Largest Study Ever Shows COVID Vax Increases Neurological, Cardiac Conditions

NEW YORK (VINnews) — The largest study of COVID-19 vaccine receivers which has so far been conducted concludes that the vaccines prevent severe illness, death and long COVID symptoms, but are also linked to small increases in neurological, blood, and heart-related conditions, according to a Fortune magazine report.

The new research, by the Global Vaccine Data Network, was published in the journal Vaccine last week, with the data made available via interactive dashboards to show methodology and specific findings.

The  study, encompassing 99 million people from eight countries who had received the vaccine, focused on 13 medical conditions that the group considered “adverse events of special interest”,  aiming to identify higher-than-expected cases after a Covid shot.

Research results included a higher risk of heart-related inflammation from mRNA shots made by Pfizer Inc., BioNTech SE, and Moderna Inc., and an increased risk of a type of blood clot in the brain after immunization with viral-vector vaccines such as the one developed by the University of Oxford and made by AstraZeneca Plc.

The viral-vector jabs were also tied to an increased risk of Guillain-Barre syndrome, a neurological disorder in which the immune system mistakenly attacks the peripheral nervous system.

More than 13.5 billion doses of Covid vaccines have been administered globally over the past three years, saving over 1 million lives in Europe alone.  Yet a small proportion of people immunized suffered adverse effects from the shots, stoking debate about their benefits versus harms.

Myocarditis, or inflammation of the heart muscle, was consistently identified following a first, second and third dose of mRNA vaccines, the study found. The highest increase in the observed-to-expected ratio was seen after a second vaccination with the Moderna shot. A first and fourth dose of the same vaccine was also tied to an increase in pericarditis, or inflammation of the thin sac covering the heart.

Researchers found a statistically significant increase in cases of Guillain-Barre syndrome within 42 days of an initial Oxford-developed ChAdOx1 or “Vaxzevria” shot that wasn’t observed with mRNA vaccines. Based on the background incidence of the condition, 66 cases were expected — but 190 events were observed.

ChAdOx1 was linked to a threefold increase in cerebral venous sinus thrombosis, a type of blood clot in the brain, identified in 69 events, compared with an expected 21. The small risk led to the vaccine’s withdrawal or restriction in Denmark and multiple other countries. Myocarditis was also linked to a third dose of ChAdOx1 in some, but not all, populations studied.

Possible safety signals for transverse myelitis — spinal cord inflammation — after viral-vector vaccines were identified in the study. So was acute disseminated encephalomyelitis — inflammation and swelling in the brain and spinal cord — after both viral-vector and mRNA vaccines.

Seven cases of acute disseminated encephalomyelitis after vaccination with the Pfizer-BioNTech vaccine were observed, versus an expectation of two.

The adverse events of special interest were selected based on pre-established associations with immunization, what was already known about immune-related conditions and pre-clinical research. The study didn’t monitor for postural orthostatic tachycardia syndrome, or POTS, that some research has linked with Covid vaccines.