Dengue infections at five-year high

SINGAPORE - There is still no sign of an end to the dengue epidemic, with last week's figure of 267 people down with the disease the highest weekly tally in more than five years.

And 85 people have already been infected in the first three days of this week, in a continuation of a steadily growing trend since mid-December.

Dr Mukund Doshi, a private specialist in internal medicine, said he has warded more than 30 patients in Parkway East Hospital this month alone.

He has between seven and 10 patients in the hospital at any one time, compared to a norm of three to four. The hospital is near the biggest cluster of cases today - in the Telok Kurau area - where 81 residents have fallen ill.

The internist, who has been practising for more than three decades, said the illness also appears to be more severe.

"Patients' blood platelet counts drop faster than usual, there is more vomiting and diarrhoea and many have high fever," he noted.

Platelets help blood to clot. A normal person has 145,000 to 450,000 platelets per microlitre of blood. Dr Doshi said he has seen patients this month with counts of as low as 10,000.

But he has not seen any serious haemorrhaging cases this month, only some bleeding in the gums or nose, he added.

According to the Ministry of Health, six cases of the more serious dengue haemorrhagic fever had occurred this year.

The disease in the Telok Kurau cluster is caused primarily by the Den-1 virus.

One fear experts have is a change in the dominant virus type causing infections.

There are four dengue viruses, with Den-2 dominant in the past six years. A change in the dominant strain usually heralds a major outbreak.

Den-1 caused 10 per cent of the infections in 2011. The figure went up to 19 per cent last year, and 27 per cent in the first three weeks of this year.

A spokesman for the National Environment Agency (NEA) said about two-thirds of the mosquito-breeding sites found in the Telok Kurau area were in homes.

Mosquito breeding was also detected at several construction sites. She said the contractors at seven sites had been handed fines of between $2,000 and $5,000 while the contractors at two other sites will be taken to court for repeated offences.

The NEA no longer fogs to kill mosquitoes "as it is neither sustainable nor effective", the spokesman said. Instead, it finds and destroys mosquito-breeding areas.

salma@sph.com.sg

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