Democratic Republic of Congo Halting the vaccine rollout is "baffling," said Dr. Michael Head, a senior research fellow in global health at the University of Southampton. Speaking to the Science Media Centre on Monday, Head said that data suggested that the number of blood clots in the vaccinated population was the same as, or even lower than, in the general population. "Halting a vaccine roll out during a pandemic has consequences. This results in delays in protecting people, and the potential for increased vaccine hesitancy," he said. Also speaking to the SMC, Dr. Stephen Griffin of the School of Medicine at the University of Leeds called the suspensions "probably not proportionate."