On the BBC’s Today programme this week, Sajid Javid was correct to say that prior to the vaccinations, 25,000 Covid cases a day were giving rise to about 500 deaths (Report, 6 July). But his claim that the ratio is now only one-thirtieth of that was entirely disingenuous.
It is true that the current moving averages of 25,447 daily cases and 18.14 deaths reduces the apparent ratio to about one-thirtieth of what it was. But this fails to recognise that there is a delay between infection and death. And the current 18 deaths result from cases reported 16 days ago, when they were running at 9,109. So the incidence of deaths to infections is not reduced to one-thirtieth of what it was, but only to one-eighth. And the difference between the two, in terms of fatalities, is huge.
Deaths are at roughly two per 1,000 infections. So at 100,000 by mid-August, this could mean 200 per day. And doubling every nine days, they will almost certainly go well beyond that, which could mean at least 25,000 deaths before Christmas and possibly more – skewed as ever to the old, the poor and the infirm. And this says nothing about the potential damage to the health of the survivors in aggravating conditions like diabetes and long Covid.
It is monstrously unfair to at-risk groups that masks will not be mandatory on public transport and in closed public spaces. If anyone wants to go to a nightclub unmasked, that’s fine by me – I shan’t be joining them. But two things that most people have to do are a) travel to work, and b) buy food. And they have the right to do those things in an atmosphere as free as possible of other people’s exhaled droplets.
• New strains of Covid mainly appear by random mutation. The rate at which new strains appear is directly proportional to the number of people infected. Only strains that are more transmissible than current strains will spread; those that are less transmissible cannot compete with current strains. If you halve the number of people infected, it will take twice as long for a more transmissible strain to appear. If you reduce infections by 90%, it will take 10 times as long.
More transmissible strains always increase the level of herd immunity needed to achieve control. If you drop all restrictions of control of Covid on 19 July, then you will increase the rate of emergence of new strains, and set the UK up for a perfect winter of discontent.
Prof Andrew Dobson
Department of ecology and evolutionary biology, Princeton University, New Jersey, US
• Since January, I have been volunteering as a Covid-19 vaccinator and have vaccinated more than 2,000 people in primary healthcare centres, pharmacies and NHS sites across London and the south-east. Now that the health secretary proposes to make face masks a matter of personal choice, I am left wondering whether vaccination centres will continue to be safe to attend for people who are unvaccinated or only partly vaccinated. What about healthcare workers such as myself, who without the use of face masks will face an increased risk of contracting or transmitting Covid?
Sajid Javid will need support from me and thousands of volunteers to vaccinate the remaining 50% of the population. To do this, he needs to at least mandate the use of face masks in vaccination centres.
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