Dengue sample tests show predominance of 2 strains
Times of India | 9 October 2025Though the number of cases, as well as severity, is comparatively low this year, health officials and hospitals have been witnessing a gradual spike in the past week. Experts said numbers will continue to trickle in until the mercury subsides to a certain level.
"We have sequenced 454 dengue-positive samples so far, which came to us from Kolkata and South 24 Parganas. So far, we have found DEN 2 and DEN 3 to be the predominant," said ICMR-NIRBI director Santasabuj Das.
At the institute, dengue positivity, which was less than 1% until the end of Aug, has now gone up to around 3.3%. Serotyping is done every year to identify the circulating strain as part of surveillance.
"DEN 2 and DEN 3 are known to be the most virulent strains. But this time, so far, the severity does not seem to be very concerning. However, there is a slight uptick in cases as we are finding more positive samples in our lab.
The number, though, is not yet alarming," said Bhaskar Narayan Chaudhuri, chief microbiologist at Peerless Hospital.
Experts said out of the four dengue strains that cause the infection, in the past few years, DEN 3 has been predominant, followed by DEN 2. While DEN 1 is found in a few cases in the state, sources said DEN 4 has not been detected so far.
"We are seeing an uptick in the past five-six days. While we have come across a few severe cases, we have been able to treat them. The treatment success lies in consulting doctors at the earliest. We have to be careful, especially those with comorbidities," said associate professor Yogiraj Ray, head of infectious diseases, IPGMER.
