Influenza A outbreak forces school quarantines in Shanghai and Hangzhou

A significant outbreak of influenza A, primarily the H3N2 strain, has been reported in Shanghai and Hangzhou, leading to widespread school disruptions. Following the start of the new school term, numerous primary schools and kindergartens have implemented mandatory home quarantine for entire classes due to high infection rates.

In Shanghai, some classes have reported nearly half of their students being absent due to illness. Data indicates a sharp rise in influenza cases; in July, reported cases in Shanghai reached 22,020, a nearly threefold increase from June. In Hangzhou, schools have issued notices for students to suspend classes for several days after a high proportion of students fell ill with fever.

Medical facilities in the region are seeing a surge in pediatric visits. At Hangzhou Children's Hospital, doctors noted that influenza-related hospitalizations now account for approximately one-third of total ward beds. While H3N2 is the dominant strain, infections of Influenza B (Victoria lineage) have also been observed, with young children and primary school students identified as the most affected demographic.