AstraZeneca Covid vaccine: weighing up the risks and rewards

Despite scientific advice to continue getting the jab, answers about fatal blood clots are urgently needed

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Vaccines have side-effects, as do all medicines. Most often, jabs cause sore arms, a headache or a bit of nausea - none of which would be very significant when weighed against the toll of a serious virus such as Covid-19.

But sometimes the risk-benefit calculation may look less simple, as in the case of Oxford/AstraZeneca's Covid jab and cerebral venous sinus thrombosis (CVST), the blood clots in the brain that have led to fatalities in the UK and Europe.