Lengthy vaccination gaps ‘risky’

As the government struggles to get supplies for the second Covid-19 vaccine jab, experts are warning that the longer gap between the doses could lead to resistance to the vaccine.

There is uncertainty over the second dose of the Oxford/AstraZeneca vaccine in which 802,760 people have received the first dose.

The duration between the two doses of AstraZeneca, which is currently being administered in the country, is between four to 12 weeks and if it exceeds the 12 weeks, then the chances of the vaccine working will be weakened.

This would mean that those who had gotten their first doses either start afresh or get another vaccine.

“Taking the second dose too late is risky, because the effects of the first dose might start to weaken. But giving the second dose too soon is also risky, because your immune system needs time to fully react to the first dose so that it can then get maximum benefit from the second. In general, a 12-week gap between vaccine doses would not be long enough for that initial protection to fade,” says a research paper published last week in British Medical Journal (BMJ).

It states that when one takes long to get the second dose than the stipulated time, it would foster the emergence of new variants that could evade vaccine-induced antibodies.

India blocked exports of the AstraZeneca vaccine to balance surging domestic demand with international orders.

The ban means poorer nations, including Kenya, will probably have to wait a few months before receiving their first shots.

Delhi is currently witnessing a resurgence of infections and, as of yesterday, there were over 332,000 new active cases, which were steadily rising.