Union health secretary, Rajesh Bhushan in a letter to Tamil Nadu chief secretary, V. Irai Anbu on Sunday called upon the state government to take immediate measures including preventing crowds and intermingling of people, increased and widespread testing, prompt tracing, and increasing vaccination coverage. 

The communique from the union health secretary is following the detection of Delta plus variants in nine samples taken from districts of Chennai, Kancheepuram, and Madurai districts of Tamil Nadu. 

The union health secretary mentioned that INSACOG - a consortium of laboratories for whole genome sequencing - has informed that the Delta plus has the characteristics of increased transmissibility, stronger binding to receptors of lung cells and potential reduction in monoclonal antibody response. 

Rajesh Bhushan in the letter also said that public health response has to be more focused and stringent and has requested the state government to ensure that adequate samples of Covid-19 positive persons are sent with immediate effect to the INSACOG laboratories where the clinical epidemiological correlations can be established. 

The Tamil Nadu government has of late increased the number of Covid testing and focused isolation of positive patients thus leading to a decrease in the number of active cases as well as fresh Covid-19 cases.