The spread of the Delta variant has led some experts to believe a mRNA booster (by Pfizer or Moderna) may be needed for the J&J vaccine. It has also been identified in more than 85 countries and has started to dominate third wave Covid-19 infections in South Africa. But Professor Linda-Gail Bekker, co-lead investigator of the J&J Sisonke study in SA, said that recommending booster top-ups with another vaccine is premature. The SAMRC release indicated that of healthcare workers who had "breakthrough" Covid-19 infections, 94% were mild, 4% moderate and only 2% severe. READ | Covid-19 vaccines and the Delta variant: What we know

Source: News 24 July 05, 2021 02:48 UTC