Most vaccine makers have claimed promising efficacy rates for their COVID-19 vaccines, but as trials continue on larger sets of people, reports of side-effects have also emerged.
Here's a list of cases where volunteers suffered side-effects due to the vaccines.
An adverse event was reported on December 1 when a 40-year-old volunteer from Chennai, after receiving the Covishield vaccine, started to experience severe headaches and was not able to respond to questions. The participant suffered "acute neuro encephalopathy".
Though there were no side effects for the first 10 days, he subsequently had episodes like severe headache and vomiting. A notice from the volunteer's wife said, "He could neither recognise anyone nor speak and was totally disoriented and was shifted to the ICU and was on October 26 "discharged at our (family's) request"
However, Serum Institute of India, clarified and said that this incident was not related to the vaccine.
SII said, "Serum Institute of India is sympathetic with the volunteer's medical condition. However, we would like to clarify that all the requisite regulatory and ethical processes and guidelines were followed diligently and strictly. "
Exactly a fortnight after he got the first shot of Covaxin, Haryana Health Minister Anil Vij on December 5 tested positive for the infection. With Vij testing positive for the virus days after getting the dose, doubts were raised on the effectiveness of the vaccine.
Also, another incident was reported in August when a 35-year old participant with no comorbidities, who was part of Phase 1 trials at a site in western India was hospitalised with viral pneumonitis, a couple of days after being administered the vaccine. He was discharged after a week's stay in the hospital. Bharat Biotech said in a statement that the adverse event was not vaccine induced.
3) Sputnik V
Soviet nation's health minister, Mikhail Murashko, in a statement to Moscow Times, said that nearly 14% of patients who have been administered the vaccine reported suffering from side-effects. However, he termed the side-effects, routine and mild.
Recently, an independent polling institute the Levada Center found that 59 percent of Russians did not want to get the coronavirus vaccine even if it was free.
Two of the first people to receive the Pfizer-BioNTech Covid-19 vaccine in the UK had allergic reactions to the jab. They developed anaphylactoid reaction shortly after the Pfizer COVID-19 vaccine shot was given to them. Anaphylactoid reactions appear as skin rashes, breathlessness and a drop in blood pressure.
They received treatment shortly after, and are stable now. However, the British healthcare regulator has issued a warning that people with a history of significant allergic reactions should not be given the newly approved Pfizer-BioNTech COVID-19 vaccine.
During the trials, eighty-four percent of subjects reported reactions at the injection site. After getting the vaccine, 63% of trial subjects reported fatigue, 55% headaches, 32% chills, 24% joint pain, according to the data provided by Pfizer. Four patients who received the vaccine, also reported Bell's palsy, a temporary muscle paralysis in the face. Also, sixty-four subjects who received the vaccine reported swelling of lymph nodes, compared with six on the placebo.
A Moderna COVID-19 vaccine volunteer in the US, after getting two shots of the experimental drug, witnessed severe muscle aches. He also reported a low grade fever. Another candidate, who received the shot in Boston, reported stiffness in his arm and fatigue.
Both Pfizer and Moderna have admitted that taking their vaccines could result in side-effects similar to mild Covid symptoms such as muscle pain, chills and a headache. However, they said, it is impossible to contract the coronavirus from the vaccine because the mRNA vaccines that Pfizer and Moderna are making don't use the live virus.
More about the vaccines' side effects will be known in the coming months as widespread administering of the shots begin.