped strains, 31 (56.4%) were covered by standard pneumococcal vaccines; however, several nonvaccine serotypes (mainly 23B, 24F, and 15A) had emerged, for which susceptibility to β-lactams was low.

The Ebola virus disease (EVD) outbreak of 2013–2016 was large, leaving in its wake an estimated 17,000 survivors in West Africa. Uveitis is one of the most common ophthalmic manifestations of EVD, but long-term follow-up in the at-risk population is lacking. We conducted a retrospective cross-sectional study of 521 EVD survivors from Sierra Leone who underwent comprehensive ophthalmic examination a median of 1,289 days, or ≈3.5 years, after discharge from Ebola treatment units. The most common ophthalmic findings were cataracts (117 eyes, 11.2%), uveitis (86 eyes, 8.3%), dry eyes (81 eyes, 7.8%), and chorioretinal scar (68 eyes, 6.5%). EVD survivors with cataracts, uveitis, optic neuropathy, and corneal scar were more likely to have vision impairment, defined as Snellen visual acuity worse than 20/50. Results of our study highlight the need for ongoing vision care in EVD survivors.

Congregate homeless shelters are disproportionately affected by infectious disease outbreaks. We describe enterovirus epidemiology across 23 adult and family shelters in King County, Washington, USA, during October 2019–May 2021, by using repeated cross-sectional respiratory illness and environmental surveillance and viral genome sequencing. Among 3,281 participants >3 months of age, we identified coxsackievirus A21 (CVA21) in 39 adult residents (3.0% [95% CI 1.9%–4.8%] detection) across 7 shelters during October 2019–February 2020. We identified enterovirus D68 (EV-D68) in 5 adult residents in 2 shelters during October–November 2019. Of 812 environmental samples, 1 was EV-D68–positive and 5 were CVA21–positive. Other enteroviruses detected among residents, but not in environmental samples, included coxsackievirus A6/A4 in 3 children. No enteroviruses were detected during April 2020–May 2021. Phylogenetically clustered CVA21 and EV-D68 cases occurred in some shelters. Some shelters also hosted multiple CVA21 lineages.

Mycobacterium abscessus infection is challenging to treat. Extrapulmonary M. abscessus infections (EP-MAB) are less common than pulmonary M. abscessus infections. To evaluate treatment regimens, we retrospectively analyzed consecutive microbiologically confirmed EP-MAB cases diagnosed in France during 2012–2020. We studied 45 patients with EP-MAB, including 14 bone and joint infections, 10 skin and soft tissue infections, and 8 lymph node infections. Most (62%) patients had no reported immunodeficiency. In 27 patients, EP-MAB followed healthcare-associated (44%) or environmental (16%) injuries. Of the 45 isolates, 25 were subspecies abscessus, 10 bolletii, and 9 massiliense; 1 was unidentified. Cure was achieved for 36 (80%) patients who received a median antimicrobial regimen of 6 months; 22 (55%) also underwent surgery. Four patients died, and 5 were unavailable for follow-up. EP-MAB predominantly affects immunocompetent patients after an injury; outcomes are favorable. We propose a >6-month regimen of antimicrobial therapy with consideration for surgery and regular patient reassessment.

Pasteurella spp. can cause fatal zoonotic infections in humans. We performed a multicenter study to investigate the prevalence and clinical features of Pasteurella infections in South Korea during 2018‒2022. We also conducted a collaborative systematic review and meta-analysis of the global burden of Pasteurella bacteremia. The study included 283 cases found an increasing trend in Pasteurella infections. Blood cultures were positive in 8/35 (22.9%) cases sampled, for overall bacteremia-associated rate of 2.8% (8/283). Aging was a significant risk factor for bacteremia (odds ratio 1.05 [95% CI 1.01–1.10]), according to multivariate analyses. For the meta-analysis, we included a total of 2,012 cases from 10 studies. The pooled prevalence of bacteremia was 12.4% (95% CI 7.3%–18.6%) and of mortality 8.4% (95% CI 2.7%–16.5%). Our findings reflect the need for greater understanding of the increase in Pasteurella infections and the global burden of Pasteurella bacteremia to determine appropriate case management.

