A woman reacts as she receives the Johnson & Johnson vaccine against coronavirus disease (COVID-19) as part of a government plan to vaccinate Mexican border residents on the common border with the United States in Tijuana, Mexico, June 17, 2021 .

Jorge Duenes | Reuters

Some countries, like the US and UK, have already signaled that they could introduce Covid-19 booster vaccinations within a year. Now pressure is mounting on governments to mobilize refresher programs – not an easy task given the ongoing uncertainties surrounding the pandemic, vaccines and variants.

However, there are no concrete plans for Covid-19 booster vaccinations. Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said last month it was “just something we need to find out over time.”

As the talk of booster shots increases, so far we know this:

What?

First off, there are question marks as to whether we actually need a third dose of a Covid-19 vaccine as we don’t know how long the immunity is currently lasting.

The US and UK use vaccines from Pfizer-BioNTech, Moderna and Johnson & Johnson, with the UK also relying heavily on AstraZeneca-Oxford University vaccine.

There are also unknowns as to whether people should receive a booster vaccine that is identical to the vaccines they originally had. And also whether the vaccinations have to be adapted to variants, similar to the flu vaccine, or whether they can stay as they are.

When?

How?

Experts argue that any booster program requires extensive planning to help health services deal with it. This is especially important as not only are they under pressure from running current vaccination programs, but they also care for the health needs of patients whose procedures and treatments have been delayed due to the coronavirus pandemic.

In the UK, the chairman of the Royal College of General Practitioners, Martin Marshall, told the BBC radio program “Today” that the UK’s National Health Service needs to know what it will do in the fall.

“First of all, we need to know if a booster program is needed … who needs it, such as the more vulnerable and the elderly. We need to know where to get it. ” [the booster shots] and by whom, “he said on Monday.

“Our general practitioners and nurses are very busy, so is it possible for a booster to be carried out by non-clinically trained vaccination staff?” He asked, pleading for a booster vaccination alongside the winter flu vaccination.

On the same radio broadcast, Anthony Harnden, vice-chairman of the Joint Vaccination and Immunization Committee (which advises the UK government on vaccination policy) warned that careful consideration should be given to who a refresher campaign is targeting.

He said priority needs are “data driven” despite recognizing the need for the NHS to plan ahead.

moral

There is a moral argument about whether booster vaccination programs are the right thing to do when many less developed countries are lagging behind on their vaccination programs.

The World Health Organization has urged richer countries to donate vaccines to poorer ones before they consider booster vaccinations. In fact, the jury at the WHO is on whether a booster vaccination is needed at all.

“We don’t have the information needed to make a recommendation on whether or not a booster is needed,” World Health Organization chief scientist Soumya Swaminathan said in a Zoom call on Friday, Bloomberg reported, adding that it was the “science still evolving”. . “

Delta variant

WHO officials also said last week that there were reports that the Delta variant caused more severe symptoms, but that additional research was needed to confirm those conclusions. However, there is evidence that the Delta strain may cause different symptoms than other variants.

So far, the vaccines have proven to be resistant to new variants and remain largely effective in preventing serious Covid-19 for fully vaccinated people. An analysis published by Public Health England last Monday found that two doses of the Pfizer BioNTech or AstraZeneca Covid-19 vaccines were highly effective against hospitalizations from the Delta variant.

On Friday, WHO’s Swaminathan said scientists needed more data on the variant, including how it affects the effectiveness of Covid-19 vaccines.

“How many become infected and how many of them are hospitalized and seriously ill?” said Swaminathan on Friday. “That is something that we are watching very closely.”

– CNBC’s Berkeley Lovelace Jr. contributed to coverage of this story.

Correction: This article has been updated to reflect that just over 55% of adults in the US are fully vaccinated against Covid-19.