Women and young people
“As for pseudoperniosis, it is poorly represented in our series: 0.7% compared to 2% in the American registry. Although neither the SARS-CoV-2–pseudoperniosis association nor its pathophysiology is clear, the idea is that if this manifestation is related to the host’s immune response during infection, pseudoperniosis after vaccination could also be linked to the immune response to the vaccine,” said Dr. Galván.
Many of these reactions are more intense in women. “Before starting to use these vaccines, we already knew that messenger RNA vaccines (a powerful activator of innate immunity) induce frequent reactions, that adjuvants and excipients (polyethylene glycol and polysorbate) also generate them, and that other factors influence reactogenicity, among those of us of the same age and sex, reactions being more frequent in younger people and in women,” said Dr. Galván. “This may be one of the reasons why the COVID-19 arm is so much more prevalent in the female population and that 80% of all reactions that were collected were in women.”
In relation to the fact that manifestations differed, depending on the type of inoculated serum, Dr. Galván said, “Some reactions are just as common after any of the vaccines. However, others are not, as is the case with the COVID-19 arm for the Moderna vaccine or reactivations of the herpes virus, more frequent after the Pfizer/BioNTech vaccine.
“Undoubtedly, behind these differences are particularities in the immune reaction caused by each of the vaccines and their composition, including the excipients,” she said.
Regarding the fact that these reactions were the same throughout the vaccine regimen or that they varied in intensity, depending on the dose, Dr. Galván said, “In our study, as in those carried out by other groups, there were no significant differences in terms of frequency after the first and second doses. One thing to keep in mind is that, due to the temporary design of our study and the time at which it was conducted, it was not possible to collect reactions after second doses of AstraZeneca.
“Manifestations have generally been mild and well controlled. Many of them did not recur after the second dose, and the vast majority did not prevent completion of the vaccination scheme, but we must not lose sight of the fact that 20% of these manifestations were assessed by the dermatologist as serious or very serious,” Dr. Galván added.
Regarding the next steps planned for this line of research, Dr. Galván commented, “We are awaiting the evolution of the reported cases and the reactions that may arise, although for now, our group does not have any open studies. The most important thing now is to be alert and report the data observed in the pharmacovigilance systems, in open registries, and in scientific literature to generate evidence.”
Dr. Galván has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.