A new Covid-19 variant, the Omicron, has put countries on alert, with many announcing travel bans and mandatory quarantines. Masks, physical distancing, hygiene, and avoiding crowds should help, but we must study the behaviour of the variant to model our public health response--if it leads to a mild infection, we should prepare for home care, and if it is found to more virulent, we must gear up our hospital facilities, he adds. The current mRNA vaccines and virus-vector vaccines focus almost exclusively on the spike protein, and if the mutations make the virus unrecognisable to the vaccine-induced antibodies, the initial defence could break down, he says, adding that inactivated virus vaccines like Covaxin may be safer to depend upon in the long run.