An international study, headed by Antonio Hernández, Professor of the Department of Legal Medicine, Toxicology and Physical Anthropology of the University of Granada (UGR), has reviewed the assessment reports of the European Medicines Agency (EMA) regarding the Coronavirus vaccines produced by Pfizer, Moderna, and AstraZeneca.
Antonio Hernandez Jerez. Image Credit: University of Granada
The UGR scientists paid particular attention to the safety information from pre-clinical (animal) and clinical (phase-3 trials) dosing studies. They also considered the results of the mass vaccination campaigns in Spain and the United Kingdom to date.
Should we be concerned about the on-going vaccination drive? The principal investigator of this study, Antonio Hernández, clarifies the situation: “For our part, as the researchers, the answer is that we should not worry because the risk/benefit balance of implementing COVID-19 vaccination on a mass scale in the European Union is favorable. The benefits far outweigh the potential complications and long-term effects of actually having the disease”, he explains.
This conclusion is also valid even in light of the more serious incidents reported in the case of some vaccines, such as the blood clots associated with the AstraZeneca vaccine, “which are extraordinarily rare, while similar thrombotic complications are much more frequent among those who contract the disease,” he continues.
In general, the most commonly-reported adverse effects following the administration of the vaccines involved local reactions at the injection site (discomfort in the arm and erythema), followed by non-specific systemic effects that occurred shortly after vaccination and resolved themselves within a few days, such as myalgia, chills, fatigue, headache, and fever.
However, the study points to the continued paucity of information, on several fronts: long-term studies, interaction with other vaccines; the use of COVID-19 vaccines during pregnancy or breastfeeding; and their use in immunocompromised patients, as well as in subjects with comorbidities or autoimmune or inflammatory disorders.
There is a need for detailed follow-up and monitoring assessments for continued vaccine safety surveillance, to determine the potential risks of the aforementioned adverse incidents or diseases.”
Antonio Hernández, Professor of the Department of Legal Medicine, Toxicology and Physical Anthropology, UGR
“It is important to bear in mind that the marketing authorization granted by the EMA is only conditional, as long-term studies have yet to be carried out on animals or humans due to the need to develop and administer the vaccines urgently”, he notes.
Therefore, the EMA authorization has given the green light to use these vaccines for emergency use and rapid roll-out only, since the authorities understand the benefits to outweigh the possible long-term risks.
Under the terms of the conditional marketing authorization, long-term vaccine safety studies are mandatory, and these are currently in progress. Once finalized, the pharmaceutical companies must submit the results to the EMA for evaluation.
Hernández, A.F., et al. (2021) Safety of COVID-19 vaccines administered in the EU: Should we be concerned?. Toxicology Reports. doi.org/10.1016/j.toxrep.2021.04.003.