Hong Kong parents have been urged to vaccinate their young children as cases of influenza among children have risen across the city.

Children play in a playground in September 2026. Photo: Kyle Lam/HKFP.

Mike Kwan, honorary clinical associate professor of the Department of Paediatrics and Adolescent Medicine at the University of Hong Kong, said on Commercial Radio on Monday that flu-related hospitalisations of children have risen recently, with some patients experiencing fevers in excess of 40 degrees Celsius that persist for several days.

Kwan said the city is currently in the summer flu season, which is yet to reach its peak. The summer flu season in Hong Kong usually begins in June, with the winter flu season starting in January. He urged parents to vaccinate their young children against influenza, which he said provides the strongest protection against serious illness.

The Government Vaccination Programme for 2026/27 will commence this Thursday, offering free vaccines for high-risk groups such as children aged six months or older, pregnant women, and the elderly.

Director of Health Ronald Lam told RTHK on Saturday that the vaccination rate among children aged six months to two years is 27 per cent—much lower than the rate among older children.

Director for Health Ronald Lam (first from left) talks to children who are about to receive flu vaccines in a school in October 2025. Photo: GovHK.

According to government figures, more than half of children aged six months to six years old were vaccinated against flu in the 2025/26 season. Over three-quarters of children aged six to 12 got flu jabs.

Severe paediatric flu cases

Lam said Hong Kong has seen “wave-like rise” in flu cases since June.

The proportion of people seeking medical attention or requiring hospitalisation due to the flu rose from 0.27 cases per 10,000 people during the same period last year to 0.83 cases this year, the director of health said.

Currently, over 80 per cent of cases are Influenza A (H1), nearly 20 per cent are Influenza A (H3), and a small number are Influenza B cases.

According to the director of health, Hong Kong recorded 19 severe paediatric flu cases this year.

Among those, eight cases involved children under five years old, five of whom were unvaccinated.

Lam said that unvaccinated young children face over five times the risk of severe illness from flu infection compared to those who were vaccinated.