LONDON (REUTERS) - There is a much higher risk of brain blood clots from Covid-19 infection than there is from vaccines against the disease, British researchers said on Thursday (April 15), after the roll-out of inoculations was disrupted by reports of rare clots. AstraZeneca and Johnson & Johnson have both seen very rare reports of cerebral venous sinus thrombosis (CVST) linked to their vaccines. On Wednesday, the United States paused vaccinations using J&J's shot while a link with clots was investigated, with Denmark ditching AstraZeneca's shot over the issue. British and European regulators have stressed that the benefits of vaccination outweigh the risks.