Hong Kong health authorities on Thursday confirmed that a five-year-old boy had died from scarlet fever, the second death in the southern Chinese city as dozens of new cases were reported.
The number of infections in the territory has soared above 500, according to health authorities, who said that more than 9,000 people had been infected in the Chinese mainland -- doubling the average figure in recent years.
Local scientists said the outbreak may be linked to a deadly new strain of the disease which could make it more contagious than before.
It was discovered by researchers at the University of Hong Kong and appears to be resistant to antibiotics traditionally used to fight the illness.
"Test results showed that the five-year-old boy who died on Tuesday is confirmed to have suffered from scarlet fever," a spokeswoman from the Centre for Health Protection told AFP. The test result was released late Wednesday.
The second fatality comes after the illness, which mainly affects children aged between two and eight, claimed the life of a seven-year-old girl last month.
It was the first recorded death in the city in at least a decade, according to the Centre for Health Protection.
The government said Tuesday that the boy, who had chicken pox prior to his death, was "very likely" a victim of scarlet fever, after declaring an outbreak of the disease in the city of seven million.
The Centre for Health Protection spokeswoman said the boy's brothers, aged seven and 13, had also been tested for scarlet fever and results were still pending.
Classes have been suspended at the boy's kindergarten for a week, a first for Hong Kong following a scarlet fever death.
The kindergarten did not immediately respond to AFP's requests for comment but a statement posted on its website said the school has "stepped up disinfection work".
The Centre for Health Protection said 32 new cases had been reported in Hong Kong on Thursday, the highest number of daily new cases this year, with the total number of scarlet fever cases in the territory at 526.
Peter Cordingley, a spokesman for the World Health Organization, said Thursday that WHO is "still trying to build a picture of the situation".
"The problem is that scarlet fever is not a notifiable disease and because it is usually so mild and easily treated with antibiotics, it often goes unnoticed," he added.
Hong Kong is particularly nervous about infectious diseases following the 2003 SARS outbreak, which killed 300 people in the city and a further 500 worldwide.
The densely populated city of seven million has also seen fatalities from multiple swine flu outbreaks.
In Macau, a short ferry ride from Hong Kong, 49 people have contracted scarlet fever but there are no fatalities so far this year, according to Macau health authorities.
Scarlet fever symptoms include fever, sore throat, rashes and a "strawberry coloured" tongue, and usually subside within 48 hours with appropriate antibiotic treatment.
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