Kasetsart University, Sakon Nakhon, Thailand; Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; Corresponding author at: Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand.
Sutthichai Nakphook
Kasetsart University, Sakon Nakhon, Thailand; Thailand Ministry of Public Health, Nonthaburi, Thailand
Darunee Ditsungnoen
Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand
Patranuch Sapchookul
Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand
Kanlaya Sornwong
Kasetsart University, Sakon Nakhon, Thailand
Suriya Naosri
Kasetsart University, Sakon Nakhon, Thailand
Pilailuk Akkapaiboon Okada
Thailand Ministry of Public Health, Nonthaburi, Thailand
Piyarat Suntarattiwong
Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; Queen Sirikit National Institute of Child Health, Bangkok, Thailand
Tawee Chotpitayasunondh
Queen Sirikit National Institute of Child Health, Bangkok, Thailand
Martha P. Montgomery
Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
William W. Davis
Thailand Ministry of Public Health-U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
Chakrarat Pittayawonganon
Thailand Ministry of Public Health, Nonthaburi, Thailand
Thai Ministry of Public Health recommends influenza vaccination for certain risk groups. We evaluated 2023 Southern Hemisphere influenza vaccine effectiveness against medically attended influenza using surveillance data from nine Thai hospitals and a test-negative design. During June 2022–May 2023, influenza vaccine provided moderate protection against seeking care for influenza illness (adjusted vaccine effectiveness 51%; 95% confidence interval 28–67). Understanding vaccine effectiveness can help guide future antigen selection and support clinicians to make a strong influenza vaccine recommendation to patients.
