People are being urged to get vaccinated against flu as quickly as they can amid fears Hong Kong's current summer season for the virus could stretch past the end of the year and overlap with its winter season.

The city's latest seasonal influenza vaccination programme is now underway, with eligible high-risk groups able to get free or subsidised jabs from more than 1,700 private doctors, as well as from public health centres, outpatient clinics and hospitals.

Dr Sy Wing-man, an associate consultant from the Hospital Authority’s Kowloon West Cluster, said flu infections have been on the rise in the past two weeks and are expected to remain high for the time being.

“Since September, there were already seven severe cases of paediatric influenza A infection. Hong Kong’s winter flu season usually starts from January to March and we are a bit worried that the summer flu period would extend till January and overlap with the winter one,” she said.

“In that case, it will impose a stronger burden on our medical system. Therefore, we hope citizens can take preventative measures as quickly as possible.”

The government has taken a number of steps to try to increase the vaccination rate this year, including expanding the coverage of free and subsidised jabs to include people aged 18 to 49 with chronic illnesses, providing 100,000 additional inactivated jabs for private doctors, and allowing schools to opt for a nasal spray version.

Sy said she thinks the moves will help persuade more people to protect themselves against the virus.

"Last year, more than 2.08 million people got the flu jab. We are optimistic about the situation this year. The government has rolled out five enhancement measures hoping to further boost the inoculation rate, and we are also happy to see that the citizens care about flu vaccines. So we believe they understand the importance of flu vaccinations," she said.

Sy added that pregnant women can choose from at least two types of flu shots, based on their health situation.