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BACKGROUND: Methicillin-susceptible Staphylococcus aureus (MSSA) is a common cause of skin and soft-tissue infection (SSTI). MSSA genomic epidemiology data are limited. We used whole-genome sequencing (WGS) to examine MSSA strain diversity among military trainees, a group known to be at high risk for S. aureus infection and carriage. METHODS: From July 2012 to December 2014, we conducted a prospective SSTI case–control study among US Army trainees at Fort Benning, GA. Thereafter, we identified MSSA SSTI clusters within select military training classes and performed WGS on clinical and colonizing isolates. We analyzed epidemiologic, clinical, genomic, and phylogenetic data in order to evaluate MSSA strain diversity and patterns of disease transmission. RESULTS: A total of 67 SSTI cases from 15 training classes were identified. The median (range) number of cases per class was 4 (3–10). Cases presented for care after a median of 39 (6–101) days of training. Of the 67 cases, 42 (63%) were colonized with MSSA at ≥1 anatomic site. A total of 78 MSSA colonizing isolates were identified at the time trainees presented for clinical care; colonizing isolates were found in the nares (37%), throat (31%), inguinal region (21%), and perianal region (12%). Multilocus sequence typing (MLST) assigned 128 (88%) isolates to 20 known types and 17 isolates to novel types. Among clinical isolates, 60 (90%) were assigned to known types. Sequence Type (ST) 8 was the most frequent type, accounting for 45% and 35% of clinical and colonizing isolates, respectively. The phylogenetic tree of isolates revealed seven major clusters, some of which were composed of a diversity of training classes, specimen types, and STs. These major clusters were further segregated into 15 sub-clusters where there was considerable diversity in intrahost variation. CONCLUSION: Genomic characterization of MSSA infection and colonization isolates among congregate military trainees revealed a broad diversity of strains. There was a clear clonal origin and ...

A cluster-randomized trial evaluating the effectiveness of chlorhexidine glucotiate-impregnated wipes against skin and soft tissue infections (SSTIs) and colonization with methicillin-resistant Staphylococcus aureas (MRSA) was conducted among military recruits attending Officer Candidate School at Marine Corps Base Quantico, Virginia. Participants were instructed to use the wipes thrice weekly and were monitored daily for SSTI. Surveys assessed frequency of wipe use as well as knowledge and attitudes regarding MRSA SSTI. Use of chlorhexidine gluconate-impregnated wipes failed to prevent SSTI; however, study adherence was moderate. Adherence with the study regimen (defined as use of ≥50% of the wipes) was 65% at week 2 and declined to 49% by week 6. Adherence was ~59% in the first two classes and declined in later classes. One-third felt that use of the wipes was disruptive. Participants were knowledgeable about MRSA SSTI prevention measures. However, only 53% agreed that MRSA commonly causes skin infections in military training facilities. Understanding adherence and its determinants is needed to optimize prevention strategies that require self-administration. Future efforts should address barriers to adherence with prevention strategies in recruit training settings.

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 ...

INTRODUCTION: Skin and soft-tissue infections (SSTIs) are an important cause of infectious disease morbidity among military populations. Due to the high direct and indirect costs associated with SSTIs, particularly with methicillin-resistant Staphylococcus aureus (MRSA) infections, there remains a critical need for the development and evaluation of SSTI prevention strategies among high-risk military personnel. Herein, we review efforts of the Infectious Disease Clinical Research Program (IDCRP) related to the prevention of SSTIs in the military. METHODS: The IDCRP of the Uniformed Services University has conducted clinical research protocols on SSTI epidemiology and prevention among military personnel since 2009. Observational studies have examined the epidemiology of Staphylococcus aureus colonization and SSTI in training and deployment settings. Two randomized controlled trials of personal hygiene strategies for SSTI prevention at Marine Corps Base Quantico (Virginia) and Fort Benning (Georgia) were performed. Lastly, two vaccine trials have been conducted by the IDCRP, including a Phase 2 S. aureus vaccine trial (currently ongoing) among military trainees. RESULTS: Military recruits and deployed personnel experience an intense and prolonged exposure to S. aureus, the major causative agent of SSTI. The burden of S. aureus colonization and SSTI is particularly high in military trainees. Hygiene-based trials for S. aureus decolonization among military trainees were not effective in reducing rates of SSTI. In January 2018, the IDCRP initiated a Phase 2 S. aureus vaccine trial among the US Army Infantry training population at Fort Benning. CONCLUSIONS: In the military, a disproportionate burden of SSTIs is borne by the recruit population. Strategies relying upon routine application of agents for S. aureus decolonization have not been effective in preventing SSTIs. A novel S. aureus vaccine candidate is being currently evaluated in a military training population and may represent a new opportunity to prevent SSTIs ...

Military personnel in congregate settings are at increased risk for acute gastroenteritis.1,2 Personal hygiene (eg, frequent hand washing, hand sanitizers, etc.) remains a central strategy. A skin and soft tissue infection (SSTI) prevention trial was conducted among military trainees.3 Trainees were randomized to 1 of 3 groups with incrementally increasing education- and hygiene-based measures. The principal components were promotion of hand washing in addition to a once-weekly application of a chlorhexidine-based body wash. Herein, we report the trial's impact on acute gastroenteritis.

