AFRL Influenza Surveillance aims to keep Airmen, civilians healthy

  • Published
  • By Derek Hardin
  • Air Force Research Laboratory
It's a well-known fact that the U.S. is deep into the flu season and millions of people across the country are contending with the high body temperatures, aches, and general malaise associated with the yearly disease. 

But it's probably less known that the Air Force Research Laboratory plays a huge role in the global monitoring and combat of influenza.  And it's all in effort to keep America's warfighters at the ready and the general population healthy and happy.

Since 1976, AFRL's U.S. Air Force School of Aerospace Medicine (USAFSAM) has been routinely conducting Laboratory-based influenza monitoring for the Department of Defense.  The DoD USAFSAM Global, Laboratory-based Influenza Surveillance Program has been located at Wright-Patterson Air Force Base since 2011 when USAFSAM transitioned to Ohio from Brooks City Base, in San Antonio.

Specimens were initially collected from neighboring Lackland Air Force Base, the home of Air Force Basic Military Training; then from 1977 - 1995, the program expanded globally.  In 1997, the Global Emerging Infections Surveillance and Response System (GEIS), established and began to support a global network to conduct laboratory-based respiratory surveillance.  This network consists nationally of the Epidemiology Laboratory at USAFSAM and the Naval Health Research Center in San Diego, California. In addition, GEIS is comprised of five international laboratories, located in Egypt, Cambodia, Thailand, Peru, and Kenya.

USAFSAM's influenza surveillance program tracks trends among active duty Airmen and their dependents, worldwide.  Respiratory illness, such as influenza, is a significant cause of troop morbidity which ultimately degrades troop readiness.  Influenza affects millions of civilians each year and is particularly threatening to infants, the elderly, and those with weakened immune systems.

"What some people are unaware of is how deadly influenza can be," said Shauna Zorich, a preventative medicine consultant with USAFSAM's Epidemiology Consult Service.  "A particularly deadly strain of influenza was responsible for the influenza pandemic of 1918.  This pandemic sickened 500 million people, and killed between 50-100 million people across the globe.  More people died from the 1918 influenza pandemic than during World War I."

Zorich's main charge is to coordinate USAFSAM's global influenza surveillance program.  She said that the program receives its data from over 90 remote, or sentinel, sites located throughout North America, Europe, the Middle East, and the Pacific.  Respiratory specimens are collected weekly from active duty members and dependents who visit medical treatment facilities at these sentinel sites with influenza-like illness, which includes a fever, cough, and/or sore throat.  Once the specimens reach USAFSAM, they are tested for influenza and other respiratory pathogens via viral culture and molecular techniques.  Many specimens that test positive for influenza also undergo molecular sequencing which allows USAFSAM to track genetic changes occurring in circulating influenza.

Data gathered at USAFSAM is shared weekly with the U.S. Centers for Disease Control and Prevention (CDC).  This data contributes to the overall data utilized by the CDC to produce their weekly national influenza reports.  Currently, the CDC is reporting that 46 states are experiencing high or widespread flu activity.
 
This season's predominant strain is influenza A(H3N2).  According to Zorich, to date, over 60 percent of influenza A(H3N2) stains tested are genetically distinguishable from the strain that was chosen for this season's vaccine.  Ultimately, what this means is the match between the influenza A(H3N2) that is circulating and the vaccine strain is not optimal and protection against the illness has been reduced. This is ultimately why the U.S. is experiencing such a heavy influx of influenza cases.

Despite this CDC officials still recommend vaccination.  The vaccine protects against three or four influenza viruses.  It is possible we will see these other viruses circulate later in the season, so vaccination is still important. Experts predict that we will continue to see influenza in the coming weeks and further increases are especially likely in states that have seen less activity to date.

USAFSAM is also responsible for the DoD combined molecular sequence analysis.  This data is also shared with the CDC who incorporates it with their own data who then presents it to the Food and Drug Administration's Vaccines and Related Biological Products Advisory Committee (VRBPAC).  This information is then utilized by the VRBPAC to assist in making the strain determinations for the following season's vaccine.

"The DoD Global, Laboratory-based Influenza Surveillance Program plays a very important role in  influenza surveillance, impacting not only the DoD, but the U.S. population," said Zorich.  "The data generated by our program is used to inform installation leaders on the levels and types of influenza or other respiratory outbreaks early, allowing it to be quickly addressed by Public Health personnel."

USAFSAM and the DoD Global, Laboratory-based Influenza Surveillance Program will continue to monitor global trends in influenza and other respiratory illnesses to help base installations make decisions and take public health actions like influenza and respiratory hygiene education campaigns, promotion of vaccination, and mandatory quarters for those affected.  The data collected at USAFSAM will also continue to help CDC inform the U.S. civilian population be aware of and vigilant against current influenza trends.