Hong Kong: Children hardest hit by swine flu

Natalie Wong

Monday, September 06, 2010

Up to 45 percent of children aged five to 14 were infected with H1N1 during the first wave of the swine flu pandemic in Hong Kong last year, according to a serological study announced at an international flu symposium.

The University of Hong Kong collected blood samples from 40,000 citizens from June to November 2009, and found 11 percent of the local population was infected with swine flu.

The 45 percent infection rate of children was highest. Citizens aged 15 to 59 had infection rates of between 7 and 20 percent.

The five-day flu symposium, which ends tomorrow, is being attended by international influenza specialists at the Hong Kong Convention and Exhibition Centre.

"When half of the Hong Kong children were infected with a virus from nowhere, can you just ignore this situation and not make any protective measures?" asked conference chairman Malik Peiris, professor in microbiology at HKU.

The findings justified the government's draconian measures to play safe in the beginning of the outbreak last year. For instance, school suspension was essential in June last year to control transmission, according to another professor from the department, Dr Poon Lit-man.

When the first swine flu case was confirmed in May last year, the government quarantined visitors at Metropark Hotel in Wan Chai for seven days.

After the early outbreaks in North America in April 2009, the pandemic spread around the world.

Figures released last month by the World Health Organization showed 18,630 laboratory-confirmed deaths were reported in 125 countries.

The WHO declared last month that the swine flu pandemic was officially over. The organization's head of Global Influenza Program, Sylvie Briand, said although the virus is relatively mild, there was widespread community transmission in all areas.

"We have to continue with a global network of surveillance, as it is impossible to predict when the ever changing influenza virus is going to mutate," said Briand, who also defended the WHO against accusations that it hyped the swine flu pandemic.

"We prepared for the worst and hoped for the best, and as the information became available, there was adaptation of the plan, and adaptation of the recommendations in order to really tailor the response to the reality. But it took some time."

In Hong Kong, 2,491 swine flu cases were recorded in the first half of the year, with the July figure of 79 cases dropping from 1,092 cases in January. the Centre for Health Protection said.