Comparison of A(H3N2) Neutralizing Antibody Responses Elicited by 2018-2019 Season Quadrivalent Influenza Vaccines Derived from Eggs, Cells, and Recombinant Hemagglutinin.

BACKGROUND: Low vaccine effectiveness against A(H3N2) influenza in seasons with little antigenic drift has been attributed to substitutions in hemagglutinin (HA) acquired during vaccine virus propagation in eggs. Clinical trials comparing recombinant HA vaccine (rHA) and cell-derived inactivated influenza vaccine (IIV) to egg-derived IIVs provide opportunities to assess how egg-adaptive substitutions influence HA immunogenicity. METHODS: Neutralization titers in pre- and postimmunization sera from 133 adults immunized with 1 of 3 types of influenza vaccines in a randomized, open-label trial during the 2018-2019 influenza season were measured against egg- and cell-derived A/Singapore/INFIMH-16-0019/2016-like and circulating A(H3N2) influenza viruses using HA pseudoviruses. RESULTS: All vaccines elicited neutralizing antibodies to all H3 vaccine antigens, but the rHA vaccine elicited the highest titers and seroconversion rates against all strains tested. Egg- and cell-derived IIVs elicited responses similar to each other. Preimmunization titers against H3 HA pseudoviruses containing egg-adaptive substitutions T160K and L194P were high, but lower against H3 HA pseudoviruses without those substitutions. All vaccines boosted neutralization titers against HA pseudoviruses with egg-adaptive substitutions, but poorly neutralized wild-type 2019-2020 A/Kansas/14/2017 (H3N2) HA pseudoviruses. CONCLUSION: Egg- and cell-derived 2018-2019 season influenza vaccines elicited similar neutralization titers and response rates, indicating that the cell-derived vaccine did not improve immunogenicity against the A(H3N2) viruses. The higher responses after rHA vaccination may be due to its higher HA content. All vaccines boosted titers to HA with egg-adaptive substitutions, suggesting boosting from past antigens or better exposure of HA epitopes. Studies comparing immunogenicity and effectiveness of different influenza vaccines across many seasons are needed.

Chymase Level Is a Predictive Biomarker of Dengue Hemorrhagic Fever in Pediatric and Adult Patients.

Background: Most patients with dengue experience mild disease, dengue fever (DF), while few develop the life-threatening diseases dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). No laboratory tests predict DHF or DSS. We evaluated whether the serum chymase level can predict DHF or DSS in adult and pediatric patients and the influence of preexisting conditions (PECs) on chymase levels. Methods: Serum chymase levels were measured in patients presenting with undifferentiated fever to hospitals in Colombo District, Sri Lanka. The value of serum the chymase concentration and clinical signs and symptoms as predictors of DHF and/or DSS was evaluated by multivariate analysis. We assessed the influence of age, PECs, and day after fever onset on the robustness of the chymase level as a biomarker for DHF and/or DSS. Results: An elevated chymase level in acute phase blood samples was highly indicative of later diagnosis of DHF or DSS for pediatric and adult patients with dengue. No recorded PECs prevented an increase in the chymase level during DHF. However, certain PECs (obesity and cardiac or lung-associated diseases) resulted in a concomitant increase in chymase levels among adult patients with DHF. Conclusions: These results show that patients with acute dengue who present with high levels of serum chymase consistently are at greater risk of DHF. The chymase level is a robust prognostic biomarker of severe dengue for adult and pediatric patients.

Impact of Mucorales and Other Invasive Molds on Clinical Outcomes of Polymicrobial Traumatic Wound Infections.

