Increasing gap between shots makes vaccine more effective: Prof Karim

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Member of the Vaccine Committee for the World Health Organisation (WHO) Professor Salim Abdool Karim has weighed in on intensifying public debate on whether it’s a good idea to delay the first and second doses of the vaccine or not.

Government started the second phase of its roll-out vaccine programme on Monday, which focuses on people who are aged 60 and above, those who have underlying medical conditions as well as health care workers who were not vaccinated in the first phase of the vaccine roll-out.

Prof Karim says contrary to some people’s concerns that there’s reduced protection from one dose, the delay in administering the second dose makes the vaccine more effective.

“Where it has become clearest is for the AstraZeneca vaccine and now most recently we’ve seen some new data for the Pfizer vaccine. The recommended gap is 21 to 28 days. If you double that gap, you get a better booster. In fact, if you go even further, you get an even better boosting…” says Karim.

He adds, “Evidence is pointing to increasing the gap between the first and second and you could give more people first doses. The evidence is preliminary that you can increase the gap of the Pfizer vaccine up to three months. Even if you double the current gap, you would get a substantially improved immune-boosting response from the second dose.”

South Africa exploring the following COVID-19 vaccines


Not enough vaccine for SA: Mkhize

Meanwhile, Health Minister Zweli Mkhize said the numbers of vaccine doses that are currently coming into South Africa will not be enough to last the next two months. He said between now and June the country should have received six million doses.

Mkhize said the government was trying to get more vaccines but because of the delays, the deliveries will be received later in the year.

South Africa is hoping to vaccinate 16-million people countrywide in the second phase of the COVID-19 vaccination programme.

Mkhize explains the process of receiving the Pfizer vaccine: