Where risk is involved, science deals in probabilities not certainties. Communication around vaccines must accept that reality
Every day, people take medicines with known side-effects. The risk is accepted when weighed against the benefit. But Covid vaccines are unfamiliar. There is no record of use over time to build public confidence. Still, they have been tested and proven to offer protection against the virus. By all usual medical standards, they are safe. That remains true for the AstraZeneca vaccine, despite an evolving picture that side-effects might include a rare blood clotting disorder.
The UK’s Medicines and Healthcare Products Regulatory Authority is still investigating the link, but has recommended, as a precaution, that other vaccines be preferred for recipients under 30. That is a notable shift in policy when ministers have dismissed any talk of risks associated with the jab. The European Medicines Agency on Wednesday recommended that blood-clotting be added to the list of “very rare” side-effects of the AstraZeneca vaccine; not sufficient to require a change in patterns of use.
