A number of posts on social media have made comparisons between the reported effectiveness of the potential Pfizer Covid-19 vaccine and reported Covid-19 recovery rate.
Text on the posts reads:
“Pfizer vaccine is 90% effective
Virus has 99.97% recovery rate
I’m not an accountant anymore but I’m pretty sure we don’t need this jab at all 💉🤮🤦🏻♀️
(or any other for that matter)”.
This post understates the death rate of Covid-19, and doesn’t take into account those who continue to suffer Covid symptoms. The comparison with the reported effectiveness of the Pfizer vaccine is misleading, as that’s looking at how many people get infected, not how many die.
The Covid-19 death rate
The posts claim that 99.94% to 99.97% of those who catch Covid-19 recover. This is incorrect.
This is likely based on estimates of how many people have died after catching Covid-19, but gives a figure for the death rate that is far too low. Additionally, it’s wrong to say that anybody who hasn’t died from Covid-19 has “recovered”, because some patients remain ill for a long time.
The figures given in the post would suggest that between 0.03% and 0.06% of people who get Covid-19 die, but this cannot be true.
Looking at England and Wales, provisional figures from the Office for National Statistics (ONS) show 53,675 deaths registered in 2020 had Covid-19 listed as the underlying cause on the death certificate, as of 6 November.
The current population estimate for England and Wales is 59.4 million, meaning that 0.09% of the total population has already died of Covid-19.
Of course, as we’ve written before, it’s not plausible that everyone in the country has already been infected, which means that the true death rate is significantly higher than this.
Scientists estimated that, until the end of June, the actual fatality rate in England was about 0.9%. That’s significantly more deadly than the post suggests.
The chances of dying if you catch Covid-19 vary a great deal according to your age and overall health, with older people and those with underlying conditions facing a much higher risk. Different countries are likely to have different death rates, depending partly on the age and health of their populations, the quality of their healthcare, and other factors that we may not yet understand.
Additionally, the death rate from the disease may be lower now, and in the future, than it was at the start of the pandemic, because of improvements in medical treatment.
“Not dead” doesn’t mean “recovered”
“Recovered” from Covid-19 implies someone who has caught the disease returning to their original state of health. We are becoming more aware that many people who catch Covid-19 continue to suffer long term health problems, known as “long Covid”.
One NHS report suggested that up to 45% of those admitted to hospital with Covid up until 5 June 2020 would need “ongoing support”. The length of this ongoing support varies—1 in 20 people who get Covid are reported to have symptoms for more than eight weeks. However, longer term effects are currently still relatively unknown.
How effective is the Pfizer vaccine?
The reported effectiveness of the Pfizer vaccine is also potentially subject to change.
The Pfizer vaccine is currently reported to be at least 90% effective in preventing Covid-19 infection, meaning that people in the trial who had been given the vaccine were 90% less likely to get Covid-19 than those who didn’t get the vaccine. The trial isn’t yet complete, however, so this could change as the study goes on and more participants catch Covid-19.
But this is talking about how many people get infected, not how many people die. Comparing this to the fatality rate for the disease is comparing two entirely different things.
It’s not yet clear whether any vaccine, in addition to reducing the chance of infection, would also reduce the chance of severe symptoms or death among those who do get infected.
Correction 19 November 2020
Correction: This article initially used figures for the number of people who died where Covid-19 was mentioned on the death certificate in any capacity, when we meant to use the figure for the number of people who died where Covid-19 was noted as the underlying cause of death.
