Half Of UK Won’t Be Protected Against Covid-19 When Lockdown Is Lifted
At least 51.2% of the UK population will not be protected against Covid-19 when lockdown measures are lifted on 21 June according to new research.
The UK’s Prime Minister Boris Johnson announced on Monday that on 21 June the country is due to exit its lockdown which has been in place since 4 January. He boasted that the driving force behind this has been the rapid progress of the UK’s vaccine programme which has seen nearly 20 million doses given out since the first person was vaccinated on 8 December.
The programme is controversial as it involves the second dose of Pfizer’s vaccine being given 12 weeks after the first against the manufacturer’s instructions. Pfizer has stressed that the limit should be six weeks at most as it has no data on the efficacy of its vaccine after that.
Increasing the gap between the doses has enabled the government to vaccinate more people in a shorter period of time but it remains to be seen whether this will be effective enough to combat the spread of Covid-19 as the British Medical Journal reported that one dose of Pfizer’s vaccine only gives 52% protection.
The government has partly justified its strategy by pointing out that it is also using the vaccine developed by Astrazeneca and Oxford University which have tested it with a 12-week gap between doses. The tests show that two doses of the vaccine give 82.4% protection with that level reducing to 76% for just one.
Whilst the government has made no secret about the efficacy of the vaccines, no one has revealed how many people are expected to be protected by them when lockdown is lifted. Until now.
The conclusion is derived entirely from data supplied directly by the government with the starting point being the number of vaccinations so far. The government’s data shows that yesterday (23 February 2021), 192,341 first doses of the vaccine were given bringing the total to 17,916,181. Second doses lag far behind as only 642,788 have been given so far with yesterday’s tally only coming to 18,463. The key metrics are the averages over the seven days to 23 February which are as follows:
First doses daily average: 334,296
Second doses daily average: 13,803
Total doses daily average: 348,099
To forecast the course of the vaccination programme, these averages need to be multiplied by the number of days in the periods between key thresholds. The dates are determined by the government’s 12-week deadline for giving the second dose of the vaccine. The very first dose was given on 8 December and 12 weeks after that is 2 March which is 7 days from now. So, based on the average daily doses, over the next 7 days another 2,340,072 first doses will be given to people along with 96,621 second doses. This will yield the following totals by 2 March:
First doses: 20,256,253 (17,916,181 + 2,340,072)
Second doses: 739,409 (642,788 + 96,621)
Soon after that, there will need to be a sharp increase in the number of second doses given to people. Over the 33 days from 8 December to 10 January 2,286,572 first doses were given out so second doses for them will all need to be given at the latest 12 weeks later during the 33 day period between 3 March and 4 April. As 739,409 second doses will have already been given by then, 1,547,163 will remain and they will take four days to clear at the average daily rate of 348,099. This leaves 29 days for more doses to be given over the period between 3 March and 4 April. There are three scenarios which will determine the number of doses that are given out during this time.
Scenario 1. This involves only giving first doses. At the average total daily rate of 348,099 this would enable 10,094,871 first doses to be given out over the 29 days. So, by 4 April the total number of doses will be:
First doses: 30,351,124 (10,094,871 + 20,256,253)
Second doses: 2,286,572 (739,409 + 1,547,163)
Scenario 2. This involves giving out first and second doses in the same way that the government has done so far. This would mean that over the 29 days between 7 March and 4 April, 9,694,584 first doses would be given out based on the average first dose daily rate of 334,296. A total of 400,287 second doses would be given over the 29 days as the average daily rate for them is 13,803. So, by 4 April the total number of doses will be:
First doses: 29,950,837 (9,694,584 + 20,256,253)
Second doses: 2,686,859 (400,287 + 739,409 + 1,547,163)
Scenario 3. This involves giving second doses sooner than 12 weeks after the first. At the average total daily rate of 348,099 this would enable 10,094,871 second doses to be given over the 29 days. So, by 4 April the total number of doses will be:
First doses: 20,256,253
Second doses: 12,381,443 (10,094,871 + 739,409 + 1,547,163)
It doesn’t stop there. The government has set a target of giving 32 million first doses by the end of April so what will the total be in each scenario? By 4 April the government will have cleared the second doses relating to ones which were first given between 8 December and 10 January. The next period correlates to the 26 days from 11 January to 5 February as there are 26 days from 5 April to the end of the month.
