Surveillance outcomes of respiratory pathogen infections during the 2021-2022 season among U.S. Military Health System beneficiaries, October 3, 2021-October 1, 2022.

The Department of Defense Global Respiratory Pathogen Surveillance Program conducts continuous surveillance for influenza, severe acute respiratory syndrome 2 (SARS-CoV-2), and other respiratory pathogens at 104 sentinel sites across the globe. These sites submitted 65,475 respiratory specimens for clinical diagnostic testing during the 2021-2022 surveillance season. The predominant influenza strain was influenza A(H3N2) (n=777), of which 99.9% of strains were in clade 3C.2a1b.2a2. A total of 21,466 SARSCoV-2-positive specimens were identified, and 12,225 of the associated viruses were successfully sequenced. The Delta variant predominated at the start of the season, until December 2021, when Omicron became dominant. Most circulating SARS-CoV-2 viruses were subsequently held by Omicron sublineages BA.1, BA.2, and BA.5 during the season. Clinical manifestation, obtained through a self-reported questionnaire, found that cough, sinus congestion, and runny nose complaints were the most common symptoms presenting among all pathogens. Sentinel surveillance can provide useful epidemiological data to supplement other disease monitoring activities, and has become increasingly useful with increasing numbers of individuals utilizing COVID-19 rapid self-test kits and reductions in outpatient visits for routine respiratory testing.

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).

Influenza Surveillance Trends and Influenza Vaccine Effectiveness Among Department of Defense Beneficiaries During the 2019-2020 Influenza Season.

Laboratory-based influenza surveillance was conducted in the 2019-2020 influenza season among Department of Defense (DoD) beneficiaries through the DoD Global Respiratory Pathogen Surveillance Program (DoDGRS). Sentinel and participating sites submitted 28,176 specimens for clinical diagnostic testing. A total of 5,529 influenza-positive cases were identified. Starting at surveillance week 45 (3-9 November 2019), influenza B was the predominant influenza type, followed by high activity of influenza A(H1N1)pdm09 three weeks thereafter. Both influenza B and influenza A(H1N1)pdm09 were then highly co-circulated through surveillance week 13 (22-28 March 2020). End-of-season influenza vaccine effectiveness (VE) was estimated using a test-negative case-control study design. The adjusted end-of-season VE for all beneficiaries, regardless of influenza type or subtype, was 46% (95% confidence interval: 40%-52%). The influenza vaccine was moderately effective against influenza viruses during the 2019-2020 influenza season.

The DoD Global, Laboratory-based, Influenza Surveillance Program: summary for the 2013-2014 influenza season.

This report for the 2013-2014 influenza season summarizes the results of influenza surveillance carried out by the DoD Global, Laboratory-based, Influenza Surveillance Program, which is managed by the U.S. Air Force School of Aerospace Medicine Epidemiology Consult Service and Epidemiology Laboratory at Wright-Patterson Air Force Base, OH. Sentinel sites submitted 3,903 specimens for clinical diagnostic testing and 1,163 (29.8%) were positive for influenza virus. The predominant influenza subtype was influenza A(H1N1)pdm09, identified in 79.2% of all influenza-positive specimens. The other most common subtypes were influenza A(H3N2) (10.5%) and influenza B (10.1%). In August 2014, a human case of influenza A(H3N2) variant was identified in a patient with a history of exposure to swine. Adjusted vaccine effectiveness (VE) was calculated among 1,016 military dependents and retirees in the U.S. and was found to be 44.8% for all vaccine types. Uncertainties and other limitations associated with estimating VE are discussed.

Pneumonia Outbreak Caused by Chlamydophila pneumoniae among US Air Force Academy Cadets, Colorado, USA.

During October 2013-May 2014, there were 102 cases of pneumonia diagnosed in US Air Force Academy cadets. A total of 73% of tested nasal washes contained Chlamydophila pneumoniae. This agent can be considered to be present on campus settings during outbreaks with numerous, seemingly disconnected cases of relatively mild pneumonia.