Combat trauma wounds with invasive fungal infections (IFIs) are often polymicrobial with fungal and bacterial growth, but the impact of the wound microbiology on clinical outcomes is uncertain. Our objectives were to compare the microbiological features between IFI and non-IFI wounds and evaluate whether clinical outcomes differed among IFI wounds based upon mold type. Data from U.S. military personnel injured in Afghanistan with IFI wounds were examined. Controls were matched by the pattern/severity of injury, including blood transfusion requirements. Wound closure timing was compared between IFI and non-IFI control wounds (with/without bacterial infections). IFI wound closure was also assessed according to mold species isolation. Eighty-two IFI wounds and 136 non-IFI wounds (63 with skin and soft tissue infections [SSTIs] and 73 without) were examined. The time to wound closure was longer for the IFI wounds (median, 16 days) than for the non-IFI controls with/without SSTIs (medians, 12 and 9 days, respectively; P < 0.001). The growth of multidrug-resistant Gram-negative rods was reported among 35% and 41% of the IFI and non-IFI wounds with SSTIs, respectively. Among the IFI wounds, times to wound closure were significantly longer for wounds with Mucorales growth than for wounds with non-Mucorales growth (median, 17 days versus 13 days; P < 0.01). When wounds with Mucorales and Aspergillus spp. growth were compared, there was no significant difference in wound closure timing. Trauma wounds with SSTIs were often polymicrobial, yet the presence of invasive molds (predominant types: order Mucorales, Aspergillus spp., and Fusarium spp.) significantly prolonged the time to wound closure. Overall, the times to wound closure were longest for the IFI wounds with Mucorales growth.

Combat-Related Invasive Fungal Wound Infections.

INTRODUCTION: During Operation Enduring Freedom in Afghanistan, an outbreak of combat-related invasive fungal wound infections (IFIs) emerged among casualties with dismounted blast trauma and became a priority issue for the Military Health System. METHODS: In 2011, the Trauma Infectious Disease Outcomes Study (TIDOS) team led the Department of Defense IFI outbreak investigation to describe characteristics of IFIs among combat casualties and provide recommendations related to management of the disease. To support the outbreak investigation, existing IFI definitions and classifications utilized for immunocompromised patients were modified for use in epidemiologic research in a trauma population. Following the conclusion of the outbreak investigation, multiple retrospective analyses using a population of 77 IFI patients (injured during June 2009 to August 2011) were conducted to evaluate IFI epidemiology, wound microbiology, and diagnostics to support refinement of Joint Trauma System (JTS) clinical practice guidelines. Following cessation of combat operations in Afghanistan, the TIDOS database was comprehensively reviewed to identify patients with laboratory evidence of a fungal infection and refine the IFI classification scheme to incorporate timing of laboratory fungal evidence and include categories that denote a high or low level of suspicion for IFI. The refined IFI classification scheme was utilized in a large-scale epidemiologic assessment of casualties injured over a 5.5-year period. RESULTS: Among 720 combat casualties admitted to participating hospitals (2009-2014) who had histopathology and/or wound cultures collected, 94 (13%) met criteria for an IFI and 61 (8%) were classified as high suspicion of IFI. Risk factors for development of combat-related IFIs include sustaining a dismounted blast injury, experiencing a traumatic transfemoral amputation, and requiring resuscitation with large-volume (>20 units) blood transfusions. Moreover, TIDOS analyses demonstrated the adverse impact of IFIs on wound healing, particularly with order Mucorales. A polymerase chain reaction (PCR)-based assay to identify filamentous fungi and support earlier IFI diagnosis was also assessed using archived formalin-fixed, paraffin-embedded tissue specimens. Although the PCR-based assay had high specificity (99%), there was low sensitivity (63%); however, sensitivity improved to 83% in tissues collected from sites with angioinvasion. Data obtained from the initial IFI outbreak investigation (37 IFI patients) and subsequent TIDOS analyses (77 IFI patients) supported development and refinement of a JTS clinical practice guideline for the management of IFIs in war wounds. Furthermore, a local clinical practice guideline to screen for early tissue-based evidence of IFIs among blast casualties at the Landstuhl Regional Medical Center was critically evaluated through a TIDOS investigation, providing additional clinical practice support. Through a collaboration with the Uniformed Services University Surgical Critical Care Initiative, findings from TIDOS analyses were used to support development of a clinical decision support tool to facilitate early risk stratification. CONCLUSIONS: Combat-related IFIs are a highly morbid complication following severe blast trauma and remain a threat for future modern warfare. Our findings have supported JTS clinical recommendations, refined IFI classification, and confirmed the utility of PCR-based assays as a complement to histopathology and/or culture to promote early diagnosis. Analyses underway or planned will add to the knowledge base of IFI epidemiology, diagnostics, prevention, and management.

SARS-CoV-2 Infections and Serologic Responses Among Military Personnel Deployed on the USNS COMFORT to New York City During the COVID-19 Pandemic.

