An Instagram post shares a picture of a headline which says: “Study of 145 countries finds sharp rise in virus transmission and death AFTER introduction of Covid vaccines”. It is accompanied by a caption which outlines the details of the study and says that people weighing up the decision to have a Covid-19 vaccine may want to “keep a recent study in mind that indicates an association between the vaccines and a higher rate of COVID-19 infections and deaths”.
However, the study that this claim comes from is deeply flawed. There is a lot of evidence which shows the contrary.
The headline comes from an article on a website called Newstarget, which is no longer online. It is based on a personal research project by a political science PhD student which has not been peer reviewed or published in an academic journal.
The study analyses data from 145 countries and compares data on Covid-19 cases and deaths, with a prediction of what would have happened without the intervention of vaccination. This prediction or ‘projected trend’ was created by using four countries with low vaccination rates (Burkina Faso, Chad, Democratic Republic of Congo and South Sudan) as a ‘control’, using these countries as examples to inform predictions of how the pandemic would have evolved in other countries if there had been limited interventions from the vaccines.
The study concludes that the analysis indicates a “marked increase in both COVID-19 related cases and death due directly to a vaccine deployment” and that its results should “encourage policy makers to begin looking for other avenues out of the pandemic aside from mass vaccination campaigns”.
Elizabeth Williamson, an associate professor in the Department of Medical Statistics at the London School of Hygiene and Tropical Medicine (LSHTM), told Reuters that she had “very low confidence in the results of this analysis,” and said that the paper took “a very naive approach to an incredibly complex question without discussing the plausibility of the very strong assumptions being made”.
She added that the decision to use four countries in Africa to represent what would have happened in other countries around the world if they had not introduced the vaccine “is very unlikely to give a sensible answer.”
Professor Linda Sharples, head of LSHTM’s Department of Medical Statistics, told Reuters the paper had drawn together “aggregate data from a wide range of very different countries” which “vary widely” in age distribution of their citizens and their geographic, economic and other population statistics. These countries also have different Covid-19 strategies.
She said: “Combining data in this case is fraught with difficulty and likely to be misleading”.
As described by Health Feedback, there are also other flaws to the analysis as it does not account for variables such as changing variants of the virus, the different public health measures that were introduced during different periods, the impact of differing healthcare capacity and capability, and whether deaths occurred in vaccinated or unvaccinated people within the populations.
There is now lots of available data to help us to establish the efficacy and impact of the Covid-19 vaccines. For example there is published, peer reviewed efficacy data from the initial randomized control trials into the Covid-19 vaccines currently in use in the UK (although this data doesn’t include more than a few months follow up after vaccination, and pre-dated the subsequent variants of Covid-19).
Data from England published by the UK Health Security Agency (UKHSA), has shown that with a booster dose, the vaccines offer 45-75% protection against symptomatic infection between two to 10 weeks after the booster, and approximately 85-90% efficacy against hospitalisation against the Omicron variant (although the duration of protection is still being assessed).
The latest data from the UKHSA also shows that while the rate of testing positive for Covid-19 between vaccinated and unvaccinated people varies by age group and is sometimes higher in vaccinated groups, the rate of hospitalisation and death is “substantially greater in unvaccinated individuals compared to vaccinated individuals”.
The UKHSA also explains that the varying rate of a positive Covid-19 test in different age groups and vaccination statuses is likely to be due to a variety of reasons, including differences in the population of vaccinated and unvaccinated people as well as differences in testing patterns.
We have written many times before about the effectiveness of the Covid-19 vaccines, and the fact that the Covid-19 vaccines do not cause Covid-19 infections.
Image courtesy of Daniel Schludi, via unsplash.