Influenza Resurgence after Relaxation of Public Health and Social Measures, Hong Kong, 2023

Abstract

Soon after a mask mandate was relaxed (March 1, 2023), the first post–COVID-19 influenza season in Hong Kong lasted 12 weeks. After other preventive measures were accounted for, mask wearing was associated with an estimated 25% reduction in influenza transmission. Influenza resurgence probably resulted from relaxation of mask mandates and other measures.

Keywords

• Influenza
• reproductive number
• impact of public health and social measures
• face mask
• viruses
• COVID-19