BACKGROUND: Coronavirus disease 2019 (COVID-19) presents a unique challenge to United States Navy hospital ships. The aim of this study was to determine the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among US Navy personnel deployed on the USNS COMFORT to augment the inpatient health care capacity in New York City. METHODS: This was a cross-sectional study conducted on USNS COMFORT crewmembers returning to Norfolk, Virginia, following deployment. Participants completed an electronic questionnaire and provided a serum sample at Day 14 post-deployment. Polymerase chain reaction (PCR) results from testing of symptomatic crewmembers during deployment and Day 0 and Day 14 post-deployment screening swabs conducted on all crewmembers, per military order, were abstracted. SARS-CoV-2 infection was defined as a positive SARS-CoV-2 spike glycoprotein immunoglobulin G antibody or PCR result. RESULTS: Of the ship's total complement of 1200 crewmembers, 450 were enrolled: 432 (96.0%) completed the questionnaire and provided a serum sample. The median age of participants (interquartile range) was 30 (24-39) years, 50.8% were female, 58.6% were White, and 14.0% were Black; 80.1% had a clinical role during deployment. The cumulative prevalence of SARS-CoV-2 infection was 3.01% (13/432; 95% CI, 1.61%-5.09%). Twelve of 13 infections occurred in health care providers, and 8 of 13 were asymptomatic. The antibody profile of infected crewmembers varied by suspected timing of infection. CONCLUSIONS: We observed a low prevalence of SARS-CoV-2 infection among USNS COMFORT crewmembers despite the inherent risk of a shipboard deployment to an area with high rates of community transmission. Our findings suggest that early infection control measures mitigated the spread of SARS-CoV-2 among crewmembers.

Bacteroides Fragilis Vertebral Osteomyelitis and Discitis: "Back" to Susceptibility Testing.

Genetic testing of anaerobic isolates can be important for proper antimicrobial stewardship to identify the appropriate narrow-spectrum treatment for a polymicrobial infection.

Virus detections among patients with severe acute respiratory illness, Northern Vietnam.

Severe acute respiratory illness (SARI) is a major cause of death and morbidity in low- and middle-income countries, however, the etiologic agents are often undetermined due to the lack of molecular diagnostics in hospitals and clinics. To examine evidence for select viral infections among patients with SARI in northern Vietnam, we studied 348 nasopharyngeal samples from military and civilian patients admitted to 4 hospitals in the greater Hanoi area from 2017-2019. Initial screening for human respiratory viral pathogens was performed in Hanoi, Vietnam at the National Institute of Hygiene and Epidemiology (NIHE) or the Military Institute of Preventative Medicine (MIPM), and an aliquot was shipped to Duke-NUS Medical School in Singapore for validation. Patient demographics were recorded and used to epidemiologically describe the infections. Among military and civilian cases of SARI, 184 (52.9%) tested positive for one or more respiratory viruses. Influenza A virus was the most prevalent virus detected (64.7%), followed by influenza B virus (29.3%), enterovirus (3.8%), adenovirus (1.1%), and coronavirus (1.1%). Risk factor analyses demonstrated an increased risk of influenza A virus detection among military hospital patients (adjusted OR, 2.0; 95% CI, 1.2-3.2), and an increased risk of influenza B virus detection among patients enrolled in year 2017 (adjusted OR, 7.9; 95% CI, 2.7-22.9). As influenza A and B viruses were commonly associated with SARI and are treatable, SARI patients entering these hospitals would benefit if the hospitals were able to adapt onsite molecular diagnostics.

Osteomyelitis Risk Factors Related to Combat Trauma Open Upper Extremity Fractures: A Case-Control Analysis.

