Hong Kong is planning free flu vaccinations for 1 million children aged 12 and under to prevent further spread of the epidemic.

The project would cost about HK$100 million ($13 million), said Hong Kong Secretary for Food and Health York Chow on Friday, one day before five more school children were suspected of contracting the virus.

The large-scale initiative will be evaluated by the Commission of Science of Hong Kong.

Health authorities said the virus was running wild in Hong Kong's community and schools after killing four children and infecting increasing numbers of people, as investigations began on the five new cases to confirm whether flu was the culprit.

Flu was found to have caused the deaths of two children in Hong Kong earlier this month. On March 1 a child died from H1N1 and another from H3N2 on March 14.

Both strains have appeared in different countries in past months.

The results prove the children did not die of any new or more virulent virus, a spokesperson for Hong Kong's Center for Health Protection said.

The speaker said outbreaks were getting worse in Hong Kong as the city grows more crowded and the conditions more conducive to cross infection.

Chow said the possibility of extending school closures could not be ruled out if the situation didn't improve.

Sources from the World Heath Organization (WHO) said the current outbreak was not out of the ordinary for the peak flu season, and that the WHO would keep an eye on the situation in Hong Kong, according to www.cri.cn.

Meanwhile, neighboring Guangdong province launched an overall flu surveillance mechanism on Saturday.

The mechanism will detect any new outbreaks and notify relevant departments when to adopt emergency control measures.

The provincial health department said the flu-B virus that had appeared in Guangdong did not vary.

People should not panic because flu-B is much less virulent than flu-A, which is spreading in Hong Kong, Lin Jinyan, vice-director of the Guangdong Center for Disease Control and Prevention (CDC), said on Friday.

He said he believes that the province has sufficient experience to handle the current flu outbreaks.

The provincial health and education departments have jointly ordered all kindergartens, elementary and middle schools to examine their students' health every morning.

"No school has been closed so far," Lin Jinyan said. "But people who have contracted flu should stay home from school or work."

Experts say the number of flu patients will not significantly fall until the end of April.

Until now, Guangdong has reported just five outbreaks in which 15 people have contracted the virus.

Shenzhen, Zhuhai, and Shaoguan each have had one outbreak and Guangzhou two, according to the provincial health department.

Influenza is most active between March and July.