Safety of Bioplasma FDP and Hemopure in rhesus macaques after 30% hemorrhage.

Objectives: Prehospital transfusion can be life-saving when transport is delayed but conventional plasma, red cells, and whole blood are often unavailable out of hospital. Shelf-stable products are needed as a temporary bridge to in-hospital transfusion. Bioplasma FDP (freeze-dried plasma) and Hemopure (hemoglobin-based oxygen carrier; HBOC) are products with potential for prehospital use. In vivo use of these products together has not been reported. This study assessed the safety of intravenous administration of HBOC+FDP, relative to normal saline (NS), in rhesus macaques (RM). Methods: After 30% blood volume removal and 30 minutes in shock, animals were resuscitated with either NS or two units (RM size adjusted) each of HBOC+FDP during 60 minutes. Sequential blood samples were collected. After neurological assessment, animals were killed at 24 hours and tissues collected for histopathology. Results: Due to a shortage of RM during the COVID-19 pandemic, the study was stopped after nine animals (HBOC+FDP, seven; NS, two). All animals displayed physiologic and tissue changes consistent with hemorrhagic shock and recovered normally. There was no pattern of cardiovascular, blood gas, metabolic, coagulation, histologic, or neurological changes suggestive of risk associated with HBOC+FDP. Conclusion: There was no evidence of harm associated with the combined use of Hemopure and Bioplasma FDP. No differences were noted between groups in safety-related cardiovascular, pulmonary, renal or other organ or metabolic parameters. Hemostasis and thrombosis-related parameters were consistent with expected responses to hemorrhagic shock and did not differ between groups. All animals survived normally with intact neurological function. Level of evidence: Not applicable.

Seroepidemiologic Investigation of a COVID-19 Outbreak Aboard a U.S. Navy Ship.

The crew of USS Kidd experienced a COVID-19 outbreak identified in April 2020. This is the earliest documented COVID-19 study with RT-PCR, serology, and pre-exposure test data on the entirety of the exposed population (n=333). Case definitions included 121 confirmed (36.3% of crewmembers) and 18 probable (5.4% of crewmembers) based on laboratory diagnostic test results. At the time of testing positive, 62 (44.6%) cases reported no symptoms. Hispanic ethnicity (AOR: 2.71, CI: 1.40-5.25) and non-smoker status (AOR: 2.28, CI: 1.26-4.12) were identified as statistically significant risk factors. This study highlights the value of rapid, onboard diagnostic testing to quickly identify an outbreak and enumerate cases, as well as the serological testing to flag potential cases missed with standard viral case identification methodologies.

Department of Defense mid-season vaccine effectiveness estimates for the 2019-2020 influenza season.

This report provides mid-season vaccine effectiveness (VE) estimates from the Armed Forces Health Surveillance Division (AFHSD), the DoD Global Respiratory Pathogen Surveillance (DoDGRS) program, and the Naval Health Research Center (NHRC) for the 2019-2020 influenza season. Using a test negative case-control study design, the AFHSD performed a VE analysis for active component service members while the DoDGRS program and NHRC collaborated to perform a VE analysis for DoD beneficiaries and U.S.-Mexico border civilians. Among active component service members, there was low to moderate protection against influenza B, moderate protection against A(H3N2), and non-statistically significant low protection against influenza A overall and A(H1N1). Among DoD beneficiaries and U.S.-Mexico border civilians, there was statistically significant moderate protection against influenza B, influenza A overall, A(H1N1), and A(H3N2).

Duration of seropositivity following yellow fever vaccination in U.S. military service members.

BACKGROUND: The United States military regularly deploys thousands of service members throughout areas of South America and Africa that are endemic for yellow fever (YF) virus. To determine if booster doses might be needed for service members who are repetitively or continually deployed to YF endemic areas, we evaluated seropositivity among US military personnel receiving a single dose of YF vaccine based on time post-vaccination. METHODS: Serum antibodies were measured using a plaque reduction neutralization test with 50% cutoff in 682 military personnel at 5-39 years post-vaccination. We determined noninferiority of immune response by comparing the proportion seropositive among those vaccinated 10-14 years previously with those vaccinated 5-9 years previously. Noninferiority was supported if the lower-bound of the 2-tailed 95% CI for p10-14years - p5-9years was ≥-0.10. Additionally, the geometric mean antibody titer (GMT) at various timepoints following vaccination were compared to the GMT at 5-9 years. RESULTS: The proportion of military service members with detectable neutralizing antibodies 10-14 years after a single dose of YF vaccine (95.8%, 95% CI 91.2-98.1%) was non-inferior to the proportion 5-9 years after vaccination (97.8%, 95% CI 93.7-99.3%). Additionally, GMT among vaccine recipients at 10-14 years post vaccination (99, 95% CI 82-121) was non-inferior to GMT in YF vaccine recipients at 5-9 years post vaccination (115, 95% CI 96-139). The proportion of vaccinees with neutralizing antibodies remained high, and non-inferior, among those vaccinated 15-19 years prior (98.5%, 95%CI 95.5-99.7%). Although the proportion seropositive decreased among vaccinees ≥ 20 years post vaccination, >90% remained seropositive. CONCLUSIONS: Neutralizing antibodies were present in > 95% of vaccine recipients for at least 19 years after vaccination, suggesting that booster doses every 10 years are not essential for most U.S. military personnel.

Immune response at 12-23 months following a single dose of Vero cell culture-derived Japanese encephalitis (JE) vaccine in adults previously vaccinated with mouse brain-derived JE vaccine.

BACKGROUND: Japanese encephalitis (JE) virus is an important cause of neurological disease in Asia. JE vaccine is recommended for travelers with higher JE risk itineraries. Inactivated Vero cell culture-derived JE vaccine (JE-VC) is the only JE vaccine currently available in the United States. An inactivated mouse brain-derived JE vaccine (JE-MB) previously was available but production was discontinued. One JE-VC dose administered to adults previously vaccinated with ≥3 doses of JE-MB provides good short-term protection for at least one month, but data on longer-term protection are limited. We evaluated non-inferiority of the JE virus neutralizing antibody response at 12-23 months in JE-MB-vaccinated adults administered one JE-VC dose compared with JE vaccine-naïve adults administered a JE-VC two-dose primary series. METHODS: We obtained archived sera from U.S. military personnel and performed a 50% plaque reduction neutralization test for anti-JE virus neutralizing antibodies. We compared the geometric mean titer (GMT) and seroprotection rate at 12-23 months after one JE-VC dose in previously JE-MB-vaccinated personnel and after the second JE-VC dose in previously JE vaccine-naïve personnel. Non-inferiority was concluded if the lower bound of the two-sided 95% confidence interval (CI) of the GMT ratio in previously vaccinated to vaccine-naïve personnel was >1/1.5. RESULTS: The GMT in previously JE-MB-vaccinated persons was 75 (95% CI 63-90) and in previously JE vaccine-naïve persons was 12 (95% CI 11-14), and seroprotection rates were 94% (235/250) and 54% (135/250), respectively. The ratio of GMTs was 6.3 (95% CI: 5.0-7.7), satisfying the criterion for non-inferiority. CONCLUSIONS: One JE-VC dose in previously JE-MB-vaccinated military personnel provides good protection for at least 1-2 years. The benefits of administration of a single JE-VC dose in previously JE-MB-vaccinated adults include a shorter time to completion of re-vaccination before travel, a decrease in the risk of adverse events, and reduced costs.