In a statement sent to Efe, a university spokesperson noted that although there is no concern about safety in the pediatric clinical trial, Oxford has decided to wait to have additional information from the MHRA in its investigation of rare cases of thrombosis before administering more vaccines.

"Parents and children should continue to go to all their planned visits and can contact the testing sites if they have any questions," the spokesperson said.

This announcement, which does not mean that the trials are finished but that they are put on "pause" until the regulator's conclusions are reached, comes at a time when distrust is growing in the UK towards the Oxford / AstraZeneca vaccine, which was used for most of the 31.6 million Britons who already have the first dose.

The British Government has urged all citizens to continue to go to be vaccinated when they are summoned, either to receive the injection of AstraZeneca or that of Pfizer, the only two vaccines approved so far in the country.

Seven people have died in the UK from rare blood clots after receiving AstraZeneca's covid-19 vaccine.

The MHRA noted last week that 30 cases of these rare blood clots have been identified among the 18.1 million people vaccinated with that preparation as of the end of March.

Of the 30 incidents, 22 correspond to venous cerebral thrombi (CVST) and eight to other problems related to blood clotting with low platelets.