On a high-speed train from Frankfurt, the man and his girlfriend experienced flu-like symptoms, a fire department official told the tabloid Bild.
The spokesperson said they had traveled from overseas to treat a man who later contracted an infectious sickness, although he did not specify the nature of the ailment.
The man did not have a temperature, and it was unknown what ailed them. He was reportedly a medical student.
They had landed in Frankfurt from Rwanda on Wednesday morning, according to the Morgenpost website in Hamburg.
The man and his girlfriend were transferred to a specialized facility when a police and fire department team arrived at the scene. Before being permitted to reopen, platform four was shuttered for a while.
The East African country is now battling an outbreak of the Marburg virus. Eight persons are reported to have died thus far in the outbreak.