Core Insights - The H3N2 influenza virus exhibits a characteristic of "symptom-free transmission," meaning individuals can spread the virus at least 24 hours before showing any symptoms [1] - The efficiency of H3N2's transmission is approximately 30% higher than that of regular influenza, contributing to the rapid spread of the current winter outbreak [1] Group 1: Virus Characteristics - H3N2 has a faster replication speed and a shorter proliferation cycle within respiratory cells [2] - The virus has enhanced immune evasion capabilities, allowing it to partially bypass the body's initial immune defenses [2] - The viral load during the asymptomatic phase is sufficient to infect others, explaining simultaneous outbreaks in offices and classrooms [2] Group 2: Prevention Recommendations - The most effective time to implement preventive measures is during seemingly "calm" periods of the outbreak [2] - It is advised to assume the presence of infected individuals in crowded places and to enhance protective measures accordingly [2] - Individuals should practice "pre-symptom protection" by tracing contact history and self-monitoring when family members or colleagues show signs of discomfort [2]