Mosquito spreading two types of fever

SINGAPORE - The Aedes mosquito is wreaking havoc in Singapore, spreading not just dengue fever but more recently the very painful chikungunya as well.

This month alone, 56 people have become sick with chikungunya - which translates from an African language as "to become contorted".

This is up from just 22 for the whole of last year. Symptoms include a sudden fever and severe joint swelling and pain. Victims often also suffer from muscle pain, headache, nausea, fatigue and rashes. It is rarely fatal and lasts between several days to a week - although some people have complained of continued joint aches for months and years.

In spite of the National Environment Agency's best efforts, the number of chikungunya infections has been growing over the past month - from six in the first week of April, to 15 in the second, and 35 in the third.

A Health Ministry spokesman said that of the 35 people infected last week, 27 are foreign workers and two are Singaporeans who live or work around the Kranji-Sungei Kadut area. The other six are residents in the Fifth Avenue, Sixth Avenue and Trevose Crescent area along Bukit Timah Road.

Meanwhile, Singapore also appears to be losing its fight against the spread of dengue, which has infected more than 5,000 people so far this year.

Both dengue and chikungunya are viral diseases that can be spread only by mosquitoes.

About 110 people were hospitalised for dengue last week out of the 510 who were infected. More will need such care this week as the number of infections continues to soar, with another 386 diagnosed with dengue since Sunday.

Experts have predicted a huge dengue epidemic this year as the current surge in cases comes before the usual peak during the hotter months in the middle of the year. The change in the dominant type of dengue virus means fewer people are immune to it.

There are four types of dengue viruses. Once infected, a person is protected against that viral type but can still be infected by any of the other three.

According to the Ministry of Health, about one in three people diagnosed with dengue end up in hospital - or about 1,600 of the 5,000 cases so far this year. In the 2005 epidemic, 14,000 people were infected and 25 died.

But Associate Professor Leo Yee Sin, clinical director at the Communicable Disease Centre, hopes that the experience doctors have gained over the past years will mean fewer or perhaps no deaths at all this year, even if infection numbers go up.

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