Karnataka has the second highest number of dengue cases in the country this year. While Tamil Nadu tops the list with 2,361 cases, Karnataka follows with 1,417 cases reported from January till April 30 this year.
According to data from the National Vector Borne Disease Control Programme (NVBDCP), under the Union Ministry’s Directorate General of Health Services, Karnataka has always been one among the top ten States in the country with a high incidence of dengue.
Alternate year
Health officials said dengue in Karnataka has been following a pattern of spiking every alternate year. The number of dengue cases in the State had gone up from 3,358 in 2014 to 5,077 in 2015, 6,083 in 2016 and 17,844 in 2017. In 2017, Karnataka was behind Tamil Nadu and Kerala that reported 23,294 and 19,994 dengue cases, respectively. Karnataka reported 4,427 cases in 2018, 18,183 in 2019, 3,823 in 2020 and 7,393 in 2021. Officials said the rise in cases this year is seen mainly in urban areas, where construction work has begun after the decline in COVID-19 cases.
According to Karnataka’s Health Department data, there has been a 36.33% rise in dengue incidence this year - from January till May 12 compared to the corresponding period last year. Till May 12 this year, 1,335 cases were reported while 850 cases had been reported in the corresponding period last year. In 2020, 1,792 cases were recorded during the same period. In the last one month alone, nearly 300 cases have been added to the State’s tally.
Of the 1,335 cases this year, the most (393) were reported in February while 302 were recorded in March. In January, a rise of over 86% was recorded compared to the corresponding month last year. While 33 cases were recorded in January 2021, 244 cases were reported in the same month this year. However, there have been no deaths so far.
Contributing factors
Experts involved in vector borne disease control programmes said the transmission of dengue is governed by various ecological factors. This coupled with unplanned developmental activities, improper water storage, migration and improper solid waste management also play a crucial role in the upsurge of dengue cases. Dengue-causing aedes aegypti mosquitoes breed in freshwater and bite during the day.
Susanta Kumar Ghosh, former scientist and head, field station of ICMR-National Institute of Malaria Research in Bengaluru, said although dengue was earlier associated with the monsoon, it has now become a self-limiting viral fever which is prevalent all through the year.
Robust reporting
State Health Commissioner Randeep D. told The Hindu that the high incidence in Karnataka is because of a robust reporting system. “Unseasonal rains, rapid urbanisation and construction activities have added to the problem. We have intensified awareness and are regularly conducting campaigns to educate people about preventive measures,” he said.
K.V. Trilok Chandra, BBMP’s Special Commissioner (Health), attributed the dengue spurt in the city to intermittent rains and resultant water logging. “Our health workers are conducting larvae surveys via door-to-door visits. We have intensified awareness and preventive measures. To mark National Dengue Day on May 16, a jatha is being taken out to make people aware about prevention measures,” he said.
BBMP tops
With 22.6% of the State’s total cases this year being reported in Bengaluru, the city continued to record the highest number of positive cases. From 232 cases in April, Bengaluru’s dengue tally shot up to 302 on May 12.
After BBMP, a significant rise has been recorded in Udupi, Mysuru, Koppal, Chitradurga and Vijayapura districts from January to May compared to last year.
Data showed that Udupi has recorded the highest number (150) - from January to May - among districts other than Bengaluru. Udupi is followed by Mysuru (127), Koppal (87), Chitradurga (79) and Vijayapura (48).