News of the Covid-19 vaccine waning worried many of us. Recently, the Zoe Covid Study found that the protection provided by two doses of the Pfizer/BioNTech and the Oxford/AstraZeneca coronavirus vaccines starts to decline within six months.
However, the results are not actually so alarming, because experts always expected real-world analysis to show less protection than clinical trials. The vaccines are still hugely effective in reducing serious side effects and death from the virus.
The most recent data, from the week ending 13 August 2021, shows 571 deaths registered in England and Wales which mentioned “novel coronavirus (Covid-19)”. Compare that to January 2021 – the peak of the second wave when the vaccine rollout had only just begun – and the number was 8,433 deaths in a week mentioning Covid.
The number of deaths and serious symptoms from Covid have been on the decline since the implementation of vaccines, so health professionals do universally encourage getting jabbed.
What if you’ve already had Covid?
A study in Israel (which has seen the world’s largest vaccination programme) said that having antibodies against Covid-19 from a previous infection may offer more protection against the Delta variant than being fully vaccinated against the disease.
The study found that people who had tested positive for Covid-19 were less likely to become infected, ill or need hospital treatment with the Delta strain than those who had two doses of the Pfizer vaccine, but no previous infection.
But experts say this study is limited. Because people with asymptomatic infection are typically less likely to get a test, this study may have been skewed more towards symptomatic patients.
Robert Schooley, MD, of the University of California San Diego, told MedPage Today this study doesn’t mean people should go out seeking the virus in lieu of getting the vaccine.
“Unvaccinated people who get infected are where we see the deaths occurring. Putting yourself at risk of dying to have ‘natural’ immunity is not a great tradeoff,” he said.
The World Health Organisation had a similar message, saying: “Even if you have already had Covid-19, you should be vaccinated when it is offered to you. The protection that someone gains from having Covid-19 will vary from person to person, and we also don’t know how long natural immunity might last.”
Should we be worried or shocked about vaccine efficiency?
Unfortunately, immunisation will probably not give lifelong protection against Covid-19 (just as the flu jab doesn’t give lifelong immunity against the virus), and vaccine effectiveness is expected to decline over a number of months. Scientists expected this, and are busy finalising a booster shot programme. But protection against severe disease will probably last longer than protection against infection.
Covid variants such as Delta can be transmitted easily, which is all the more reason to get vaccinated – the more people spread the virus, the more likely we are to see other variants take hold. Vaccination at least weakens this possibility.
Dr Alexander Edwards, a professor in biomedical technology at the University of Reading, as with many other experts, highly recommends getting the jab.
He said: “Vaccination does not (unsurprisingly) make people invulnerable, and does not prevent all infections. Variants have real and significant impact on public health, and a lot of people are still tragically dying in the UK from this nasty virus.
“The vaccines we have are remarkably safe and effective, and still remain far better than other vaccines that give massive benefits. We must pro-actively plan our public health strategy to account for imperfect protection, and for the possibility of falling protection over time.”