Will vaccines work against new variant?

As South Africa gears up for the first phase of Covid-19 vaccination programme, scientists have been left scratching their heads on whether the vaccines will work against the new variant of Sars-CoV-2, the virus that causes Covid-19, termed 501Y.V2.

According to the National Institute for Communicable Diseases (NICD), this new variant’s lineage has shown to predominate in the Eastern Cape, Western Cape and KwaZulu-Natal, all of which experienced major Covid-19 outbreaks.

Preliminary NICD analysis of 479 sequences from Gauteng, indicated that the new variant’s lineage first appeared in November and by December accounted for 84% (62/74) of sequences.

The Eastern Cape,

Western Cape, KwaZulu-Natal and Gauteng data suggests that the new variant’s lineage may be predominant throughout SA.

There is also the question of how SA achieve will herd immunity if the efficacy of AstraZeneca is said to be only 67%, when the goal was to get two-thirds of the population vaccinated.

Professor Koleka Mlisana, chair of the Covid-19 ministerial advisory committee laboratory testing committee and National Health Laboratory Service executive manager for research and quality assurance, said this was a great concern and that scientists were under pressure to get answers.

“The new variant is a concern… we are still trying to get a better understanding, we do not know what impact it is going to have on the vaccines but what I can assure is the fact that a lot of work is ongoing to take the current variant and test it against people who have actually been exposed to the different vaccines and see how the serums on those individuals behave with the new variant,” she said.

Mlisana said soon they have an understanding whether there will be reduced efficacy in those infected with the new variant.

“Those results will be out and everybody will be aware of them and see then how we approach this,” she said.

Mlisana was responding to questions during a webinar on Covid-19 hosted by Government Communication and Information System, department of health and the African Union yesterday.

On the argument that if AstraZeneca was only effective 67% of the time, juxtaposed by SA’s goal for herd immunity, around 45% of the population will be immune to the virus, Mlisana said the efficacy percentages were from vaccine trials.

She explained that for trials to measure efficacy, it used a certain aspect of the immune response and that there were various immune responses, including nonspecific and specific responses, antibodies and T-cells

Mlisana said once you introduce the vaccine to millions of individuals, then you are able to increase its effect.

A million doses of the Oxford University developed AstraZeneca vaccine will arrive in SA on Monday but the consignment is expected to be quarantined and reconciled for about 14 days.

The new variant is a concern