The COVID-19 vaccine participant whose unexpected illness put the AstraZeneca trials on pause came down with an inflammatory syndrome known as transverse myelitis, according to a report.
The individual had been involved in the U.K. trials when they came down with the condition, which affects the spinal cord and is often sparked by viral infections, a source told The New York Times.
The illness results in inflammation of both sides of the spinal cord, interfering with how messages are sent throughout the body and potentially causing paralysis, according to the Mayo Clinic.
It’s also associated with pain, muscle weakness, sensory problems, or bladder and bowel dysfunction.
The drug giant vowed to investigate whether the vaccine, which was developed with the University of Oxford in Britain, was responsible for the syndrome.
“This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials,” AstraZeneca said in a statement.
“In large trials, illnesses will happen by chance but must be independently reviewed to check this carefully.”