Research suggests that the Delta variant is both highly transmissible and partly resistant to current vaccines, prompting calls for extra measures.
Governments should consider offering another COVID vaccine specifically tailored to the Delta variant, according to a U.K. government advisor and Delta researcher. The guidance comes after a new study indicated that the Delta variant was eight times less sensitive to the antibodies that vaccines provide to people compared to an earlier version of COVID from April 2020, in a lab environment. This means it would take more antibodies from a vaccinated person to block Delta than to block this earlier version of the virus. According to an early manuscript of the study available online, it also found that Delta was resistant to antibodies from people who had COVID before. It found that Delta was 5.7 times less sensitive to antibodies produced by recovered patients than the April 2020 version of COVID, referred to as a „wild type (WT) Wuhan-1“ variant. „We should seriously consider Delta-specific vaccines,“ said professor Ravi Gupta, professor of clinical microbiology at Cambridge University, member of the U.K. government’s New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) virus advisory group, and lead author of the study. „The infectivity enhancement likely explains a lot of the vaccine breakthrough that we see.“ Indeed, breakthrough cases have captured numerous headlines this year amid reports of people getting infected with COVID despite being fully vaccinated. Breakthrough cases are expected with any vaccine, though some COVID variants are thought to pose extra resistance to immunity compared to others.