The government’s data shows that 9,178,638 first doses were given over the 26 days from 11 January to 5 February. The second doses for them will take 26 days to clear at the average total daily rate of 348,099 which means that there is no capacity to give first doses as well during that time. The exception is scenario 3 as this involved giving the second doses early which means more first doses can be given between 5 April and 30 April. By then the total number of doses will be:
Scenario 1.
First doses: 30,351,124
Second doses: 11,465,210 (9,178,638 + 2,286,572)
Scenario 2.
First doses: 29,950,837
Second doses: 11,865,497 (9,178,638 + 2,686,859)
Scenario 3.
First doses: 29,434,891 (9,178,638 + 20,256,253)
Second doses: 12,381,443
The totals above represent the situation at 30 April and clear the backlog of second doses up to 5 February. The government’s data shows that 6,450,971 first doses have been given over the 17 days since then (to 23 February). This yields a daily average of 379,469 which is higher than the average total daily rate of vaccine doses over the past seven days. So unless that sharply increases, it means that when the 379,469 second doses need to be given over the 17 days after 30 April there will be no capacity to administer any new first doses at the same time. So by 17 May the total number of doses will be:
Scenario 1.
First doses: 30,351,124
Second doses: 17,916,181 (11,465,210 + 6,450,971)
Scenario 2.
First doses: 29,950,837
Second doses: 18,316,468 (11,865,497 + 6,450,971)
Scenario 3.
First doses: 29,434,891
Second doses: 18,832,414 (12,381,443 + 6,450,971)
There are then seven days between 18 May and 24 May when 2,340,072 second doses need to be given as that is the number of first doses which are forecast to be given over the period from 24 February to 2 March. With a total capacity of 2,436,693 (348,099 x 7) doses over that time, 96,621 first doses can also be given out. So by 24 May the total number of doses will be:
Scenario 1.
First doses: 30,447,745 (30,351,124 + 96,621)
Second doses: 20,256,253 (17,916,181 + 2,340,072)
Scenario 2.
First doses: 30,047,458 (29,950,837 + 96,621)
Second doses: 20,656,540 (18,316,468 + 2,340,072)
Scenario 3.
First doses: 29,531,512 (29,434,891 + 96,621)
Second doses: 21,172,486 (18,832,414 + 2,340,072)
There will then be four days of respite from 25 May to 28 May when 348,099 daily first doses (totalling 1,392,396) could be given out. This correlates with 3 March to 6 March when second doses were given out to people who got the first ones in the very first vaccination period. So by 28 May the total number of doses will be:
Scenario 1.
First doses: 31,840,141 (30,447,745 + 1,392,396)
Second doses: 20,256,253
Scenario 2.
First doses: 31,439,854 (30,047,458 + 1,392,396)
Second doses: 20,656,540
Scenario 3.
First doses: 30,923,908 (29,531,512 + 1,392,396)
Second doses: 21,172,486
This clears the second doses up to 6 March and takes us to 29 May. The next step determines the total number of doses which will be given out by the time lockdown is lifted on 21 June and it all depends on which scenario the government takes right at the start. If the government takes scenario 1 (where 10,094,871 first doses were given out over the 29 days between 7 March to 4 April) there will be no capacity to give out new first doses over the 29 days from 29 May to 26 June. Scenario 2 is a slight improvement but scenario 3 is greatly improved as only second doses were given out between 7 March and 4 April. So by 26 June the total number of doses will be:
Scenario 1.
First doses: 31,840,141
Second doses: 30,351,124 (10,094,871 + 20,256,253)
Scenario 2.
First doses: 31,840,141 (400,287 + 31,439,854)
Second doses: 30,351,124 (9,694,584 + 20,656,540)
Scenario 3.
