Earlier this week it was announced that AstraZeneca, a pharmaceutical company conducting one of the leading COVID-19 vaccine studies, has ceased operations due to possible medical complications in a participant. Health news website STAT reported this morning that the participant who got sick was a woman in the UK. Although not officially confirmed, she appears to have a condition called transverse myelitis. STAT reports that she will likely be released from the hospital soon.
Myelin is a substance that covers nerve fibers, the body's version of fiber optic cables that carry signals around the body. Transverse myelitis occurs when the spinal cord becomes inflamed. According to the National Institute of Health, transverse myelitis has many causes, including bacterial and viral infections and immune disorders.
In some cases, transverse myelitis can be a rare reaction to vaccination. But there are many other explanations.
This wasn't the first break in the AstraZeneca vaccine trials. They were stopped once before in July when another participant fell sick. This person was eventually diagnosed with multiple sclerosis, a degenerative disease not associated with the vaccine.
Further investigation is needed in this case of transverse myelitis before studies can begin again.