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First of all, two of those links go to blogs, both of which use the medrxiv.org article as their source. Of course, the blogs exaggerate with the intent of scaring people even more about vaccines. I will say no more about the blogs.

Did you actually read the original article posted on the medrxiv.org website?

The authors of this article point out several times that this finding must be verified using more stringent methods than what they used.

At this point, I will post selections from the article and give layperson interpretations where I think they are needed.

However, in a post-hoc sensitivity analysis, the seizures/convulsions signal was sensitive to background rates selection and was not observed when 2022 background rates were selected instead of 2020 rates.

This statement raises the strong likelihood that the signal was spurious, meaning that it was an artifact of the analysis and not a real signal.

The new signal detected for seizures/convulsions among younger children should be further investigated in a robust epidemiological study with better confounding adjustment.

In other words, another study needs to be done in a more careful manner.

However, results of such study design do not establish a causal relationship between the vaccines and health outcomes and need to be interpreted with caution because of the limited adjustment for confounding and other forms of bias.

This is the author's way of pointing out that correlation does not necessarily mean causation. This is meant to highlight the fact that this observational study cannot establish a causative link between vaccination and the observed seizures.

The seizures/convulsions signal in children aged 2-4/5 years has not been previously reported for this age group in active surveillance studies of mRNA COVID-19 vaccines. However, there are reports from the Vaccine Adverse Events Reporting System (VAERS) database which is a passive reporting system and has limitations. In an analysis of VAERS data, only 8 seizures were identified following approximately one million mRNA vaccinations through August 2022 in the age group 6 months to 5 years. Six of the 8 seizures were afebrile on medical evaluation.

This rather long passage points out that this is the only study out of many that ever found seizures following vaccination. This means that the authors are pointing out that this is likely to be a spurious result. Whenever statistical methods are used to analyze data, there is ALWAYS a risk of a spurious (not real) result.

Seizure risk after COVID-19 vaccination was lower in children who were seizure free for more than six months before vaccination. However, the incidence of general adverse events after vaccination was low with no severe adverse events recorded. Generally, there is limited evidence linking the mRNA COVID-19 vaccines to a seizure onset among vaccinated children aged 2-4/5 years. The new seizures/convulsions signal observed in our study should be interpreted with caution and further investigated in a more robust epidemiological study.

This is another reiteration of the author's view that the observation of seizures after vaccination is likely to be spurious.

Since febrile seizures can be common in young children for a variety of reasons; the analysis may have identified febrile seizures unrelated to the vaccination later in the risk window.

Again, likely to be spurious.

However, seizures/convulsions rates in this age group in 2022 were twice as high as 2020 rates. There could be a couple of potential reasons for elevated outcome rates in 2022 compared to 2020. First, there was an increased incidence of respiratory infections (influenza and respiratory syncytial virus) which are shown to be associated with febrile seizure in younger children, during the study period (mid-2022 to mid-2023) compared to 2020. Second, in 2020, there were likely fewer emergency department visits for seizure-related events compared to 2022 because of COVID-19 pandemic healthcare resource limitations.

The authors are explaining that lack of medical resources during the beginning of the pandemic and the increase of respiratory infections in 2022 are probably responsible for the seizures they saw in the study.

FDA concludes that the known and potential benefits of COVID-19 vaccination outweigh the known and potential risks of COVID-19 infection.

Self-explanatory.

Editorial note: This study was funded by the FDA and, so far, is only published on a preprint site and is not peer-reviewed. It is possible that this study will never be published in a scientific/medical journal.

I highly recommend reading the original study rather than the antivax website misinterpretation of it. And if you can't understand the scientific language, find someone who can interpret it for you. I think that there are plenty of scientists such as myself who take the time and effort to explain technical jargon in a way that people can understand.