A team of local experts are conducting studies to find out whether Kenyans who have received the two doses of Astrazeneca vaccine will require a third booster dose.
The team led by senior virologist Omu Anzala will be studying individuals who have received the jab over a period of time able to tell what kind of immune response is happening, how much antibody they are generating and how long those antibodies last.
A recent study by Oxford University had found that a third dose given more than six months after the second dose leads to a substantial increase in antibodies and induces a strong boost to immune response against SARS-CoV-2, including variants.
But the experts led by Anzala argue that the decision on whether there will be need for a booster dose will be based on evidence from locally generated data.
“A booster is not a bad thing. The issue is that once you have been given a vaccine, with time the immune response goes down, we will study how far down it goes because we have a threshold within which you are protected,” the medic said.
“So if we see that in a large population of people the immune system is going below that threshold in a given period of time, then we recommend a booster. It is not only the antibodies, there are other protective mechanisms that we look at, the antibodies might be low but those other protective mechanisms are high,” he added.
As at Saturday, 452,718 people had received their second dose in the country while 1,016,190 had received one dose.
This means the proportion of Kenya’s adult population that has been fully vaccinated is 1.74 per cent.
To attain herd immunity the country is required to reach at least 60 per cent of the population.
The uptake of the second dose among the priority groups shows that 90,214 healthcare workers have received their two doses, 61,688 teachers, 34,465 security officers, 140,779 people aged above 58 years and above and 125,572 members of the public.
“What we know now is that we need two doses for AZ and then after that we begin to look at the individuals over a prolonged period of time and that is what we are actually doing here,” Anzala said.
He added, “We want to be led by our own evidence, that way, we can be able to say in Kenya we need a booster every three or four years but that will only happen after we monitor those vaccinated to understand what is happening with the immune system.”