The manufacturer of the Pfizer/BioNTech vaccine has said its efficacy has only been assessed for two doses given three weeks apart. Therefore the idea that a single dose will be protective beyond three weeks is speculative (Covid vaccine: chief medical officers defend rescheduling of second doses, 31 December). It would be truly tragic to vaccinate millions of recipients with the Pfizer/ BioNTech vaccine (at considerable effort and financial cost) with a twelve-week gap between doses if this doesn’t give them protection.
It is worth noting that there is likely to be a correlation between the antibody response and protection from infection. Therefore volunteers who have already completed two doses could be asked to give a small sample of blood to check the level of neutralising antibodies present four weeks from the first dose. Recipients whose second dose has been postponed after 4 January could give a similar sample from 11 January onwards to check their levels at the four-week point. A relatively small number of volunteers (perhaps 20 or 30 in each group) might settle this.
If there is little or no discrepancy between the two groups, we could congratulate our leaders on their perspicacity, and carry on with the new dosing schedule, with further opportunities to monitor antibody levels and incidence of infection in both groups over time.
On the other hand, if a single dose fails to provoke a comparable neutralising antibody response, there would be an opportunity to return to the three-week schedule and make amends for what could otherwise turn out to be a horrific omnishambles.
Dr Grizelda George
• Quite apart from the massive administrative work facing GP surgeries because of the change in vaccine policy, there is the question of consent. After a series of questions from a doctor at my surgery, those receiving their first dose of vaccine were asked for their consent. This was given on the basis of information that a second would be given three weeks later, on a date provided. Since Pfizer/BioNTech say their data is based on a 21-day booster, who will be accountable if something goes wrong?
While I accept the premise behind the change, surely it would have been best to continue with the established second dose dates, given the current relatively small number of recipients so far? As a patient participation group member of my surgery, having seen the logistical task already involved, I cannot imagine what the staff must be feeling when already under pressure. My sympathy goes to them; it seems those at the top have little understanding of this aspect.
Lewes, East Sussex
• I can’t see how the recently adopted policy of delaying the second dose for people receiving the Covid vaccines is going to inspire people to trust the immunisation programme. On the contrary, if the government and the NHS wanted to undermine confidence in it, they probably couldn’t have done better.
People who are vulnerable or who have been shielding are not likely to feel safe, even with continued Covid-19 precautions, and may continue hiding indoors. Others may decide the vaccine isn’t worth having, or feel emboldened in spreading the message that it doesn’t work. We don’t have the certainty that frontline workers exposed to a high risk of infection will be sufficiently protected.
It looks like the situation in the NHS is now so dire that even our scientists are being panicked into not following the science.
Jenny van Tinteren