Covid-19 vaccine side effects weren't broken down by gender: Report
Research carried out into the side effects caused by five Covid-19 vaccines did not state if side effects differed by men and women, despite four of the vaccine producers examining efficacy based on gender. So far, the Dutch side effects research center Lareb has said that nearly 87 percent of all side effects reported have come from women.
Investigative journalism platform Investico published the finding on Wednesday in cooperation with Trouw, EenVandaag and De Groene Amsterdammer. Reporters analyzed the clinical reports of Pfizer/BioNTech, Moderna, AstraZeneca, Sputnik V and Janssen, the latter being the Leiden-based vaccine developer owned by Johnson & Johnson. None of the companies broke their side effect data down according to sex. AstraZeneca was the only one of the four to not report vaccine efficacy based on gender, according to Investico.
For the European Medical Agency, a sex-specific analysis of adverse reactions is not a mandatory requirement for vaccine approval.
Worldwide, women have reported far more side effects than men, Investico reported. In the Netherlands alone, Lareb, received reports from 26 thousand people about the 152 thousand adverse reactions they experienced after a Covid-19 vaccination. An estimated 86.6 percent of the complaints were submitted by women. Some incidents include heavy reactions such as thrombosis after administration of the AstraZeneca vaccine or a heavy allergic response to the Pfizer and Moderna vaccines.
“We are not sure why women report complaints more often”, said Lareb director Agnes Kant. She said one explanation could be that many young women work in health care and, therefore, were vaccinated earlier. It has also been speculated that healthcare workers are more likely to report the side effects they experience.
“Do they experience more symptoms? Do they actually have complaints? Do they ring the alarm earlier?” Kant wondered.
By not dividing the data by gender, UMC Maastricht researcher Chahinda Ghossein-Doha believes an important opportunity was missed. Overall, the coronavirus seemed to cause affect men and women differently. Men are more likely to die from Covid-19 while women are more prone to suffer from long-term effects of the disease. “Scientifically, you cannot avoid researching the connection between sex and Covid-19, or the treatment methods and medication," Ghossein-Doha said to Investico.
Pharmacists believe that other factors, such as age, play a more decisive role. “Age has a much larger impact because the immune system ages along with the person, making the vaccine less effective amongst the elderly," said Marc Kaptein, the Medical Director of Pfizer Nederland.