What are the possible adverse reactions to vaccine shots mentioned in guidelines?

New Delhi, Jan 15: Prime Minister Narendra Modi will virtually kick-off India's massive coronavirus vaccination drive on Saturday. The Covid-19 vaccine rollout is expected to cover 3 lakh frontline healthcare workers across 3,006 sites in India.

The cost of the vaccination of healthcare and frontline workers will be borne by the Indian government. The vaccines have been allotted to respective states and union territories based on the health workers' data.

While the rollout is set to begin in 24 hours, it will be months before the vaccine will be available at a pharmacy store near you.

Millions of people nationwide are hoping for the vaccination against the fatal virus. Also, vaccines have been found safe and approved by health authorities in many countries.

However people are also ambivalent because of the fear of possible side effects from vaccination. They have doubts as to whether the vaccines are actually safe, given the rapid pace of development, and whether possible side effects have been adequately studied.

COVISHIELD

Mild adverse reactions

For Covishield, the fact sheet says a few mild adverse events can happen following immunisation -injection site tenderness; injection site pain; headache; fatigue; myalgia (deep muscle pain); malaise (a feeling of overall discomfort); pyrexia (an abnormal elevation of body temperature); chills; arthralgia (pain in the joint); and nausea.
In such cases, the fact sheets say the common painkiller paracetamol may be used "to provide symptomatic relief from post-vaccination adverse reaction".

Rare adverse reactions

The nerves in the body are covered with a protective layer called myelin - like a network of electric wires that helps transmit messages from the brain smoothly through the body. Conditions that damage myelin are called demyelinating disorders. The fact sheet says "very rare events of demyelinating disorders" have been reported following vaccination with Covishield, "without the causal relationship establishment".

It adds that Covishield should be given with "caution" to individuals with thrombocytopenia, a medical condition characterised by abnormally low levels of platelets.

COVAXIN

Mild adverse reactions

Among mild adverse events following immunisation, the fact sheet includes: injection site pain; headache; fatigue; fever; body ache; abdominal pain; nausea and vomiting; dizziness-giddiness; tremor; sweating; cold; cough; and injection site swelling.

Rare/serious adverse reactions

None are listed. Bharat Biotech, the manufacturer, has said no serious adverse event has been reported in either phase 1 or phase 2 trials - or in the ongoing large phase 3 trials with 25,800 participants, it has said.

Bharat Biotech has also said that chloroquine and corticosteroids, both used as repurposed drugs in Covid-19 clinical management, "may impair antibody response" likely to be triggered by the vaccine.