Two teams tested two of the new variants against blood taken from people who received the full dose of two doses of the Moderna or Pfizer vaccine.
While the mutations in the new variants of the virus – one first seen in Britain and another first identified in South Africa – have allowed them to evade the immunity caused by vaccination, the two teams were reported separately.
A team led by dr. Michel Nussenzweig of Rockefeller University tested plasma taken from 20 people who received two doses of the Pfizer / BioNTech or Moderna vaccine as part of clinical trials.
They found that the vaccines produce strong antibody responses, as well as cells that continuously produce new antibodies for months or years. “We measured their antibody responses to the wild-type virus. Then we took their plasmas and measured the variants,” Nussenzweig told CNN.
Wild-type virus is the catch name for virus that is usually widespread and not changed enough to be designated as variant.
“If you combine all these mixtures of antibodies, it means that they can look after the variants together,” Nussenzweig said. Although it had a diminishing effect, the response was generally so overwhelming that it should not matter, he said.
“What we really want to do with these vaccines is to keep people out of the hospital. They will probably do it regardless,” Nussenzweig added.
Eventually, the vaccines need to be updated – but the new mRNA vaccines made by Pfizer and Moderna can be changed very quickly. “Should the vaccines be adjusted?” he asked. “Probably – but that does not mean they will not be effective.”
“Further data are needed to monitor the efficacy of the Pfizer-BioNTech COVID-19 vaccine to prevent COVID-19 caused by new virus variants,” the companies said in a joint statement.
For COVID-19 vaccines, it has not yet been determined which reduction in neutralization may indicate the need for a change in vaccine strain. Should a change in vaccine strain be needed to address virus variants in the future, the companies believe that the flexibility of BioNTech’s own mRNA vaccine platform is well suited to enable such adaptation. ‘
Both the Moderna and Pfizer vaccines are designed to adapt quickly and easily.
The coronavirus is constantly mutating, like many other viruses. Compared to flu, the changes were slow and apparently did not affect the severity of diseases caused by infections.
But at least two of the variants – one first seen in Britain and known as B.1.1.7 and another first spotted in South Africa and also known as B.1.351 – apparently makes the virus more contagious.
Scientists rushed to see if the changes in the virus would make it susceptible to available treatments and vaccine.
Earlier this week, Penny Moore, associate professor at the National Institute of Communicable Diseases in South Africa, published another pre-print study showing that people who have recovered from a wild-type coronavirus infection may be a little more susceptible to B.1.135 .
They tested antibody-rich blood serum from 44 people who survived coronavirus infections before September. Half of the people showed an antibody response that might not be expected to fight the variant.
Nussenzweig said this is not surprising.
“A small difference in plasma neutralizing activity is something we need to pay attention to, but it is not a cause for concern,” he said.
“There’s a huge variety in the answers people get,” he added. “You do not have to have an immune deficiency and you still can not create a good response to this virus. People’s immune systems are as diverse as any human trait – for example beauty, intelligence, hair color, how long you are. Immune system is not otherwise. ‘
Nussenzweig said the experiments of his team suggest that it may be weaker immune responses that give rise to the coronavirus variants. The longer someone is infected, the greater the chance that the virus that infects them can mutate.
“The antibodies can opt for these variants,” he said.
If a microbe is not completely thwarted by the immune response, the variations that best resist the immune response are those that survive.
“If people give a suboptimal response, they can choose these variants,” Nussenzweig said.
This is why scientists say that it is important to get as many people vaccinated as quickly as possible so that the virus stops circulating and thus stops mutating.
Nussenzweig said his experiments so far suggest that the immune response to vaccination is many times broader and stronger than what would be needed to control the virus.