A total of 23 medical groups, nursing organisations and lawmakers issued an urgent appeal to parents, children, pregnant women, patients with chronic conditions, the elderly and their carers to stay alert and take appropriate precautions during the peak of the flu season.

This warning comes as flu cases are rising in Hong Kong and across Asia, including in countries such as South Korea, Indonesia, Malaysia and Singapore.

The Asian Society for Paediatric Infectious Diseases, one of the signatories, called for children to be given flu vaccinations more quickly.

The society's president, Mike Kwan, emphasised that vaccination is the most effective way to build immunity against influenza, which can lead to serious complications.

Its president Mike Kwan emphasised that vaccination is the most effective way to build immunity against influenza, which can lead to serious complications.

"The most worrying is the complication of the flu infection, like when an individual have pneumonia or have a brain infection and what we call encephalopathy, then the individual may have change in consciousness and also reduced response to other people." he said.

"And also one condition is what we call myocarditis, the inflammation of the heart muscle. The individual may have low blood pressure and also multi-organ failure," he added.

He mentioned that people can choose from different types of vaccines, including recombinant, inhaled and inactivated options provided by the government.

Dr Kwan also stressed the importance of good hygiene practices such as handwashing, wearing masks and ensuring good ventilation, to help reduce the spread of illness.

He also pointed out that flu symptoms can resemble those of a common cold. Caregivers should seek immediate medical attention if severe symptoms occur, such as shortness of breath, chest pain, decreased appetite and an increased heart rate.