How serious is the flu outbreak in Hong Kong?

More patients are testing positive for flu viruses, according to the Centre for Health Protection, from 13.5 per cent in mid-May to over 40.6 per cent in the second week of this month, the South China Morning Post (SCMP) reported.

The shortage of staff and beds at public hospitals is so bad that some patients have had to wait for more than 12 hours to get admitted. And patients whose illness was not life-threatening had to wait at least six hours to see a doctor.

What is unusual about the flu season this summer?

This summer's flu peak period started in May, one month earlier than two years ago, according to SCMP.

Since May, there have been 300 reported severe flu cases, compared to 50 in the same period last year. In 2015, the number between May and July was about 180.

Usually, such a situation would last about two or three days, but this year, it has lasted for more than 10 days.

Should travellers avoid visiting Hong Kong?

Visitors to the city should not be worried, said Dr Leung Chi Chiu, chairman of the Medical Association's Advisory Committee on Communicable Diseases, because the dominant strain in the current outbreak is not a new one.

But experts are divided on the severity of the flu strain in this outbreak. One medical expert said the outbreak is partly because the flu vaccine given in November last year has started to expire. Another said the outbreak could be due to a lower flu peak last winter. But a third said a mutation in a dominant flu strain might be the cause of the current crisis.