CHENNAI: Meanwhile, fresh cases crossed the 400-mark after February 27 when cases were on the decline after the Omicron-fuelled third wave. Director of public health Dr T S Selvavinayagam said this time BA4 and BA5 variants are causing the surge. "The only way to stop the spread is by wearing masks and maintaining social distancing. Senior citizens and people with comorbid conditions must get themselves vaccinated adequately," he said.
The surge has pushed up the positivity rate in many districts. While the percentage of patients admitted to hospitals is low, experts say there may be an increase in absolute numbers. An increase in infections, according to National Institute of Epidemiology deputy director Dr Prabhdeep Kaur, will give the virus a chance to mutate so it can adapt itself to the new host. New mutations can be challenging because they can make vaccinations redundant.
