Uttarakhand has recorded 3,846 dengue cases this year and seven people have died. This is the highest figure of dengue patients in the state in the past several years. With maximum cases being reported from plains as compared to hills, Health department officials are citing climate change as a reason for spread of the disease.
According to the data of Health and Family Welfare department, 3,799 cases of dengue have been reported in four districts of the state till Friday. Health officials are saying that the number may increase because post-monsoon weather will continue till mid-October.
This year, till September 20, 2,434 dengue cases have been reported in Dehradun and six people have died. This is followed by tourism destination Nainital, where 1,134 patients have been diagnosed with dengue and one of them has died. Haridwar district accounts for 146 cases, followed by Udham Singh Nagar (85).
Besides these, 15 cases have been reported in Tehri Garhwal, 12 in Pauri Garhwal, nine in Almora, six in Rudraprayag, three in Bageshwar and two in Champawat.
Behind outbreak, change in rain pattern
According to officials of the health department, the rise in the number of dengue cases is due to a change in the pattern of monsoon rainfall. In the past three years, monsoon rain was regular and water in drains and other open places like gardens never stagnated. But, this year, rainfall has occurred irregularly with sunny days in between, leading to humidity. Stagnant water and humidity are ideal conditions for breeding of dengue larvae. The officials also said less dengue cases were reported in the hills because rainwater did not stagnate there.
According to government data, in 2016, 2,046 dengue cases were reported from across the state and four people had died. In 2017, the number of dengue cases came down to 849 and no death was reported. In 2018, the number of cases further dipped to 591 and two people died.
Dr Pankaj Singh, Assistant Director (Integrated Disease Surveillance Programme), Health and Family Welfare department, said the geography of hill areas combined with low temperature and humidity do not support a dengue outbreak and breeding of the vector Aedes Aegypti. He said dengue is a climate change-driven disease and its larvae reproduces in temperatures between 20°C and 30°C and humidity above 60 per cent. Such conditions, he said, was in plain areas like Dehradun.
“In conditions of normal monsoon and heavy rain, dengue cases were reported from September to mid-October when water remains stagnant and humidity rises after the end of monsoon. This year, dengue cases have been reported much earlier because of less and disrupted rain,” Singh said.
Singh also said more dengue cases have been diagnosed this year because more ELISA test centres have been opened.