The next wave of Covid will be different. When cases skyrocketed in the spring and winter of last year, the lockdowns quickly brought them back under control. This time it will be the vaccines that do the hard work.
But Covid hits are not a perfect shield. They reduce the spread of the virus, help prevent disease, and reduce the risk of death. They don’t put an end to all this.
In the coming months, many thousands of people will be hospitalized with Covid. What may seem more worrying is that more and more people will have received two doses of vaccination.
This does not mean that vaccines are not doing their job. Real-world data from Public Health England shows that two injections of the Oxford / AstraZeneca or Pfizer / BioNTech vaccine are 92% and 96% effective, respectively, compared to hospital admission.
On Thursday, Vaccine Minister Nadhim Zahawi said the vaccine program had prevented some 52,000 hospitalizations.
So why will most of those in the hospital with Covid be hit twice as hard? There are several factors at play. First of all, it is important who has been vaccinated and who has not. Across the UK, around 30% of adults are not fully vaccinated. While some are vulnerable people who have not been pricked for some reason, most are young and healthy enough not to be considered at particular risk – these are people who would very rarely get sick enough from Covid-19 to need hospital care.
Seen another way, the 70% of the population that has doubled includes the most vulnerable in society. Because vaccines are not perfect, even a small percentage of what scientists call “breakthrough infections” can lead to large numbers of hospitalizations, predominantly in this group of older people.
The total number of hospitalizations for Covid will be dramatically lower than in a world without vaccines, but newcomers increasingly like having received both injections.
“Imagine if all adults had already been fully vaccinated,” says Kevin McConway, emeritus professor of applied statistics at The Open University. “We know that there will still be some hospitalizations, because the vaccines are not perfect, but for adults all those hospitalizations would be in vaccinated people. That doesn’t mean vaccines don’t help, just that they don’t provide perfect protection, and no one said they did. “
England Public Health Data since the beginning of July it confirms it. Of the 257 deaths from confirmed Delta variant infections between February and the end of June, only two of the 26 deaths in those under 50 years of age were doubly injected. That compares with 116, or more than half, of the 231 deaths in those over 50.
“If you are fully vaccinated, the risk of being hospitalized is reduced by about 90%,” said Professor David Spiegelhalter, president of the Winton Center for Risk Communication and Evidence, at the University of Cambridge. “But it does not go away, and since a large proportion of people at higher risk are now vaccinated, it is inevitable that most people with Covid will begin to form in the hospital, especially since most of the unvaccinated people are young and therefore, they are at low risk. In fact, being young reduces the risk even more than being vaccinated.
Another important factor at play is age. McConway says the risk of an infected person being hospitalized is at least 10 times higher, and up to 25 times higher, for a 75-year-old than for a 25-year-old. If the latter risk is correct, then a vaccine that prevents the 96% of hospitalizations would reduce admissions among 75-year-olds to that seen in the youngest 50 years.
When it comes to deaths from Covid, a fully vaccinated 80-year-old has a risk similar to that of an unvaccinated 50-year-old.
Future twists and turns of the pandemic can still change the math. Having a large wave of infections with about half the UK population vaccinated provides the right conditions for a variant that can better evade the protection of vaccines.
Another concern is how soon the vaccines wear off. Several studies have shown that antibody levels decrease over time, but it is unclear what the decreases mean for immunity and protection against infection, hospitalization, and death. The answer could clarify in the months to come. As hospitals prepare for another wave of patients, health officials will watch closely to see if more beds are needed for the first ones.
George is Digismak’s reported cum editor with 13 years of experience in Journalism