US Coronavirus: Is a booster shot necessary with the Moderna vaccine?
The FDA and CDC have already dismissed a request from Pfizer to approve a supplementary shot, but the Moderna co-founder has admitted that boosters may be needed.
As the Delta variant continues to spread across the United States there is concern that a booster shot may be needed to protect people from the more infectious strain of covid-19.
Other manufacturers have already begun to petition the Food and Drug Administration (FDA) to approve their own supplementary doses, and the co-founder of Moderna has said that he believes that the need for a booster is inevitable.
Stem cell biologist and Moderna co-founder Derrick Rossi told Canadian news channel CTV: "I think boosters are most likely going to be on the cards and evidence is pointing towards that so this is the evidence emerging out of Israel that a booster is almost certainly the way.”
Why are covid-19 booster shots necessary?
The evidence Rossi was referring to was a study carried out by the Israeli government which found that existing vaccines are much less effective against the Delta variant than they are against other strains.
On Monday Israeli officials released a statement claiming that the Pfizer-BioNTech vaccine offers just 64% protection against the Delta variant, significantly lower than the 95% coverage that was initially reported. The Moderna and the Pfizer-BioNTech vaccinations were both developed using the same mRNA technology, suggesting that Moderna may suffer a similar drop-off against the Delta strain.
"With an endemic virus, it might not be surprising that we need a booster shot every year," Rossi admitted. "Immune systems do what they do, they're great at it in the short term, but immunity does diminish with time, and especially with the emergence of more transmissible and potentially more deadly variants."
Pfizer calls for booster shot authorisation
Following on from a number of studies which have shown the Delta variant to be more resistant to vaccinations than previous strains of covid-19, drug manufacturer Pfizer has requested that health regulators consider granting emergency approval.
Pfizer is expected to publish data imminently relating to the effectiveness of the third dose of a vaccine. The official request will go to the FDA, as well as the European Medicines Agency and other international regulators.
The Pfizer statement released on Thursday read: “While protection against severe disease remained high across the full six months, a decline in efficacy against symptomatic disease over time and the continued emergence of variants are expected.
“Based on the totality of the data they have to date, Pfizer and BioNTech believe that a third dose may be beneficial within 6 to 12 months following the second dose to maintain highest levels of protection."
However in response the FDA and Centers for Disease and Control released a joint statement denying that there was any need for additional shots yet: "Americans who have been fully vaccinated do not need a booster shot at this time.”