We investigated differences in risk factors and preventive behaviors by age and sex among persons with reported Lyme disease in Ontario, Canada, during 2015–2022. Incidence rates peaked among children 5–9 and adults 50–79 years of age. Median age was higher for female than male case-patients (54 vs. 51 years). Male case-patients reported more activity in wooded and tall grass areas than did female case-patients; fewer male case-patients reported sharing living space with outdoor-exposed companion animals. As age increased, more case-patients reported activity in blacklegged tick habitats, exposure to ticks, and wearing adequate clothing, but fewer reported sharing living space with outdoor-exposed companion animals. Adoption of preventive behaviors was relatively low and did not differ by sex. Male case-patients, children 5–9 years of age and their parents or caregivers, and adults >59 years of age represent populations that would benefit from tailored public health messaging on Lyme disease prevention.

We conducted a prospective study of 159 cases of Streptococcus dysgalactiae subspecies equisimilis (SDSE) bacteremia in 157 patients at 2 hospitals in Finland during November 2015–November 2019. Cellulitis was associated with nonsevere disease (p = 0.008); necrotizing fasciitis was associated with severe disease (p = 0.004). Fifty percent of patients had >1 clinical characteristic associated with risk for death. The case-fatality rate was 6%, and 7% of patients were treated in an intensive care unit. Blood leukocyte counts on days 2 (p = 0.032) and 3 (p = 0.020) and C-reactive protein levels on days 3 (p = 0.030) and 4 (p = 0.009) after admission were predictors of severe disease. The Pitt bacteremia score was an accurate predictor of death. Using the Pitt bacteremia score, leukocyte counts, and CRP responses during initial treatment can improve treatment strategies and survival for patients with SDSE.

Evidence on mortality rates and causes of death associated with extrapulmonary nontuberculous mycobacteria (NTM) infection is limited. This nationwide register-based study in Denmark used diagnostic codes to match adult patients with extrapulmonary NTM infection 1:4 to controls. During 2000–2017, we identified 485 patients, who had significantly more comorbidities than controls. The 5-year mortality rate for patients was 26.8% (95% CI 23.1%–31.0%) and for controls, 10.9% (95% CI 9.6%–12.4%). The median age at death was 76 (interquartile range 63–85) years for patients and 84 (interquartile range 73–90) years for controls. The adjusted hazard rate of death for patients was 1.34 (95% CI 1.10–1.63; p = 0.004). Patients and controls mainly died of cardiovascular disease and solid malignant neoplasms. Hematologic malignancies and HIV were more frequently causes of death in patients. Mortality rates are substantial among patients with extrapulmonary NTM infection, predominantly caused by underlying conditions.

Human infections with Corynebacterium diphtheriae species complex (CdSC) bacteria were rare in French Guiana until 2016, when the number of cases diagnosed increased. We conducted an epidemiologic, multicenter, retrospective study of all human CdSC infections diagnosed in French Guiana during January 1, 2016–December 31, 2021. A total of 64 infectious episodes were observed in 60 patients; 61 infections were caused by C. diphtheriae and 3 by C. ulcerans. Estimated incidence increased from 0.7 cases/100,000 population in 2016 to 7.7 cases/100,000 population in 2021. The mean patient age was 30.4 (+23.7) years, and male-to-female ratio was 1.7:1 (38/22). Of the 61 C. diphtheriae isolates, 5 tested positive for the diphtheria toxin gene, and all results were negative by Elek test; 95% (61/64) of cases were cutaneous, including the C. ulcerans cases. The increase in reported human infections underscores the need to raise awareness among frontline healthcare practitioners to improve prevention.

Archaea represent a separate domain of life, next to bacteria and eukarya. As components of the human microbiome, archaea have been associated with various diseases, including periodontitis, endodontic infections, small intestinal bacterial overgrowth, and urogenital tract infections. Archaea are generally considered nonpathogenic; the reasons are speculative because of limited knowledge and gene annotation challenges. Nevertheless, archaeal syntrophic principles that shape global microbial networks aid both archaea and potentially pathogenic bacteria. Evaluating archaea interactions remains challenging, requiring clinical studies on inflammatory potential and the effects of archaeal metabolism. Establishing a culture collection is crucial for investigating archaea functions within the human microbiome, which could improve health outcomes in infectious diseases. We summarize potential reasons for archaeal nonpathogenicity, assess the association with infectious diseases in humans, and discuss the necessary experimental steps to enable mechanistic studies involving archaea.

