Influenza Outbreak During Exercise Talisman Sabre, Queensland, Australia, July 2019

Area of Science:

• Military Medicine
• Infectious Disease Epidemiology
• Public Health

Background:

• Influenza outbreaks can disrupt large-scale military exercises.
• Suboptimal influenza immunization rates among military personnel pose a risk during deployments.
• Exercise Talisman Sabre (TS-19) in Australia presented a unique setting for observing influenza transmission in a military population.

Purpose of the Study:

• To document the occurrence and impact of influenza during Exercise Talisman Sabre 2019.
• To identify factors contributing to influenza spread within the military contingent.
• To assess the resource burden of managing influenza-like illness (ILI) during a major military exercise.

Main Methods:

• Surveillance of influenza-like illness (ILI) among participants of Exercise Talisman Sabre 2019.
• Rapid diagnostic testing to confirm influenza A and B infections.
• Analysis of immunization status and vaccine types received by affected personnel.

Main Results:

• A total of 76 cases of ILI were reported, with 43 confirmed influenza cases (32 Influenza A, 11 Influenza B).
• Suboptimal immunization was noted, with Australian/New Zealand forces having low uptake of the Southern Hemisphere vaccine and U.S. forces receiving the Northern Hemisphere vaccine.
• Despite overall low disease rates (<1%), influenza management required significant medical resources.

Conclusions:

• Influenza posed a considerable challenge during Exercise Talisman Sabre 2019, impacting operational readiness.
• Inadequate and mismatched influenza vaccination contributed to the outbreak.
• Effective influenza surveillance and management strategies are crucial for military operations, even at low endemic levels.