Given that COVID-19 vaccinations were only recently approved for emergency use, doctors are actively researching vaccinated persons to see when their protection wears off.
The effectiveness of the vaccines against new coronavirus variations will also determine whether, when, and how often additional doses are required.
“We only have data for as long as vaccines have been examined,” Deborah Fuller, a vaccine researcher at the University of Washington, explained.
We need to look into the vaccinated population and discover when people become vulnerable to the virus again.
Pfizer’s two-dose vaccine appears to be extremely successful for at least six months, if not longer, according to the continuing experiment. On April 1, Pfizer CEO Albert Bourla stated that people will “likely” require a third booster dose over the next 12 months, and that annual doses may be required.
Initial evidence also suggests that Moderna vaccinations retain the majority of their potency for at least six months, however the exact length of time is unknown. According to the business, immunity should last at least a year.
Antibodies, on the other hand, don’t give the complete tale. Our immune systems have another line of defense called B and T cells to fight off intruders like viruses, and some of these cells can survive long after antibody levels have dwindled. If they come across the same virus again in the future, those battle-tested cells may be able to respond more quickly.
Even if they don’t completely prevent illness, they may be able to lessen its severity. But it’s unclear what role – and for how long – such “memory” cells might play with the coronavirus.
Even if the protection lasts far longer than six months or a year, researchers say that fast spreading coronavirus variations and others that may emerge could necessitate recurring booster shots akin to annual flu shots.
So far, the vaccinations appear to be effective against the most notable variations that have appeared, though not so much against the one discovered in South Africa.
Singapore announced on Thursday (April 22) that “further rounds of vaccination may be required even beyond this year to potentially deal with emerging strains of the virus.”
It also intends to provide recovered migrant workers a single COVID-19 vaccine booster dose.
The US announced earlier this month that it is preparing for the prospect of a booster shot between nine and 12 months after patients are first vaccinated against COVID-19.
If it is discovered that patients require another injection, a single dose could provide additional protection or contain immunization for one or multiple variations.
The need for follow-up vaccinations will be determined in part by the efficacy of the worldwide immunization campaign and the virus’s and new variants’ spread.