Covid-19 vaccines linked to risk of heart, brain and blood diseases – World

Pfizer, Moderna and AstraZeneca, vaccines used to combat Covid-19, are associated with rare occurrences of heart, brain and blood diseases. The conclusions are from a recent study released by the Global Vaccine Data Network, a research company belonging to the World Health Organization.

Researchers assessed, in a universe of more than 90 million people from eight countries, the risk of adverse events from 13 medical conditions of special interest after vaccination against COVID-19. To date, this is the largest study on vaccines against Covid-19.

In the research, some cases of myocarditis – inflammation of the heart – were identified in people who had taken the first, second and third doses of the Pfizer and Moderna vaccine. The highest rate was recorded after the second dose of Moderna.

Periocarditis, another heart disease, had a 6.9 times higher risk in people who took a third dose of the AstraZeneca vaccine.

The risk of developing Guillain-Barré syndrome, a rare autoimmune disease, was 2.5 times higher in people who took the AstraZeneca vaccine, compared with the rate expected by researchers.

The population that took the same vaccine was also found to have a 3.2 times higher risk of contracting blood clots.

Regarding neurological diseases, the researchers point out that the risk of acute disseminated encephalomyelitis was 3.8 times higher after administration of the Moderna vaccine and 2.2 times higher after the AstraZeneca vaccine.

Although the data warns of the possibility of contracting these diseases, the researchers explain that “the benefits of vaccination substantially outweigh the risks”.