Fear of different viral strain as dengue cases rise
As dengue cases continue to surge, experts fear a possible switch in viral type could lead to a major epidemic and more serious illness.
Another worry is that the surge has come in the traditional lull period. Dengue is usually most common in the hot months from April to October when the Aedes mosquito, which transmits the disease, breeds faster.
But the numbers in the past two weeks have been above the epidemic threshold of 165 weekly cases – beyond which point the disease can spread rapidly.
Last week, 220 people were diagnosed with the viral disease, up from 208 in the previous week. With more than 100 people coming down with the ailment in the first three days of this week, the spread appears unabated.
There are now 24 active dengue clusters. The biggest, in Telok Kurau, has 68 people down with the disease. This cluster is caused mainly by the Den-1 virus. It is also seen in other areas such as Hougang, Kaki Bukit and Geylang.
There are four strains of dengue virus with Den-2 being dominant for the past five years and responsible for 75 per cent of the cases. A switch in the dominant strain could mean that many people would lack immunity.
Even more worrying is that someone who has had a previous attack of dengue and is infected by a different viral strain the second time, would tend to become more sick, possibly even with the potentially fatal dengue haemorrhagic fever.
In 2011, Den-1 accounted for 10 per cent of infections. Last month, it accounted for 30 per cent.
Associate Professor Leo Yee Sin, clinical director of the Communicable Disease Centre, said some of the more serious dengue victims will inevitably end up in hospital.
“We are hence anticipating an increased demand for hospital beds,” she added.
This will add to the bed crunch already faced by public hospitals. Latest figures show four of the six public hospitals with bed occupancy rates of more than 90 per cent.
Prof Leo said that while Tan Tock Seng Hospital has been seeing more dengue cases in recent weeks, “we have not encountered (anything to suggest), nor can we conclude that, the patients are more ill as compared to the previous dengue cases”.
However, she added that the situation will be monitored closely.
She urged people, especially those who live in areas known to have dengue, to see a doctor immediately should they have a sudden onset of fever, aches and pain.
Source: The Straits Times
Category: Health alert