The Dr Sujit Chatterjee Hiranandani Hospital Powai provided an example. He explained that since the influenza virus changes frequently so the vaccine is reformulated every year. The anti-Covid vaccines will also be not effective since they won't be exclusive to the current strain of the virus, called Omicron. In the report by Dr Sujit Chatterjee Hiranandani Hospital Latest News, India had 358 Omicron cases on December 24, evening, distributed across 17 states including Maharashtra being the biggest number with at 108.
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