OBJECTIVE: To determine risk factors for osteomyelitis in US military personnel with combat-related, extremity long bone (humerus, radius, and ulna) open fractures. DESIGN: Retrospective observational case-control study. SETTING: US military regional hospital in Germany and tertiary care military hospitals in the United States (2003-2009). PATIENTS/PARTICIPANTS: Sixty-four patients with open upper extremity fractures who met diagnostic osteomyelitis criteria (medical record review verification) were classified as cases. Ninety-six patients with open upper extremity fractures who did not meet osteomyelitis diagnostic criteria were included as controls. INTERVENTION: Not applicable. MAIN OUTCOME MEASUREMENTS: Multivariable odds ratios (ORs; 95% confidence interval [CI]). RESULTS: Among patients with surgical implants, osteomyelitis cases had longer time to definitive orthopaedic surgery compared with controls (median: 26 vs. 11 days; P < 0.001); however, there was no significant difference with timing of radiographic union. Being injured between 2003 and 2006, use of antibiotic beads, Gustilo-Anderson [GA] fracture classification (highest with GA-IIIb: [OR: 22.20; CI: 3.60-136.95]), and Orthopaedic Trauma Association Open Fracture Classification skin variable (highest with extensive degloving [OR: 15.61; CI: 3.25-74.86]) were independently associated with osteomyelitis risk. Initial stabilization occurring outside of the combat zone was associated with reduced risk of osteomyelitis. CONCLUSIONS: Open upper extremity fractures with severe soft-tissue damage have the highest risk of developing osteomyelitis. The associations with injuries sustained 2003-2006 and location of initial stabilization are likely from evolving trauma system recommendations and practice patterns during the timeframe. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

High Prevalence of Viral Infections Among Hospitalized Pneumonia Patients in Equatorial Sarawak, Malaysia.

BACKGROUND: Although pneumonia is a known cause of morbidity and mortality in Sarawak, Malaysia, the etiology and epidemiology of pneumonia are not well described in this equatorial region. Routine clinical diagnostics for pneumonia etiology at government hospitals in Sarawak had historically involved only bacterial diagnostics. Viral diagnostics were only obtained through outside consultations. METHODS: From June 15, 2017 to May 14, 2018, we collected nasopharyngeal swabs from 600 patients of all ages older than 1 month hospitalized with pneumonia at Sibu and Kapit Hospitals. Specimens were examined at our collaborating institutions with a panel of molecular assays for viral pathogens including influenza A (IAV), IBV, ICV, and IDV, human adenovirus (AdV), human enterovirus (EV), human coronavirus (CoV), respiratory syncytial virus subtype A (RSV-A) or RSV-B, and parainfluenza virus (PIV) types 1-4. RESULTS: Of 599 samples examined, 288 (48%) had molecular evidence of 1 or more respiratory viruses. Overall, the most prevalent virus detected was RSV-A (14.2%) followed by AdV (10.4%) and IAV (10.4%), then RSV-B (6.2%), EV (4.2%), IBV (2.2%), PIV-3 (1.7%), CoV (1.0%), PIV-1 (1.0%), PIV-4 (0.7%), and PIV-2 (0.2%). No specimens were confirmed positive for ICV or IDV. CONCLUSIONS: The high prevalence of viruses detected in this study suggest that respiratory viruses may be responsible for considerable morbidity in equatorial regions such as Sarawak. Access to viral diagnostics are very necessary for medical staff to determine appropriate pneumonia treatments.

Early Infections Complicating the Care of Combat Casualties from Iraq and Afghanistan.

BACKGROUND: During the conflicts in Iraq and Afghanistan, more than 52,000 U.S. military members were wounded in action. The battlefield mortality rate was lower than in past conflicts, however, those surviving often had complex soft tissue and bone injuries requiring multiple surgeries. This report describes the rates, types, and risks of infections complicating the care of combat casualties. PATIENTS AND METHODS: Infection and microbiology data obtained from the Trauma Infectious Disease Outcomes Study (TIDOS), a prospective observational study of infections complicating deployment-related injuries, were used to determine the proportion of infection, types, and associated organisms. Injury and surgical information were collected from the Department of Defense Trauma Registry. Multivariable Cox proportional hazards and logistic regression models were used to evaluate potential factors associated with infection. RESULTS: From 2009-2012, 1,807 combat casualties were evacuated to U.S. TIDOS-participating hospitals. Among the 1,807 patients, the proportion of overall infections from time of injury through initial U.S. hospitalization was 34% with half being skin, soft tissue, or bone infections. Infected wounds most commonly grew Enterococcus faecium, Pseudomonas aeruginosa, Acinetobacter spp. or Escherichia coli. In the multivariable model, amputation, blood transfusions, intensive care unit admission, injury severity scores, mechanical ventilation, and mechanism of injury were associated with risk of infection. CONCLUSIONS: One-third of combat casualties from Iraq and Afghanistan develop infections during their initial hospitalization. Amputations, blood transfusions, and overall injury severity are associated with risk of infection, whereas more easily modifiable factors such as early operative intervention or antibiotic administration are not.

