A study published by the United States' Center for Disease Control and Prevention (CDC) has revealed that women made up a majority of those reporting adverse effects to the COVID-19 vaccine.
Nearly 7,000 people had reported to the CDC that they were experiencing side effects after receiving the vaccine, including symptoms of headaches, fatigue, and dizziness. Out of which, 80% of women reported side effects.
The vaccines subject to the study were the Pfizer-BioNTech and Moderna COVID-19 vaccines which involve 2 doses each.
The study was conducted using the Vaccine Adverse Events Reporting System (VAERS) and was focused on long-term residents of care facilities and health workers who were the first to receive vaccines. The study highlights that 61% of adverse reactions to the vaccines occurred in elderly women over the age of 83. Among women who were not in care facilities for the elderly, the reporting rate rose to 72.1% with the average age of women reporting at 42 years.
The survey conducted by researchers at the CDC analyzed data on more than 13 million recipients of the coronavirus vaccine as of January 13.
Over the course of a month, a total of 13,794,904 COVID-19 vaccines were administered to Americans — of which 8,436,863 (61.2%) were administered to women.
The pattern of vaccine reactions fit in with earlier research conducted in 2013 and 2009 which demonstrates that women were more likely to incur a bad reaction from vaccines than men.
The side effects listed by the CDC include pain, swelling, fever, chills, headache and tiredness. This list has been updated with three new symptoms including rashes, muscle pain and nausea. However the robust immune response generated by the vaccine has demonstrated a drop in the need for hospitalisation in COVID-19 sufferers.
Speaking to the New York Times, Sabra Klein, a microbiologist and immunologist at the Johns Hopkins Bloomberg School of Public Health, told the paper that she was "not at all surprised," given that "this sex difference is completely consistent with past reports of other vaccines." However she also clarified that the effects were short-lived and a sign that the body was mounting a good immune response that would protect from the worst of the COVID-19 virus.
Scientists speculate that the difference in reactions may be due to hormonal fluctuations in women as well as the fact that women were more likely to report adverse effects or seek healthcare diagnoses than men.