Navy Study Confirms Vaccine Effectiveness in Recruits

By Anna Hancock, Naval Health Research Center Public Affairs Officer

SAN DIEGO (NNS) -- A recent study led by the Naval Health Research Center (NHRC) in San Diego confirmed the effectiveness of the adenovirus vaccine after observing a 100-fold decline in respiratory illnesses in U.S. military recruits.

The study, published in Clinical Infectious Diseases (CID) this summer, examined the impact on Navy, Marine Corps, Air Force, Coast Guard, and Army recruits after the sole manufacturer ceased production for a 12-year period starting in 1996. Since the resumption of the vaccine in 2011, the study highlights the vaccine prevented an estimated three deaths and up to 8,100 hospitalizations within the military population.

"Febrile Respiratory Illnesses (FRI) resulting from adenovirus were responsible for an estimated $600 million in training time lost and medical expenses during the 12 years with no vaccines," explained Anthony Hawksworth, an analyst at NHRC and coauthor of the study. "Adenovirus, which causes flu-like symptoms and often leads to pneumonia, greatly impacted training during the nonvaccine period, disrupting training schedules and causing a significant number of recruits to drop out of the program."

Accounting for the cost of the vaccines, according to Hawksworth, NHRC estimates an annual savings of $20 million since vaccine resumption.

For a recruit, basic training or "boot camp" is a vigorous six- to 12- week training program. It teaches the fundamentals of military service and trainees undergo rigorous physical fitness programs. Adenovirus is the most prevalent and most widely spread virus in military training environments - with estimates of up to 80 percent of recruits infected - without adenovirus vaccines.

As Hawksworth noted, "administering the vaccine wasn't an option during this time because the manufacturer made a business decision to stop making it. The military took prevention measures such as increased hand washing and other environmental controls but literature shows, as does our study, that those methods are not nearly as effective as vaccination."

FRI surveillance for this study took place at eight military recruit training facilities across the U.S. from 1996 until 2013. When vaccine supplies ran out, experts saw the virus become highly endemic in recruit training centers. In 2001, the Army worked with pharmaceutical companies to resume production. NHRC then tested the vaccines with Army counterparts and it received FDA approval in 2011.

"After the military reinstated the vaccine, the average plummeted from about 250 cases of the virus each week to two," said Hawksworth.

NHRC regularly conducts disease surveillance around the world, including within San Diego-based military populations and at the U.S.-Mexico border in collaboration with the Centers for Disease Control and Prevention (CDC). Military health care officials at NHRC are required to report a weekly FRI update as part of the Armed Forces Health Surveillance Program, the global health surveillance proponent for epidemiology across the Department of Defense.

"This is a study that can easily be translatable to the civilian sector," explained Cmdr. Gary Brice, NHRCs director for the Operational Infectious Diseases Directorate. "Our results reinforce the message that FDA-approved vaccines are safe and very effective. For our military service members, protecting them is our primary mission."

As the DoD's premier deployment health research center, NHRCs cutting-edge research and development is used to optimize the operational health and readiness of the nation's armed forces. Within close proximity to more than 95,000 uniformed service members, world-class universities, and industry partners, NHRCs expert team sets the standards in joint ventures, innovation, and practical application.