First dengue vaccine that will hit shelves next year 'looks promising', experts say

A dengue alert banner in Lorong L, Telok Kurau, which is part of the biggest cluster with 50 infections as of Jan 17, 2013. The world's first dengue vaccine will hit the shelves next year, following the completion of its phase three trials that
A dengue alert banner in Lorong L, Telok Kurau, which is part of the biggest cluster with 50 infections as of Jan 17, 2013. The world's first dengue vaccine will hit the shelves next year, following the completion of its phase three trials that found it 56 per cent effective. -- PHOTO: ST FILE

SINGAPORE - The world's first dengue vaccine will hit the shelves next year, following the completion of its phase three trials that found it 56 per cent effective.

"It is promising, but not perfect," said Infectious Diseases expert Professor Annelies Wilder-Smith of the Lee Kong Chian School of Medicine.

This is because dengue has been rising over the years in spite of the best efforts to keep it at bay, and there is currently nothing else to fight the mosquito-borne disease.

Singapore dengue numbers hit a new high last week with 891 cases, and since Sunday, another 630 people have fallen ill.

The results of the clinical trial of Sanofi's dengue vaccine on more than 10,000 children in Asia, published in the Lancet July 11, showed that its effectiveness varried with the four dengue strains.

The children aged 2-14 years were given three jabs of the vaccine over one year, and were followed up for another two years.

The protection was highest at 75 per cent for Den-3 and Den-4, 50 per cent for Den-1 and 35 per cent for Den-2. Unfortunately, Den-1 and Den-2 are the virus most commonly found in Singapore.

Dr Wilder-Smith said another drawback is the trial was on children, but in Singapore, the majority of dengue victims are adults.

But she added that it might actually work better in adults. This is because the vaccine was found to work better in children who had been infected previously.

In Singapore, 45 per cent of adults would have had a dengue infection by the age of 45, though many might not be aware of it as their symptoms could have been mild.

Dr Wilder-Smith said that a plus point for the vaccine is that it reduced the serious form of dengue by up to 80 per cent.

However, whether it is cost effective to vaccinate the population will depend on the pricing, which has yet to be announced.

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