CHENNAI: In positive news for Tamil Nadu, mosquito-induced dengue and malaria cases in the state have shown a yearly gradual decrease since 2016. TN has also reported less cases of these vector-borne diseases compared to states like Chhattisgarh, Maharashtra, Odisha, Uttar Pradesh and Gujarat among others. The data was revealed by the Union Ministry of Health after a question posed in the Lok Sabha.
According to the data, the state had recorded 4341 malaria cases in 2016, which rose to 5444 in 2017, then fell to 3758 in 2018 and 2088 in 2019, and finally 891 in 2020.
Similarly, from 2,531 dengue cases in 2016, it rose to 23,294 in 2017 and declined to 4,486 in 2018, 8,527 in 2019, and 2,410 in 2020.
The state has fared much better in controlling these vector-borne diseases compared to other states like Uttar Pradesh that recorded 24,423 cases in 2020, while West Bengal recorded 14,057 cases. Similarly, Odisha had recorded 41,738 cases, Chhattisgarh recorded 36,459 cases, while Maharashtra recorded 12,916 cases.
Reacting to the data, officials from the health department said the respective civic bodies generally begin vector control measures much ahead of the monsoon.
"In Chennai, field staff are doing door-to-door inspection to identify stored water remaining unused. They also spray larvicide regularly during the field survey," an official with the health department said.
The civic body recently even began drone spraying of larvicide in water bodies.
'Chikungunya on the rise'
While it's a good sign that dengue and malaria cases are coming down in the state, chikungunya, another vector-borne disease, has risen rapidly. While all three are transmitted through mosquitoes, they are caused by different viruses.
In 2016, the state reported 86 cases of chikungunya, while it rose to 131 in 2017 and 284 in 2018, 623 in 2019, and 1461 in 2020. However, the cases are less compared to other states.
Infectious diseases specialist Dr. Subramanian Swaminathan said chikungunya spreads by the same mosquito causing dengue. "If you have a lot of dengue cases, chikungunya spread is inevitable. We have to go against the same vector if we have to protect ourselves against the virus," he said.
"Since chikungunya is slowly increasing in number, we need to look at vector control aggressively. The virus can cause significant joint-related issues," he said, adding that there is also no great vaccine against it.
Chikungunya can also affect adults severely and society needs to practise home remedies such as closing windows and applying repellants, he added.