In this prospective cluster-randomized trial among high-risk military trainees, personal hygiene and education measures, including once-weekly use of chlorhexidine body wash, did not prevent overall skin and soft tissue infection (SSTI) or methicillin-resistant Staphylococcus aureus SSTI.

Whole genome sequencing of Methicillin-Resistant Staphylococcus aureus (MRSA) from military trainees with skin and soft tissue infection revealed patterns of intra- and interclass disease transmission. A phylogenetic cluster stemming from 2 training classes separated by 1 year suggested a long-term reservoir for MRSA

The impact of HIV on influenza-like illness (ILI) has been incompletely described in the era of combination antiretroviral therapy, particularly in the post-H1N1 pandemic period. This analysis informs on ILI in an otherwise healthy, predominantly outpatient cohort of adults with HIV in the USA. From September 2010 to March 2015, this multisite observational cohort study enrolled otherwise healthy adults presenting to a participating US military medical center with ILI, a subset of whom were HIV positive. Demographics, clinical data, and self-reported symptom severity were ascertained, and enrollees completed a daily symptom diary for up to 10 days. 510 men were included in the analysis; 50 (9.8%) were HIV positive. Subjects with HIV were older and less likely to be on active duty. Rhinovirus and influenza A were the most commonly identified pathogens. Moderate–severe diarrhea (p<0.001) and fatigue (p=0.01) were more frequently reported by HIV-positive men. HIV positivity was associated with higher gastrointestinal scores, but not other measures of ILI symptom severity, after controlling for age, race, military status, and influenza season. Few were hospitalized. HIV-positive subjects had more influenza B (p=0.04) and were more likely to receive antivirals (32% vs 6%, p<0.01). Antiviral use was not significantly associated with symptom scores when accounting for potential confounders. In this predominantly outpatient cohort of adult men, HIV had minimal impact on ILI symptom severity. Despite similar illness severity, a higher percentage of subjects with HIV reported undergoing antiviral treatment for ILI, likely reflecting differences in prescribing practices.Trial registration number: NCT01021098.

Staphylococcus aureus is the leading cause of skin and soft tissue infections (SSTI). Some S. aureus strains harbor plasmids that carry genes that affect resistance to biocides. Among these genes, qacA encodes the QacA Multidrug Efflux Pump that imparts decreased susceptibility to chlorhexidine, a biocide used ubiquitously in healthcare facilities. Furthermore, chlorhexidine has been considered as a S. aureus decolonization strategy in community settings. We previously conducted a chlorhexidine-based SSTI prevention trial among Ft. Benning Army trainees. Analysis of a clinical isolate (C02) from that trial identified a novel qacA-positive plasmid, pC02. Prior characterization of qacA-containing plasmids is limited and conjugative transfer of those plasmids has not been demonstrated. Given the implications of increased biocide resistance, herein we characterized pC02. In silico analysis identified genes typically associated with conjugative plasmids. Moreover, pC02 was efficiently transferred to numerous S. aureus strains and to Staphylococcus epidermidis. We screened additional qacA-positive S. aureus clinical isolates and pC02 was present in 27% of those strains; other unique qacA-harboring plasmids were also identified. Ten strains were subjected to whole genome sequencing. Sequence analysis combined with plasmid screening studies suggest that qacA-containing strains are transmitted among military personnel at Ft. Benning and that strains carrying qacA are associated with SSTIs within this population. The identification of a novel mechanism of qacA conjugative transfer among Staphylococcal strains suggests a possible future increase in the prevalence of antiseptic tolerant bacterial strains, and an increase in the rate of infections in settings where these agents are commonly used.

In 2008, a clinical practice guideline (CPG) was developed for the prevention of infections among military personnel with combat-related injuries. Our analysis expands on a prior 6-month evaluation and assesses CPG adherence with respect to antimicrobial prophylaxis for U.S. combat casualties medically evacuated to Landstuhl Regional Medical Center over a 1-year period (June 2009 through May 2010), with an eventual goal of continuously monitoring CPG adherence and measuring outcomes as a function of compliance. We classified adherence to the CPG as receipt of recommended antimicrobials within 48 hours of injury. A total of 1106 military personnel eligible for CPG assessment were identified and 74% received antimicrobial prophylaxis. Overall, CPG compliance within 48 hours of injury was 75%. Lack of antimicrobial prophylaxis contributed 2 to 22% to noncompliance varying by injury category, whereas receipt of antibiotics other than preferred was 11 to 30%. For extremity injuries, antimicrobial prophylaxis adherence was 60 to 83%, whereas it was 80% for closed injuries and 68% for penetrating abdominal injuries. Overall, the results of our analysis suggest an ongoing need to improve adherence, monitor CPG compliance, and assess effectiveness.

Background: An outbreak of invasive fungal infections (IFI) began in 2009 among United States servicemen who sustained blast injuries in Afghanistan. In response, the military trauma community sought a uniform approach to early diagnosis and treatment. Toward this goal, a local clinical practice guideline (CPG) was implemented at Landstuhl Regional Medical Center (LRMC) in early 2011 to screen for IFI in high-risk patients using tissue histopathology and fungal cultures.

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.