On October 4, EU's drug watchdog approved booster shots of the Pfizer/BioNTech Covid-19 vaccine for all people aged 18 and over. Amsterdam-based European Medicines Agency (EMA) approved extra shots of both the Moderna and Pfizer vaccines for people with severely weakened immune systems. “The risk of inflammatory heart conditions or other very rare side effects after a booster is not known and is being carefully monitored” EMA said in a statement. EMA gave a nod to people with \"severely weakened immune systems\" to get extra doses of Moderna and Pfizer at least 28 days after their second dose. Watch the video to know more.