SOUTH SAN FRANCISCO (KPIX) – The global trials of leading COVID-19 vaccine candidate AstraZeneca have been put on hold after a suspected adverse event.

According to Stat News, a media company that reports on health and medicine, it was a woman in the United Kingdom who triggered the global shutdown of the AstraZeneca vaccine trial.

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“This particular candidate from the AstraZeneca company had a serious adverse event,” said NIAID Director Dr. Anthony Fauci.

Sometime after she was injected with the actual vaccine, the woman experienced symptoms consistent with a neurological disorder called “transverse myelitis,” a rare but serious inflammation of the spinal cord.

Dr. Francis Collins is the director of the National Institutes of Health. He told a Senate panel what happens next.

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“With an abundance of caution you put a clinical hold, you investigate it carefully to see if anybody else received the vaccine or any other vaccines may have had a similar finding of a spinal cord problem,” said Dr. Collins.

Bay area epidemiologists, Dr. Art Reingold of UC Berkeley and Dr. George Rutherford of UCSF both agree that pausing an advanced vaccine trial is not unexpected.

“I would say what this shows is that these trials are being done properly with the proper safeguards,” said Dr. Reingold.

“I think what people need to know is that we’re trying to develop these vaccines as safely as possible,” added Dr. Rutherford.

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This week, nine drug manufacturers took a rare step and signed a pledge saying that they would not seek approval from the Food and Drug Administration before advanced trials show their vaccine is safe.

Elizabeth Cook