All about two rare Covid-19 vaccine side effects detected in a study | Health

Two new rare side effects of Covid-19 vaccine have been uncovered by a recent study published in international journal Vaccine. Researchers working as part of the Global Vaccine Data Network identified acute disseminated encephalomyelitis – an inflammation and swelling in the brain and spinal cord and the same has been linked to the AstraZeneca vaccine. The study also confirmed that Pfizer and Moderna vaccines have rare side-effects of myocarditis (inflammation of the heart muscle) and pericarditis (swelling of the thin sac covering the heart) apart from Guillain-Barré syndrome (where the immune system attacks the nerves) and cerebral venous sinus thrombosis (a type of blood clot in the brain) as rare side effects linked to the AstraZeneca vaccine. (Also read: Heart attack cases not rising due to Covid vaccine, but stress and other traditional factors, says cardiologist)

The study included more than 99 million people from Australia, Argentina, Canada, Denmark, Finland, France, New Zealand and Scotland, with researchers confirming that the benefits of Covid-19 vaccines still ‘vastly outweigh the risks’.

Neurological disorder: Acute disseminated encephalomyelitis

The first rare side effect that the study found out is a neurological disorder called Acute disseminated encephalomyelitis, which is linked with AstraZeneca vaccine.

According to National Institute of Neurological Disorders and Stroke, Acute disseminated encephalomyelitis (ADEM) is a neurological disorder characterised by brief but widespread attacks of inflammation (swelling) in the brain and spinal cord that damages myelin. Myelin is the whitish protective coating over nerves that helps with electrical nerve signalling.

ADEM symptoms include loss of vision in one or both eyes, extreme weakness, difficulty in coordinating intended (voluntary) movement such as walking, rapid onset of fever, and some degree of impairment of consciousness.

The Australian study found that there was an extremely small risk of acute disseminated encephalomyelitis of 0.78 cases for every million doses, and 1.82 cases per million doses for transverse myelitis.

Inflammation of spinal cord: Transverse myelitis

Transverse myelitis is a neurological condition and is basically an inflammation of spinal cord and is seen in people with autoimmune conditions. It may at times be a warning sign of multiple sclerosis.

Common symptoms of Transverse myelitis are back or neck pain, weakness or sensation changes in the arms or legs, or loss of bladder or bowel control. High doses of steroids are used to suppress the activity of the immune system and for quick recovery.

As per this study the risk of developing transverse myelitis was 1.82 cases per million doses.

Covid vaccines played an important role in controlling the spread of the virus, but the reports of its side effects including its impact on heart have been widely debated. Typical side effects of the vaccine include pain at the injection site, fever, fatigue, headache, muscle pain, chills and diarrhoea. In rare cases, inflammatory diseases of the heart post vaccination with Pfizer or Novavax such as myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the outer lining of the heart) have been reported.