Bindu Shajan Perappadan

Research shows the dengue virus prevalent this year is not the virulent variety

NEW DELHI: With the number of dengue cases in the Capital on a steady rise, researchers are still working at deciphering the specific dengue virus that has led to the excessive patient load on the Government hospitals in the city.

The research so far has shown that the dengue virus prevalent this year is not the virulent variety, but the bad news is the fact that doctors are seeing a large number of patients who have caught the virus the second time round this season.

Dengue is caused due to virus 1, 2, 3 and 4, of which 2 and 4 are the virulent variety.

"After analysing the samples that were sent to us we have found that the maximum number of cases have been reported with dengue virus 3, which is comparatively less harmful. This virus was first seen in the Capital in 2003 and while the following years did see a mixed presence of virus in the general population, this year the dengue virus 3 has made a comeback of sorts. The dengue virus we have analysed has the tendency to repeat the cycle after two to three years and we might be seeing a repeat of 2003," said National Institute of Communicable Diseases director Dr. Shiv Lal.

He added that researchers at the country's premier medical institution, the All-India Institute of Medical Sciences (AIIMS), have also found dengue virus 2. "But the presence of dengue virus 2 in general population is very limited," Dr. Lal said.

"Dengue virus 2 had caused heavy mortality due to haemorrhages in the 1996 outbreak. However, dengue virus 3 does not cause very high mortality. Any patient can be infected with at least two, if not all four types at different times during their lifetime, but only once by the same type," said a senior official at AIIMS.

A senior official at the Delhi Disaster Management Authority said: "Till dengue is not declared an epidemic, we don't see the need for us to step in. "