Suchergebnisse

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) skin and soft-tissue infections (SSTIs) are common among military recruits. Identifying which strains are responsible for SSTI and understanding the underlying transmission dynamics is critical to developing appropriate interventions for this high-risk population. METHODS: A cohort study of US Army Infantry trainees at Fort Benning, GA (June and September 2015). Participants from two training Companies were screened for colonization on multiple anatomic sites throughout the 14-week cycle as well as the time of clinical infection. MRSA+ samples were sequenced with Illumina HiSeq. Multi-locus sequence type (MLST) and virulence genes were identified in silico. Single nucleotide polymorphism (SNP) distances between soldiers' bacteria were compared with assessing for potential transmission. RESULTS: Of 383 soldiers enrolled, 84 (22%) were colonized with MRSA during the study. Forty-two of 84 had a single positive colonization sample, of which 76% were from anatomical sites other than the nares (36% oropharyngeal, 26% perianal, 14% inguinal). Twelve trainees had MRSA SSTI during training (50% had colonization detected prior to or at infection). All were PFGE-type US300 (ST8) and were lukS/lukF-positive. SNP-based phylogenetic analyses and epidemiologic data indicate that most MRSA positives at baseline were due to unique importations from various community origins, suggesting that the ongoing MRSA epidemic is not due to a single endemic strain circulating on base. Following importation, extensive transmission then occurred, with multiple STs implicated. Transmission appeared restricted to within Companies, and predominantly within platoons. CONCLUSION: Frequent colonization at baseline suggests a need for extensive MRSA screening and decolonization upon arrival to base, followed by ongoing infection control measures throughout training to prevent recolonization/infection. As multiple anatomical sites appear to play a role in transmission of MRSA, this may ...

With growing concern of persistent or multiple waves of SARS-CoV-2 in the United States, sensitive and specific SARS-CoV-2 antibody assays remain critical for community and hospital-based SARS-CoV-2 surveillance. Here, we describe the development and application of a multiplex microsphere-based immunoassay (MMIA) for COVD-19 antibody studies, utilizing serum samples from non-human primate SARS-CoV-2 infection models, an archived human sera bank and subjects enrolled at five U.S. military hospitals. The MMIA incorporates prefusion stabilized spike glycoprotein trimers of SARS-CoV-2, SARS-CoV-1, MERS-CoV, and the seasonal human coronaviruses HCoV-HKU1 and HCoV-OC43, into a multiplexing system that enables simultaneous measurement of off-target pre-existing cross-reactive antibodies. We report the sensitivity and specificity performances for this assay strategy at 98% sensitivity and 100% specificity for subject samples collected as early as 10 days after the onset of symptoms. In archival sera collected prior to 2019 and serum samples from subjects PCR negative for SARS-CoV-2, we detected seroprevalence of 72% and 98% for HCoV-HKU1 and HCoV-0C43, respectively. Requiring only 1.25 μL of sera, this approach permitted the simultaneous identification of SARS-CoV-2 seroconversion and polyclonal SARS-CoV-2 IgG antibody responses to SARS-CoV-1 and MERS-CoV, further demonstrating the presence of conserved epitopes in the spike glycoprotein of zoonotic betacoronaviruses. Application of this serology assay in observational studies with serum samples collected from subjects before and after SARS-CoV-2 infection will permit an investigation of the influences of HCoV-induced antibodies on COVID-19 clinical outcomes.

BACKGROUND: We evaluated clinical outcomes, functional burden, and complications 1 month after coronavirus disease 2019 (COVID-19) infection in a prospective US Military Health System (MHS) cohort of active duty, retiree, and dependent populations using serial patient-reported outcome surveys and electronic medical record (EMR) review. METHODS: MHS beneficiaries presenting at 9 sites across the United States with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test, a COVID-19-like illness, or a high-risk SARS-CoV-2 exposure were eligible for enrollment. Medical history and clinical outcomes were collected through structured interviews and International Classification of Diseases–based EMR review. Risk factors associated with hospitalization were determined by multivariate logistic regression. RESULTS: A total of 1202 participants were enrolled. There were 1070 laboratory-confirmed SARS-CoV-2 cases and 132 SARS-CoV-2-negative participants. In the first month post–symptom onset among the SARS-CoV-2-positive cases, there were 212 hospitalizations, 80% requiring oxygen, 20 ICU admissions, and 10 deaths. Risk factors for COVID-19-associated hospitalization included race (increased for Asian, Black, and Hispanic compared with non-Hispanic White), age (age 45–64 and 65+ compared with <45), and obesity (BMI≥30 compared with BMI<30). Over 2% of survey respondents reported the need for supplemental oxygen, and 31% had not returned to normal daily activities at 1 month post–symptom onset. CONCLUSIONS: Older age, reporting Asian, Black, or Hispanic race/ethnicity, and obesity are associated with SARS-CoV-2 hospitalization. A proportion of acute SARS-CoV-2 infections require long-term oxygen therapy; the impact of SARS-CoV-2 infection on short-term functional status was substantial. A significant number of MHS beneficiaries had not yet returned to normal activities by 1 month.