Kenya received 1.02M AstraZeneca vaccine doses. So how does it work?

AstraZeneca’s vaccine, made with a team at Britain’s University of Oxford, is, like Janssen’s, a vector vaccine.

It uses an adenovirus that infects chimpanzees, but doesn’t make people sick, to carry the spike protein from the coronavirus into cells.

It was modified so that it doesn’t replicate itself, then genetically engineered to inject cells with the DNA encoding for the full coronavirus spike protein.

It’s a cheaper way to make vaccines — but slower than using ribonucleic acid (RNA).

The company has pledged to make its vaccine available inexpensively to countries around the world.

The vaccine can be kept stable for six months at standard refrigerator temperatures, the company said.

It’s approved in Britain but the US FDA is waiting for data from US trials.

Data released from trials in Britain, South Africa and Brazil in a Lancet preprint indicates it is about 67% effective at preventing symptomatic infection two weeks after two doses.

But the Oxford team also tested some volunteers to see if they became infected at all, and said they think the vaccine prevents infections in general.

Plus, the studies indicated a single dose of vaccine prevented 76% of symptomatic infections for up to 90 days, and if more time passed between the first and second doses, the efficacy improved.

When volunteers waited 12 weeks between doses, the vaccine’s efficacy went up to 82%.

A longer wait between doses would help get more people vaccinated, since the companies are struggling to keep up with demand.

Kenya decided to go ahead with its plan to inoculate its citizens against COVID-19 using AstraZeneca vaccine, dismissing concerns over its efficacy.

South Africa paused the rollout of the vaccine developed by AstraZeneca and Oxford University following a small clinical trial that showed it offered minimal protection against mild to moderate illness from the 501Y.V2 variant dominant in the country.

That move will not deter Kenya, which received 1.02 million doses of the vaccine on Tuesday.

“We are going to continue with AstraZeneca because we are doing our own sequencing and we are comfortable to move forward with it,” Health CS Mercy Mwangangi told Reuters.

The World Heath Organisation also issued an advisory telling countries to continue using the vaccine, she said, which further supports the Kenyan government’s position.

Report by CNN and Reuters