Small but unusual rise in dengue cases in Singapore

Imelda Saad, Channel NewsAsia 14 Nov 08;

SINGAPORE: There has been a small but slightly unusual rise in the number of dengue cases in Singapore.

While incidence of the disease usually starts falling after its seasonal June-September peak, figures this year showed a 14 per cent rise over the same five-week period in September and October last year.

The National Environment Agency (NEA) attributed the rise to a small 0.2 degree Celsius increase in average temperature some 12 weeks ago.

It said warm temperatures have the effect of shortening the life cycle of the Aedes mosquito from seven to 10 days to five to seven days. The virus also replicates faster, resulting in more opportunities for the mosquito to transmit dengue.

NEA also found a 50 per cent rise in the number of breeding sites in homes in the same period over last year.

It identified 15 areas where dengue transmission has increased recently. They include Joo Chiat, Hougang Avenue 8 and Clementi West.

Intensive source reduction operations are being carried out in the affected areas.

NEA said some 20 to 40 per cent more staff have been sent to these areas. It added the cases are mostly sporadic and clusters small in size.

The agency said the best defence against Aedes mosquito-borne diseases is the removal of potential breeding grounds. It said residents should also regularly perform the 10-Minute Mozzie Wipe Out.

- CNA/ir