Is COVID vaccine effective against Omicron variant?

A three doses course of AstraZeneca's of COVID-19 vaccine is effective against the Omicron variant of coronavirus. The government and doctors are agree to this statement but people have to wear masks and make social distancing to stop the omicron because it increasing by every passing day and if one more time lockdown happens it will be difficult for people to survive let's hope the cases of omicron should Stop or minimise.