Seasonal outbreaks of acute respiratory infections (ARI) are a leading cause of morbidity in the Military Health System (MHS), particularly among military trainees and deployed service members. With approximately 400,000 medical encounters and 1,000 hospitalizations per year, ARIs not only affect the health of military personnel, but also greatly impact operational readiness through missed training and lost duty days.
Increased virulence of known respiratory pathogens, limited effectiveness of vaccines, diagnostic difficulties, and heightened potential for transmission from crowded, stressful living conditions are all factors contributing to the high prevalence of ARIs in service members. The goal of the ARI Research Area is to substantially reduce the burden of ARIs in military populations by generating evidence needed to inform the development of effective control strategies designed to limit the impact of ARIs on health, performance, and mission readiness.
IDCRP-045-01: Severity symptom grading scale for influenza infection (Flu-PRO) IDCRP-046: Pilot study for collection of anti-influenza A H1N1 (Swine flu) hyper-immune plasma IDCRP-058: Clinical characteristics of novel H1N1 influenza infection in US-based military treatment facilities: A one-year retrospective review IDCRP-062: A randomized, open-label, phase 2, multicenter safety and exploratory efficacy study of investigational anti-influenza A immune plasma for the treatment of influenza
IDCRP-070: Self-administered nasal influenza vaccine: immunogenicity and feasibility of group administration
IDCRP-081: Evaluation of Psychometric Testing Properties of Severity Symptom Grading Scale of Influenza Infection: Flu-Pro Stage III
COVID-10: http://www.idcrp.org/covid-19
Military Impact
In 2019, the DoD Infectious Disease Threat Prioritization Panel ranked influenza as the second-highest infectious disease threat to U.S. Armed Forces. Since inception, findings from ARI Research Area studies have advanced the understanding of the changing distribution, risk factors, and control of ARI in the MHS. Hospital-based surveillance efforts provide valuable data on ARI epidemiology, clinical severity, and disease burden for high-priority pathogens that may directly impact operational readiness. Furthermore, although there is widespread coverage of the influenza vaccine in the MHS, overall vaccine effectiveness varies from 19% in service members to 51% in DoD beneficiaries. Findings from PAVED and the Influenza Vaccine& Experience studies may provide insight to account for the disparities in vaccine effectiveness in military personnel and beneficiaries and support the next generation of influenza vaccinations and vaccine policies in the MHS. Furthermore, ARIs are a frequent occurrence in congregate military populations, such as trainees. Findings from ATARI and anonymous surveys related to transmission patterns and health care seeking behavior may inform educational interventions to reduce the risk of ARI transmission.
Highlights / Key Findings
- One out of every 6 non-recruit participants enrolled in PAIVED during the 2018/19 influenza season experienced a confirmed ILI with coronavirus (15%), rhinovirus (10%), and respiratory syncytial virus (8%) being most common. Symptoms lasted 6-8 days in duration with approximately 3-4 days of reduced activity.
- Among recruits at the Marine Corps Recruit Depot San Diego enrolled in PAIVED during the 2018/19 influenza season, 23% reported an ILI with influenza A(H3) being the most common. Approximately 82% of the ILIs were during the first 3 weeks of training, resulting in a total of 168 days of reduced training and 47 days of missed training.
- Findings from an anonymous survey of >2,400 trainees found that only 40% of trainees who experienced an ILI sought health care, indicating that ILIs are more common during training than what is indicated in medical records. Recruits who are male and over 30 years of age were less likely to seek health care for ILIs.
Partners and Collaborators
IDCRP collaborates with the National Institute of Allergy and Infectious Diseases (NIAID), Walter Reed Army Institute of Research (WRAIR), Naval Medical Research Center (NMRC), the Armed Forces Health Surveillance Branch (AFHSB) Global Emerging Infections Surveillance and Response System (GEIS) and partner military treatment facilities inside and outside the continental United States.