Hong Kong may enter its summer flu season earlier than usual this year, with a peak likely to occur later this month, health authorities have said, urging unvaccinated residents to receive jabs for protection.Dr Edwin Tsui Lok-kin, controller of the Centre for Health Protection, said on Tuesday that influenza activity in the city had increased since May.He noted that the last summer flu season extended from September to January, and with no winter flu season earlier this year, this summer’s...