Surveillance for respiratory syncytial virus and parainfluenza virus among patients hospitalized with pneumonia in Sarawak, Malaysia.

BACKGROUND: Respiratory syncytial virus (RSV) and parainfluenza virus (PIV) are frequent causes of pneumonia and death among children at Sibu and Kapit Hospitals in Sarawak, Malaysia. OBJECTIVES: To determine the prevalence and risk factors for RSV subtypes A and B and PIV types 1-4 among patients hospitalized with pneumonia. METHODS: In a cross-sectional, pilot study nasopharyngeal swabs were studied with real-time reverse transcription polymerase chain reaction assays. Concurrently, we helped Sibu and Kapit Hospitals adapt their first molecular diagnostics for RSV and PIV. RESULTS: Of 129 specimens collected (June to July 2017), 39 tested positive for RSV-A (30.2%), two were positive for RSV B (1.6%), one was positive for PIV-3 (0.8%) and one was positive for PIV-4 (0.8%). No samples were positive for PIV-1 or PIV-2. Of the 39 RSV-A positive specimens, 46.2% were collected from children under one year of age and only 5.1% were from patients over the age of 18. A multivariable analysis found the odds of children <1 year of age testing positive for RSV-A were 32.7 (95% CI: 3.9, 276.2) times larger than >18 years of age, and the odds of patients hospitalized at Kapit Hospital testing positive for RSV-A were 3.2 (95% CI: 1.3, 7.8) times larger than patients hospitalized at Sibu Hospital. CONCLUSION: This study found an unusually high prevalence of RSV-A among pneumonia patients admitted to the two hospitals. Subsequently, Sibu Hospital adapted the molecular assays with the goal of providing more directed care for such pneumonia patients.

Epidemiology of Trauma-Related Infections among a Combat Casualty Cohort after Initial Hospitalization: The Trauma Infectious Disease Outcomes Study.

BACKGROUND: The Trauma Infectious Disease Outcomes Study (TIDOS) cohort follows military personnel with deployment-related injuries in order to evaluate short- and long-term infectious complications. High rates of infectious complications have been observed in more than 30% of injured patients during initial hospitalization. We present data on infectious complications related to combat trauma after the initial period of hospitalization. PATIENTS AND METHODS: Data related to patient care for military personnel injured during combat operations between June 2009 and May 2012 were collected. Follow-up data were captured from interviews with enrolled participants and review of electronic medical records. RESULTS: Among 1,006 patients enrolled in the TIDOS cohort with follow-up data, 357 (35%) were diagnosed with one or more infection during their initial hospitalization, of whom 160 (45%) developed a trauma-related infection during follow-up (4.2 infections per 10,000 person-days). Patients with three or more infections during the initial hospitalization had a significantly higher rate of infections during the follow-up period compared with those with only one inpatient infection (incidence rate: 6.6 versus 3.1 per 10,000 days; p < 0.0001). There were 657 enrollees who did not have an infection during initial hospitalization, of whom 158 (24%) developed one during follow-up (incidence rate: 1.6 per 10,000 days). Overall, 318 (32%) enrolled patients developed an infection after hospital discharge (562 unique infections) with skin and soft-tissue infections being predominant (66%) followed by osteomyelitis (16%). Sustaining an amputation or open fracture, having an inpatient infection, and use of anti-pseudomonal penicillin (≥7 d) were independently associated with risk of an extremity wound infection during follow-up, whereas shorter hospitalization (15-30 d) was associated with a reduced risk. CONCLUSIONS: Combat-injured patients have a high burden of infectious complications that continue long after the initial period of hospitalization with soft-tissue and osteomyelitis being predominant. Further research on the long-term impact and outcomes of combat-associated infection is needed.

Impact of Operational Theater on Combat and Noncombat Trauma-Related Infections.