First doses: 41,018,779 (10,094,871 + 30,923,908)
Second doses: 21,172,486
So, five days after lockdown measures have been lifted on 21 June, how many people will be protected? The government has not disclosed whether it has given out more Pfizer or Astrazeneca vaccines though it is widely understood that the lion’s share is of the latter. This is because Astrazeneca’s vaccine is less fragile and easier to store than its counterpart. Our analysis will calculate the level of protection based on Astrazeneca’s results but not for this reason.
Using Astrazeneca’s data gives the government the greatest chance of painting a positive picture. This is because one dose of its vaccine gives 76% protection compared to 52% from Pfizer. It rises to 95% with two doses of Pfizer which is far higher than the 82.4% from Astrazeneca. However, Pfizer’s boss says he has no evidence of what, if any, protection is offered when the second dose is given more than six weeks after the first.
For all these reasons, it is fairest to use Astrazeneca’s data of 76% protection from one dose and 82.4% from two. This yields the following results for 26 June:
Scenario 1.
TOTAL FIRST DOSES: 31,840,141
PEOPLE GIVEN FIRST DOSE ONLY: 1,489,017 (1,131,653 protected and 357,364 unprotected)
PEOPLE GIVEN FIRST AND SECOND DOSES: 30,351,124 (25,009,326 protected and 5,341,798 unprotected)
PEOPLE UNVACCINATED: 34,809,859 (52.2% of UK’s 66,650,000 population)
PEOPLE VACCINATED BUT UNPROTECTED: 5,699,162 (17.9% of total)
PEOPLE UNVACCINATED OR UNPROTECTED: 40,509,021 (60.1% of UK population)
Scenario 2.
TOTAL FIRST DOSES: 31,840,141
PEOPLE GIVEN FIRST DOSE ONLY: 1,489,017 (1,131,653 protected and 357,364 unprotected)
PEOPLE GIVEN FIRST AND SECOND DOSES: 30,351,124 (25,009,326 protected and 5,341,798 unprotected)
PEOPLE UNVACCINATED: 34,809,859 (52.2% of UK’s 66,650,000 population)
PEOPLE VACCINATED BUT UNPROTECTED: 5,699,162 (17.9% of total)
PEOPLE UNVACCINATED OR UNPROTECTED: 40,509,021 (60.8% of UK population)
Scenario 3.
TOTAL FIRST DOSES: 41,018,779
PEOPLE GIVEN FIRST DOSE ONLY: 19,846,293 (15,083,183 protected and 4,763,110 unprotected)
PEOPLE GIVEN FIRST AND SECOND DOSES: 21,172,486 (17,446,128 protected and 3,726,358 unprotected)
PEOPLE UNVACCINATED: 25,631,221 (38.5% of UK’s 66,650,000 population)
PEOPLE VACCINATED BUT UNPROTECTED: 8,489,468 (20.7% of total)
PEOPLE UNVACCINATED OR UNPROTECTED: 34,120,689 (51.2% of UK population)
So, at least, 51.2% of the UK’s population will be unvaccinated or unprotected when lockdown measures end. Furthermore, 8,489,468 of the vaccinated people will actually be unprotected but won’t be aware of this. They comprise 20.7% of the total number of vaccinated people. So, put simply, one in every five people who are vaccinated aren’t actually protected.
It is hard to imagine a government allowing a plane to fly if there was a one in five chance of it crashing so why is it planning to lift the lockdown even though it has the same odds of failure? Likewise, it is hard to imagine that people would be prepared to get on a plane if there was a 20.7% of it crashing. Testimony to this, the actual risk of a plane crashing is 0.00002% (1 in 5.4 million) according to a 2015 study by The Economist.
It needs to be stressed that the actual levels of protection may be much lower than the results above as they don’t take into account the millions of people who have had the Pfizer vaccine which only gives 52% protection from one dose and an unknown level of protection from two thanks to the government’s decision to delay the second dose by 12 weeks.
The number of people who are vaccinated may also end up being higher or lower than the totals above as they are based on the average over the past seven days. However, that won’t affect the level of protection that the vaccines offer and this is the driving force behind the shocking conclusion. The government had a chance to give everyone in the UK 95% protection by sticking with the Pfizer vaccine and administering the second dose within six weeks at the latest as the manufacturer advised. It may live to regret the decision not to do this.
