London, Nov 30 : Currently available vaccines for Covid-19 could likely be less effective against the new Omicron variant, the chief executive of US drug maker Moderna has said. According to Stephane Bancel, chief executive at Moderna, it will take several months before pharma companies can manufacture variant-specific jabs at scale, The Financial Times reported. Last week, the World Health Organisation (WHO) classified the latest variant B.1.1.529 of SARS-CoV-2 virus, with the name Omicron, as a "Variant of Concern" (VOC), which means it could be more contagious, more virulent, or more skilled at evading public health measures, vaccines and therapeutics. The variant, which contains more than 30 mutations on the spike protein that the virus uses to infect human cells, has rapidly spread in South Africa as well to various countries in Europe, including Belgium, the Netherlands, France and the UK, as well as in Asia-Pacific regions -- in Australia and Hong Kong. This suggests that the current crop of vaccines may need to be modified next year, Bancel said. "There is no world, I think, where (the effectiveness) is the same level... we had with (the) Delta (variant)," Bancel was quoted as saying to the newspaper. "I think it's going to be a material drop. I just don't know how much because we need to wait for the data. But all the scientists I've talked to... are like, 'This is not going to be good'," he added. Bancel noted that scientists were worried because 32 of the 50 mutations in the Omicron variant are on the spike protein, which current vaccines focus on to boost the human body's immune system to combat Covid. Most experts thought such a highly mutated variant would not emerge for another year or two, the report said. Meanwhile, all major drug makers including Pfizer, Moderna, Johnson and Johnson, and AstraZeneca have said that they are working to quickly investigate and adapt their shots to a new and highly mutated strain of the virus. According to the WHO, Omicron poses a "very high risk". The global health body said that scientists all over the world are working to understand Omicron, its risks and whether it causes severe disease, and vaccine effectiveness. The data will be available within two weeks. However, Bancel said it would take several months before an Omicron-specific vaccine could be produced at scale, and suggested there might be a case for giving more potent boosters to the elderly or people with compromised immune systems in the meantime. "(Moderna) and Pfizer cannot get a billion doses next week. The maths doesn't work. But could we get the billion doses out by the summer? Sure," said Bancel, who predicted Moderna could make a total of 2bn-3bn doses in 2022. But he said it would be risky to shift Moderna's entire production capacity to an Omicron-targeted jab at a time when other variants were still in circulation. /IANS