You didn't include the author of the paper from which this abstract was taken but it's by J. B. Classen.
Classen is a well known anti-vaccinationist who's publications on the supposed adverse effects of other vaccines have been found to have no scientific basis.
One key requirement for science based research is that findings be able to be reproduced in follow up studies. Previous claims by Classen that vaccination was linked to development of diabetes were not supported by subsequent research.
As just one example of poor scientific method, in the paper you've used, Classen also says:"Many have raised the warning that the current epidemic of COVID-19 is actually the result of an bioweapons attack released in part by individuals in the United States government [10,11]."
The papers (10 & 11) Classen has cited to support this major statement are both authored by J B Classen alone. Classen was apparently unable to find any source to support his statement other than his own previous writings.
In short, the source you've used is lacking scientific credibility.
