Characteristics, Treatment, and Outcomes of Patients With Severe or Life-threatening COVID-19 at a Military Treatment Facility-A Descriptive Cohort Study.

INTRODUCTION: The treatment of severe and life-threatening COVID-19 is a rapidly evolving practice. The purpose of our study was to describe the characteristics and outcomes of patients with severe or life-threatening COVID-19 who present to a Military Treatment Facility (MTF) with an emphasis on addressing institutional adaptations to rapidly changing medical evidence. MATERIALS AND METHODS: A single-center retrospective study conducted on a prospectively maintained cohort. The MTF is a 52-bed hospital within an urban setting. Patients were included in the cohort if they had laboratory-confirmed severe or life-threatening COVID-19 with positive SARS-CoV-2 reverse transcription polymerase chain reaction. Severe disease was defined as dyspnea, respiratory frequency ≥30/min, blood oxygen saturation ≤93% on ambient air, partial pressure of arterial oxygen to fraction of inspired oxygen ratio <300, or lung infiltrates involving >50% of lung fields within 24-48 hours. Life-threatening COVID-19 was defined as respiratory failure, septic shock, or multiple organ dysfunction. The cohort included patients admitted from June 1 through November 13. Data were collected retrospectively via chart review by a resident physician. RESULTS: In total, our MTF saw 14 cases of severe or life-threatening COVID-19 from June 1 to November 13. Patients had a median age of 70.5 years, with 7% being active duty personnel, 21% dependents, and 71% retired military members. The median time to dexamethasone, remdesivir, and convalescent plasma administration was 4.7, 6.3, and 11.2 hours, respectively. The 28-day in-hospital mortality was 0%. CONCLUSIONS: Patients who present to an MTF with severe or life-threatening COVID-19 are largely retirees, with only a small fraction comprising active duty personnel. The institution of order sets and early consultation can help facilitate prompt patient care for COVID-19.

Travel-associated multidrug-resistant organism acquisition and risk factors among US military personnel.

BACKGROUND: International travel is a risk factor for incident colonization with extended spectrum beta-lactamase (ESBL)-producing organisms. These and other multidrug-resistant (MDR) bacteria are major pathogens in combat casualties. We evaluated risk factors for colonization with MDR bacteria in US military personnel travelling internationally for official duty. METHODS: TravMil is a prospective observational study enrolling subjects presenting to military travel clinics. We analysed surveys, antimicrobial use data, and pre- and post-travel perirectal swabs in military travellers to regions outside the continental USA, Canada, Western or Northern Europe, or New Zealand, presenting to one clinic from 12/2015 to 12/2017. Recovered Gram-negative isolates underwent identification and susceptibility testing (BD Phoenix). Characteristics of trip and traveller were analysed to determine risk factors for MDR organism colonization. RESULTS: 110 trips were planned by 99 travellers (74% male, median age 38 years [IQR 31, 47.25]); 72 trips with returned pre- and post-travel swabs were completed by 64 travellers. Median duration was 21 days (IQR 12.75, 79.5). 17% travelled to Mexico/Caribbean/Central America, 15% to Asia, 57% to Africa and 10% to South America; 56% stayed in hotels and 50% in dormitories/barracks. Travellers used doxycycline (15%) for malaria prophylaxis, 11% took an antibiotic for travellers' diarrhoea (TD) treatment (fluoroquinolone 7%, azithromycin 4%). Incident MDR organism colonization occurred in 8 travellers (incidence density 3.5/1000 travel days; cumulative incidence 11% of trips [95% CI: 4-19%]), all ESBL-producing Escherichia coli. A higher incidence of ESBL-producing E. coli acquisition was associated with travel to Asia (36% vs 7%, P = 0.02) but not with travel to other regions, TD or use of antimicrobials. No relationship was seen between fluoroquinolone or doxycycline exposure and resistance to those antimicrobials. CONCLUSIONS: Incident colonization with MDR organisms occurs at a lower rate in this military population compared with civilian travellers, with no identified modifiable risk factors, with highest incidence of ESBL acquisition observed after South Asia travel.

Influenza virus subpopulations: exchange of lethal H5N1 virus NS for H1N1 virus NS triggers de novo generation of defective-interfering particles and enhances interferon-inducing particle efficiency.

Reassortment of influenza A viruses is known to affect viability, replication efficiency, antigenicity, host range, and virulence, and can generate pandemic strains. In this study, we demonstrated that the specific exchange of the NS gene segment from highly pathogenic A/HK/156/97 (H5N1) [E92 or E92D NS1] virus for the cognate NS gene segment of A/PR/834(H1N1) [D92 NS1] virus did not cause a significant change in the sizes of infectious particle subpopulations. However, it resulted in 2 new phenotypic changes: (1) de novo generation of large subpopulations of defective-interfering particles (DIPs); and (2) enhancement of interferon (IFN)-inducing particle efficiency leading to an order of magnitude or higher quantum (peak) yield of IFN in both avian and mammalian cells. These changes were attributed to loss of function of the H5N1-NS gene products. Most notably, the NS exchange obliterated the usual IFN-induction-suppressing capacity associated with expression of full-size NS1 proteins, and hence functionally mimicked deletions in the NS1 gene. The loss of NS1-mediated suppression of IFN induction, de novo generation of DIPs, and the concomitant enhancement of IFN-inducing particle efficiency suggest that in an attenuated background, the H5N1-NS could be used to formulate a self-adjuvanting live attenuated influenza vaccine similar to viruses with deletions in the NS1 gene.

Physical interaction between the herpes simplex virus type 1 exonuclease, UL12, and the DNA double-strand break-sensing MRN complex.

The herpes simplex virus type 1 (HSV-1) alkaline nuclease, encoded by the UL12 gene, plays an important role in HSV-1 replication, as a UL12 null mutant displays a severe growth defect. The HSV-1 alkaline exonuclease UL12 interacts with the viral single-stranded DNA binding protein ICP8 and promotes strand exchange in vitro in conjunction with ICP8. We proposed that UL12 and ICP8 form a two-subunit recombinase reminiscent of the phage lambda Red α/ß recombination system and that the viral and cellular recombinases contribute to viral genome replication through a homologous recombination-dependent DNA replication mechanism. To test this hypothesis, we identified cellular interaction partners of UL12 by using coimmunoprecipitation. We report for the first time a specific interaction between UL12 and components of the cellular MRN complex, an important factor in the ATM-mediated homologous recombination repair (HRR) pathway. This interaction is detected early during infection and does not require viral DNA or other viral or cellular proteins. The region of UL12 responsible for the interaction has been mapped to the first 125 residues, and coimmunoprecipitation can be abolished by deletion of residues 100 to 126. These observations support the hypothesis that cellular and viral recombination factors work together to promote efficient HSV-1 growth.