Medical tests came back negative for two people in Hamburg feared to have the Marburg virus, the German authorities said on Thursday, a day after they were taken to hospital on fears they were infected with the life-threatening haemorrhagic fever. One of them is a medical student who came into contact with an infected person while treating patients abroad. Doctors feared they were infected with the Marburg virus, which can cause high fever, haemorrhaging and other symptoms close to Ebola, which is the same sort of virus. The student is to continue to be monitored until the end of the incubatio…