Brussels, Nov 25 : The European Union's (EU) medicines regulator urged Europe to prepare for a new wave of the Covid pandemic as "cold winter months" arrive. "Over the last weeks we have not seen a major increase in Covid-19 case rates in the EU as a result of rising immunity following vaccinations and natural infections," Marco Cavaleri, head of Health Threats and Vaccines Strategy of the European Medicines Agency (EMA), told a press briefing. "However, this could change rapidly as we are getting into the cold winter months," Cavaleri said. "This virus is maintaining a fast pace in its evolution and new subvariants of Omicron such as BQ.1.1 and its offsprings are on the rise and replacing Omicron BA.5." These strains show "an increased propensity for immune evasion and growth advantage", he noted, expressing concern that new subvariants like BQ.1.1 are "escaping neutralisation by the currently available monoclonal antibody products, which is expected to translate into poor clinical efficacy". Vaccine booster uptake in the last few months has been "rather disappointing", with the European average rate at only 29 per cent in people at highest risk, including those aged above 60 with chronic conditions and immunocompromised, he said. It is of concern that those most at risk of hospitalization or severe Covid-19 are not adequately protected, he said, calling for more efforts to increase the revaccination rate of vulnerable groups to avoid rising hospitalization in the coming months. "The risk of severe Covid increases exponentially with age above 60. The older you are, the more you are at risk and vaccines can save your life," he added. EMA Chief Medical Officer Steffen Thirstrup told the press briefing that there are still "a lot of circulating viruses out there", and their potential to spread, especially among unvaccinated vulnerable people, is still large. "So I will still consider the pandemic being on," said Thirstrup, stressing the importance of vaccination and revaccination, particularly for vulnerable groups. /IANS