Eleven people who received the AstraZeneca-Oxford Covid-19 vaccine have developed a rare neurological disorder called Guillain-Barre syndrome, clinicians in India and England have reported in two separate studies.
While seven cases were reported from a medical centre in Kerala, where about 1.2 million people were administered the AstraZeneca Covid-19 vaccine, known as Covishield in India, four were reported from Nottingham, UK, in an area in which approximately 700,000 (7 lakh) people received the jab.
In Guillain-Barre syndrome (GBS), the body’s immune system mistakenly attacks part of its peripheral nervous system –the network of nerves located outside of the brain and spinal cord.
The two studies, published in the journal Annals of Neurology on June 10, describe an unusual variant of GBR characterised by prominent facial weakness.
The frequency of GBS from the areas where the cases were reported was estimated to be up to 10 times greater than expected, the authors of the two studies said.
As of April 22, 2021, around 1.5 million individuals in three districts of Kerala, had been vaccinated with Covid-19 vaccines, the researchers noted, adding that over 80 per cent of these individuals (1.2 million) received the AstraZeneca preventive.
In this population, during the period from mid-March to mid-April 2021, the researchers from Aster Medcity, Kochi, and Indo-American Brain and Spine Center, Vaikom, Kerala, observed seven cases of GBS that occurred within two weeks of the first dose of vaccination.
All seven patients developed severe GBS, the researchers said.
The frequency of GBS was 1.4 to 10-fold higher than that expected in this period for a population of this magnitude, they said.
The frequency of facial weakness on both sides of the face, which typically occurs in less than 20 per cent of GBS cases, suggests a pattern associated with the vaccination, according to the research authors.
“While SARS-CoV-2 vaccines are very safe, we report four cases of the bifacial weakness with paraesthesias variant of GBS occurring within three weeks of vaccination with the Oxford-AstraZeneca SARS-CoV-2 vaccine,” said the authors of the UK study from Nottingham University Hospitals NHS Trust.
“We suggest vigilance for cases of bifacial weakness with paraesthesias variant GBS following vaccination for SARS-CoV-2 and that post-vaccination surveillance programmes ensure robust data capture of this outcome, to assess for causality,” they added.
Although the benefits of vaccination substantially outweigh the risk of this relatively rare outcome (5.8 per million), the researchers noted that clinicians should be alert to this possible adverse event.
