A study reveals the effect of increasing the time between two doses of the Pfizer vaccine

Follow Up - INA

A British study, whose results were published on Friday, revealed the effect of increasing the interval between two doses of the Pfizer anti-Corona vaccine on antibody levels .

According to the study, the longer interval between the two doses of the Covid-19 vaccine produced by Pfizer, leads to  an increase in total levels of antibodies compared to the shorter gap .

This study may help guide vaccination strategies against the mutated strain "Delta" that reduce the effectiveness of the first dose of the Covid-19 vaccine, although the two doses are still protective .

For the longer interval between the two doses, the levels of inhibitory antibodies against the delta mutated strain were poorly induced after one dose and were not maintained during the period before the second dose, " said the authors of the Oxford-led study .

"After two doses of the vaccine, the levels of inhibitory antibodies were twice as high after the longer interval compared to the shorter period between the two doses," they added.

It is believed that inhibitory antibodies play an important role in immunity against the Corona virus, but not as a whole, as T cells play a role as well .

The study found that total T-cell levels were 1.6 times lower with the long interval than with the short-interval dosing schedule of 3 to 4 weeks, but the proportion of "helper" T cells  that support long-term immune memory was higher with the long interval. .

The study authors emphasized that any schedule of the two doses results in a strong response with regard to antibodies and T cells in the study of 503 health care workers .

These announced findings support the view that while a second dose is needed to provide complete protection against the delta mutated strain, delaying that dose may provide more sustained immunity even if at the expense of short-term protection .

Last December, Britain extended the interval between the two vaccine doses to 12 weeks, although Pfizer warned that there was no evidence to support an increase in the interval of more than three weeks .

Britain currently recommends an 8-week interval between the two vaccine doses to give more people high protection against the delta mutated strain more quickly while continuing to increase the immune response in the long term .

Source: Sky News