The Trauma Infectious Disease Outcomes Study began in June 2009 as combat operations were decreasing in Iraq and increasing in Afghanistan. Our analysis examines the rate of infections of wounded U.S. military personnel from operational theaters in Iraq and Afghanistan admitted to Landstuhl Regional Medical Center between June 2009 and December 2013 and transferred to a participating U.S. hospital. Infection risk factors were examined in a multivariate logistic regression analysis (expressed as odds ratios [OR]; 95% confidence intervals [CI]). The study population includes 524 wounded military personnel from Iraq and 4,766 from Afghanistan. The proportion of patients with at least one infection was 28% and 34% from the Iraq and Afghanistan theaters, respectively. The incidence density rate was 2.0 (per 100 person-days) for Iraq and 2.7 infections for Afghanistan. Independent risk factors included large-volume blood product transfusions (OR: 10.68; CI: 6.73-16.95), high Injury Severity Score (OR: 2.48; CI: 1.81-3.41), and improvised explosive device injury mechanism (OR: 1.84; CI: 1.35-2.49). Operational theater (OR: 1.32; CI: 0.87-1.99) was not a risk factor. The difference in infection rates between operational theaters is primarily a result of increased injury severity in Afghanistan from a higher proportion of blast-related trauma during the study period.

Compliance with antimalarial chemoprophylaxis recommendations for wounded United States military personnel admitted to a military treatment facility.

Malaria chemoprophylaxis is used as a preventive measure in military personnel deployed to malaria-endemic countries. However, limited information is available on compliance with chemoprophylaxis among trauma patients during hospitalization and after discharge. Therefore, we assessed antimalarial primary chemoprophylaxis and presumptive antirelapse therapy (primaquine) compliance among wounded United States military personnel after medical evacuation from Afghanistan (June 2009-August 2011) to Landstuhl Regional Medical Center in Landstuhl, Germany, and then to three U.S. military hospitals. Among admissions at Landstuhl Regional Medical Center, 74% of 2,540 patients were prescribed primary chemoprophylaxis and < 1% were prescribed primaquine. After transfer of 1,331 patients to U.S. hospitals, 93% received primary chemoprophylaxis and 33% received primaquine. Of 751 trauma patients with available post-admission data, 42% received primary chemoprophylaxis for four weeks, 33% received primaquine for 14 days, and 17% received both. These antimalarial chemoprophylaxis prescription rates suggest that improved protocols to continue malaria chemoprophylaxis in accordance with force protection guidelines are needed.

Risk factors associated with invasive fungal infections in combat trauma.

BACKGROUND: In recent years, invasive fungal infections (IFI) have complicated the clinical course of patients with combat-related injuries. Commonalities in injury patterns and characteristics among patients with IFI led to the development of a Joint Trauma System (JTS) clinical practice guideline (CPG) for IFI management. We performed a case-control study to confirm and further delineate risk factors associated with IFI development in combat casualties with the objective of generating data to refine the CPG and promote timelier initiation of treatment. METHODS: Data were collected retrospectively for United States (U.S.) military personnel injured during deployment in Afghanistan from June 2009 through August 2011. Cases were identified as IFI based upon wound cultures with fungal growth and/or fungal elements seen on histology, in addition to the presence of recurrent wound necrosis. Controls were matched using date of injury (±3 mo) and injury severity score (±10). Risk factor parameters analyzed included injury circumstances, blood transfusion requirements, amputations after first operative intervention, and associated injuries. Data are expressed as multivariate odds ratios (OR; 95% confidence interval [CI]). RESULTS: Seventy-six IFI cases were identified from 1,133 U.S. military personnel wounded in Afghanistan and matched to 150 controls. Parameters associated significantly with the development of IFI multivariate analysis were blast injuries (OR: 5.7; CI: 1.1-29.6), dismounted at time of injury (OR: 8.5; CI: 1.2-59.8); above the knee amputations (OR: 4.1; CI: 1.3-12.7), and large-volume packed red blood cell (PRBC; >20 U) transfusions within first 24 h (OR: 7.0; CI: 2.5-19.7). CONCLUSIONS: Our analysis indicates that dismounted blast injuries, resulting in above the knee amputations, and requirement of large volume PRBC transfusions are independent predictors of IFI development. These data confirm all the preliminary risk factors, except for genitalia/perineal injuries, utilized by JTS in their IFI CPG. Model validation is necessary for further risk factor specification.