New Delhi, Nov 27 : The currently available vaccines against Covid-19 appear to be effective against the newly detected omicron Covid variant, South Africa's health minister has said. The new variant, known as B.1.1.529, has been detected in small numbers in South Africa. The World Health Organization (WHO) on Friday assigned the Greek letter Omicron to the variant. According to South African Health Minister Joe Phaahla, vaccines are still effective in preventing severe Covid from the variant, CNBC reported. Phaahla added that the Omicron variant may be more transmissible due to its genetic composition. Meanwhile, world's major manufacturers of Covid-19 vaccines said Friday that they are working to quickly investigate and adapt their shots to a new and highly mutated strain of the virus. The WHO said the new strain may pose a higher risk of re-infection than past mutations of the virus. Pfizer and BioNTech said they are investigating the new, heavily mutated variant, the report said. The companies said they can adapt their mRNA vaccine within six weeks and start shipping batches within 100 days if an escape variant is identified. Moderna, Johnson & Johnson and AstraZeneca have also stated that they are investigating and testing the new variant. Moderna said it will test three booster candidates against omicron, including at a higher dosage level. The company will also develop a booster dose specific to the variant, it said in a statement. The variant, which emerged in South Africa, has about 50 mutations, more than 30 of which are on the spike protein that allows the virus to bind to human cells. While the spread of the new variant is still in its early stages, it's not yet clear how severe an infection would be to a vaccinated person. /IANS