Dengue
Health department officials in the states attribute the spurt in numbers to drought.
Representative image

Karnataka, Kerala and Tamil Nadu have reported an alarming increase in the number of dengue cases in 2017. The number of cases reported in the three states has doubled in the last year.

Tamil Nadu tops the list with 23,035 positive cases of dengue in 2017. This is as per figures available with the National Vector Borne Disease Control Programme (NVBDCP). TN reported 2,531 cases in 2016.

The number of deaths due to dengue have also gone up manifold. The state saw five deaths in 2016 due to dengue, but in 2017, the number rose to 63.

There was a spike in the number of cases being reported in other South Indian states as well. In Kerala, the number of cases reported was as high as 19,912. In comparison, there were 7,349 cases in 2016.

Speaking to TNM, Dr Kalpana Barua, NVBDCP Kerala, said that the numbers had gone up in most states in the country.

“It is an outbreak-prone disease. The numbers could vary because of that. Also, there might have been variations in the virus itself,” she said.

She added that the number of them getting affected also depends on the immunity status of the people.

Karnataka stands third in terms of the number of cases reported. While the state saw 6,083 cases in 2016, the number went up to 17,018 (17,339 as per figures with the state’s health department) in 2017. The number of deaths, however, reduced from eight to five. The state stands third with respect to the number of cases reported, but tenth in terms of the number of deaths. This was out of 85,067 samples that were tested in laboratories across Karnataka.

The reason

Health department officials in the states attribute the spurt in numbers to drought. Due to acute shortage of water, people in drought-affected areas store water in several containers to be able to manage their water needs. When these containers are left uncovered, they become ideal breeding grounds for mosquitoes, leading to a spurt in the number of dengue cases.

The Karnataka health department explained that with the late onset of monsoon, there was an increase in the number of people using storage containers, which could have made room for a lot of mosquito breeding. The department estimated that there was a 150 % increase in the number of storage containers due to this.

In urban areas and taluk quarters, the health department has also deployed junior health assistants to conduct screenings on vector-borne diseases on the first and third Friday of each month.

Officials in Tamil Nadu also believe this is the reason for the increase in cases. Speaking to TNM, Dr K Kolandaswamy, director, Director of Public Health, Tamil Nadu said that most cases were reported in drought-affected areas.

“Places around Coimbatore, Dharmapuri, Salem and Erode reported high numbers. These were severely affected by drought,” he added.

Better surveillance?

He also said that the NVBDCP figures did not have details of the area covered or the population. “In a place like Coimbatore alone, 4,000 cases were reported. This is because the diagnostics and surveillance is better there,” Dr K Kolandaswamy said.

The Department of Health and Family Welfare, Karnataka also attributed the increase in numbers to better surveillance. They explained that with most samples of viral flu being given for testing, the number of dengue cases being reported is also higher.

In a note, the health department said that the Bruhat Bengaluru Mahanagara Palike, the civic authority in Bengaluru also bettered its systems, due to which over 7,000 cases were reported from the Palike limits alone. In 2016, just 10% of total cases were reported. In 2017, the BBMP added data from cases reported in private hospitals as well, which did not take place in 2016.