- The Washington Times
Wednesday, May 26, 2021

U.K. researchers have linked the AstraZeneca COVID-19 vaccine to the first incidences of strokes caused from blockages of major arteries in the brain.

Three cases of ischemic strokes, caused when a blockage prevents a vessel from supplying blood to the brain, occurred in two women and a man in their 30s or 40s. The strokes involved blockages of the carotid and middle cerebral arteries and led to the death of one patient, according to a letter published Tuesday in the Journal of Neurology, Neurosurgery and Psychiatry. Two of the patients also experienced blood clots.

All three patients had very low counts of platelets (cell segments found in blood), confirmed antibodies to platelet factor 4, and raised D-dimer levels (which is used to test for blood clots), all features of the vaccine-induced immune thrombotic thrombocytopenia (VITT) reaction, a blood clotting disorder, tied to the AstraZeneca vaccine.  

“These are first detailed reports of arterial stroke believed to be caused by VITT after the AstraZeneca COVID vaccine, although stroke has been mentioned previously in the VITT data,” senior author David Werring told Medscape.

“In patients who present with ischemic stroke, especially younger patients, and who have had the AstraZeneca vaccine within the past month, clinicians need to consider VITT as a possible cause, as there is a specific treatment needed for this syndrome,” said Mr. Werring, who is a clinical neurology professor at the University College London Queen Square Institute of Neurology. 

He added although these health conditions are serious, the benefit of the vaccine still outweighs its risks, noting that about 1 in 50,000 to 1 in 100,000 recipients of the AstraZeneca vaccine experience vaccine-induced blood clots. However, an estimated 40% of patients hospitalized with COVID-19 experience blood clots while about 1.5% have a stroke, he said. 

The first patient, a woman in her 30s who died, had a headache on the right side and around her eyes six days after getting the vaccine. She felt weakness in the left side of her face, arm and leg five days later. Imaging showed that she had a blocked right middle cerebral artery with brain infarction and clots in the right portal vein. 

The second patient was a woman in her late 30s who experienced a headache, confusion, weakness in her left arm and loss of vision on the left side 12 days after receiving the vaccine. Imaging revealed a blockage of both carotid arteries and blood clots. 

The third patient was a man in his early 40s who started having issues speaking three weeks after getting vaccinated. He had a clot in the left middle cerebral artery. 

Several countries paused the use of the AstraZeneca vaccine earlier this year amid reports of blood clots linked to the shots or limited its use to older people since the vaccine-induced blood clots appear to more frequently affect younger people. However, health experts including from the World Health Organization have ruled that the benefits of the vaccine outweigh the risks. It is recommended in the UK that people under 40 years old are offered an alternative to the AstraZeneca vaccine if possible. 

• Shen Wu Tan can be reached at stan@washingtontimes.com.

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