Xenotransplantation, transplantation into humans of vascularized organs or viable cells from nonhuman species, is a potential solution to shortages of transplantable human organs. Among challenges to application of clinical xenotransplantation are unknown risks of transmission of animal microbes to immunosuppressed recipients or the community. Experience in allotransplantation and in preclinical models suggests that viral infections are the greatest concern. Worldwide, the distribution of swine pathogens is heterogeneous and cannot be fully controlled by international agricultural regulations. It is possible to screen source animals for potential human pathogens before procuring organs in a manner not possible within the time available for surveillance testing in allotransplantation. Infection control measures require microbiological assays for surveillance of source animals and xenograft recipients and research into zoonotic potential of porcine organisms. Available data suggest that infectious risks of xenotransplantation are manageable and that clinical trials can advance with appropriate protocols for microbiological monitoring of source animals and recipients.

We conducted surveillance for carbapenem-resistant Enterobacterales (CRE) during 2016–2020 at 10 US sites and extended-spectrum β-lactamase–producing Enterobacterales (ESBL-E) during 2019–2020 at 6 US sites. Among 159 CRE cases in children (median age 5 years), CRE was isolated from urine for 131 (82.4%) and blood from 20 (12.6%). Annual CRE incidence rate (cases/100,000 population) was 0.47–0.87. Among 207 ESBL-E cases in children (median age 6 years), ESBL-E was isolated from urine of 196 (94.7%) and blood of 8 (3.9%). Annual ESBL-E incidence rate was 26.5 in 2019 and 19.63 in 2020. CRE and ESBL-E rates were >2-fold higher among infants than other age groups. Most CRE and ESBL-E cases were healthcare-associated community-onset (68 [43.0%] for CRE vs. 40 [23.7%] for ESBL-E) or community-associated (43 [27.2%] for CRE vs. 109 [64.5%] for ESBL-E). Programs to detect, prevent, and treat multidrug-resistant infections must include pediatric populations (particularly the youngest) and outpatient settings.

Crimean-Congo hemorrhagic fever (CCHF) is a tickborne infection that can range from asymptomatic to fatal and has been described in >30 countries. Early identification and isolation of patients with suspected or confirmed CCHF and the use of appropriate prevention and control measures are essential for preventing human-to-human transmission. Here, we provide an overview of the epidemiology, clinical features, and prevention and control of CCHF. CCHF poses a continued public health threat given its wide geographic distribution, potential to spread to new regions, propensity for genetic variability, and potential for severe and fatal illness, in addition to the limited medical countermeasures for prophylaxis and treatment. A high index of suspicion, comprehensive travel and epidemiologic history, and clinical evaluation are essential for prompt diagnosis. Infection control measures can be effective in reducing the risk for transmission but require correct and consistent application.

Crimean-Congo hemorrhagic fever virus (CCHFV) is the most geographically widespread tickborne viral infection worldwide and has a fatality rate of up to 62%. Despite its widespread range and high fatality rate, no vaccines or treatments are currently approved by regulatory agencies in the United States or Europe. Supportive treatment remains the standard of care, but the use of antiviral medications developed for other viral infections have been considered. We reviewed published literature to summarize the main aspects of CCHFV infection in humans. We provide an overview of diagnostic testing and management and medical countermeasures, including investigational vaccines and limited therapeutics. CCHFV continues to pose a public health threat because of its wide geographic distribution, potential to spread to new regions, propensity for genetic variability, potential for severe and fatal illness, and limited medical countermeasures for prophylaxis and treatment. Clinicians should become familiar with available diagnostic and management tools for CCHFV infections in humans.

During October 2021–June 2023, a total of 392 cases of acute hepatitis of unknown etiology in children in the United States were reported to Centers for Disease Control and Prevention as part of national surveillance. We describe demographic and clinical characteristics, including potential involvement of adenovirus in development of acute hepatitis, of 8 fatally ill children who met reporting criteria. The children had diverse courses of illness. Two children were immunocompromised when initially brought for care. Four children tested positive for adenovirus in multiple specimen types, including 2 for whom typing was completed. One adenovirus-positive child had no known underlying conditions, supporting a potential relationship between adenovirus and acute hepatitis in previously healthy children. Our findings emphasize the importance of continued investigation to determine the mechanism of liver injury and appropriate treatment. Testing for adenovirus in similar cases could elucidate the role of the virus.

