A recent study by 500-odd healthcare workers revealed that longer gap in Pfizer-BioNTech Covid-19 vaccines can result in higher level of antibodies after the second dose. This will lead to a stronger immunity against the Delta variant and all other variants. This is because, as longer gaps are kept between the first and second doses, the vaccine generates strong antibody and T cell immune responses. However, the level of antibodies may drop significantly in between the doses.
The study was undertaken by UK researchers of the University of Oxford, and Universities of Birmingham, Newcastle, Liverpool and Sheffield. It was supported by the UK Coronavirus Immunology Consortium and is, by far, one of the most in-depth studies on the immune response generated by Pfizer. However, all the studies showed that, both short and long dosing schedules facilitate strong protection against Covid-19. It thus underscores the need to take the second dose of the vaccine, especially against the Delta variant.
The study by the UK Researchers also found that, the levels of T cell, which is an immune cell, were 1.6 times lower with a long gap as against the short dosing schedule of 3-4 weeks. However, it was the ‘helper’ T cells that were found in higher proportion with a long gap. It also revealed that after both the doses of the vaccine, neutralising antibody levels were twice as high after the long dosing interval compared to the shorter dosing interval.
Regardless of the dosing schedule, one’s genetics, underlying health conditions and past exposure to Covid-19 and other viruses may determine the levels of antibodies and T cells in his/her body as well.