The requirement of a booster shot for the Covid-19 vaccine, within eight to 12 months after the second shot and reiterated by the CEOs of Pfizer and Moderna late last week, illustrates yet again the long drawn-out battle against the pandemic. Countries including the US and Qatar had started the vaccination programme in December 2020. Pfizer CEO Albert Bourla cited data to support the need for a booster and explained that those who received the vaccinations in the initial stage could need a booster as soon as September or October. Recalling that the US had vaccinated people at highest risks (elderly, healthcare workers) in December/January, Moderna CEO Stéphane Bancel suggested a September start for them.
The theory is also supported by US President Joe Biden’s chief medical adviser for Covid-19, Dr Anthony Fauci, who is also the director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health in the US. “I think we will almost certainly require a booster sometime within a year or so after getting the primary [shot] because the durability of protection against coronavirus is generally not lifelong,” he told the same Axios event where the Pfizer and Moderna CEOs also participated.
As inoculations around the world continue to increase, medical experts believe coronavirus may end up being like influenza, which requires a new vaccine every year. This is because the circulating strains mutate quickly, and immunity from the vaccine soon wears off. Over in the UK, the government last week announced the launch of a new clinical trial looking specifically into booster shots.  The trial, led by the University Hospital Southampton NHS Foundation Trust, will study the impact of seven different Covid-19 vaccines when given as a third dose. Researchers at the US Centers for Disease Control and Prevention are already looking into whether a booster specific to variants that are already in the US will be needed as well, if protection against the virus fades over time.
However, Dr Fauci is of the view that such variant-specific boosters may not be needed. “Instead of having to play whack-a-mole with each individual variant and develop a booster that’s variant-specific, it is likely that you could just keep boosting against the wild type, and wind up getting a good enough response that you wouldn’t have to worry about the variants,” he said. The World Health Organisation’s (WHO) regional director for Europe, Dr Hans Henri P Kluge, said that all current approved Covid-19 vaccines are effective against all known variants of the virus.
The need for an annual booster shot might become a minor inconvenience in rich countries, but it could become a serious problem in the developing world. Gavi, the vaccine alliance, is hoping that shots distributed through the vaccine-sharing initiative known as Covax will reach 27% of the populations of lower-income countries this year. But the scheme is already facing shortages, because of a lack of supplies caused by increased demand in India, home to the Serum Institute of India (SII) the world’s largest vaccine manufacturer. SII, the main supplier of Covid-19 vaccine doses to the UN-backed Covax scheme, said last week that it hopes to start delivering doses to Covax and to other countries by the end of the year. The WHO, which co-leads Covax, has urged vaccine makers outside India to advance supplies to the programme.
Related Story