In 2022, concurrent outbreaks of hepatitis A, invasive meningococcal disease (IMD), and mpox were identified in Florida, USA, primarily among men who have sex with men. The hepatitis A outbreak (153 cases) was associated with hepatitis A virus genotype IA. The IMD outbreak (44 cases) was associated with Neisseria meningitidis serogroup C, sequence type 11, clonal complex 11. The mpox outbreak in Florida (2,845 cases) was part of a global epidemic. The hepatitis A and IMD outbreaks were concentrated in Central Florida and peaked during March–­June, whereas mpox cases were more heavily concentrated in South Florida and had peak incidence in August. HIV infection was more common (52%) among mpox cases than among hepatitis A (21%) or IMD (34%) cases. Where feasible, vaccination against hepatitis A, meningococcal disease, and mpox should be encouraged among at-risk groups and offered along with program services that target those groups.

Disseminated leishmaniasis (DL) is an emergent severe disease manifesting with multiple lesions. To determine the relationship between immune response and clinical and therapeutic outcomes, we studied 101 DL and 101 cutaneous leishmaniasis (CL) cases and determined cytokines and chemokines in supernatants of mononuclear cells stimulated with leishmania antigen. Patients were treated with meglumine antimoniate (20 mg/kg) for 20 days (CL) or 30 days (DL); 19 DL patients were instead treated with amphotericin B, miltefosine, or miltefosine and meglumine antimoniate. High levels of chemokine ligand 9 were associated with more severe DL. The cure rate for meglumine antimoniate was low for both DL (44%) and CL (60%), but healing time was longer in DL (p = 0.003). The lowest cure rate (22%) was found in DL patients with >100 lesions. However, meglumine antimoniate/miltefosine treatment cured all DL patients who received it; therefore, that combination should be considered as first choice therapy.

Streptococcus suis, a zoonotic bacterial pathogen circulated through swine, can cause severe infections in humans. Because human S. suis infections are not notifiable in most countries, incidence is underestimated. We aimed to increase insight into the molecular epidemiology of human S. suis infections in Europe. To procure data, we surveyed 7 reference laboratories and performed a systematic review of the scientific literature. We identified 236 cases of human S. suis infection from those sources and an additional 87 by scanning gray literature. We performed whole-genome sequencing to type 46 zoonotic S. suis isolates and combined them with 28 publicly available genomes in a core-genome phylogeny. Clonal complex (CC) 1 isolates accounted for 87% of typed human infections; CC20, CC25, CC87, and CC94 also caused infections. Emergence of diverse zoonotic clades and notable severity of illness in humans support classifying S. suis infection as a notifiable condition.

During January–August 2021, the Community Prevalence of SARS-CoV-2 Study used time/location sampling to recruit a cross-sectional, population-based cohort to estimate SARS-CoV-2 seroprevalence and nasal swab sample PCR positivity across 15 US communities. Survey-weighted estimates of SARS-CoV-2 infection and vaccine willingness among participants at each site were compared within demographic groups by using linear regression models with inverse variance weighting. Among 22,284 persons >2 months of age and older, median prevalence of infection (prior, active, or both) was 12.9% across sites and similar across age groups. Within each site, average prevalence of infection was 3 percentage points higher for Black than White persons and average vaccine willingness was 10 percentage points lower for Black than White persons and 7 percentage points lower for Black persons than for persons in other racial groups. The higher prevalence of SARS-CoV-2 infection among groups with lower vaccine willingness highlights the disparate effect of COVID-19 and its complications.

Invasive fusariosis can be life-threatening, especially in immunocompromised patients who require intensive care unit (ICU) admission. We conducted a multicenter retrospective study to describe clinical and biologic characteristics, patient outcomes, and factors associated with death and response to antifungal therapy. We identified 55 patients with invasive fusariosis from 16 ICUs in France during 2002­–­­2020. The mortality rate was high (56%). Fusariosis-related pneumonia occurred in 76% of patients, often leading to acute respiratory failure. Factors associated with death included elevated sequential organ failure assessment score at ICU admission or history of allogeneic hematopoietic stem cell transplantation or hematologic malignancies. Neither voriconazole treatment nor disseminated fusariosis were strongly associated with response to therapy. Invasive fusariosis can lead to multiorgan failure and is associated with high mortality rates in ICUs. Clinicians should closely monitor ICU patients with a history of hematologic malignancies or stem cell transplantation because of higher risk for death.