A scientist who was infected with Ebola while working for the World Health Organization in Sierra Leone has arrived in Germany for treatment in a Hamburg hospital, officials said Wednesday.

Hamburg health department spokesman Roland Ahrendt said the man would be treated in the city's UKE hospital at the U.N. agency's request.

He said "Hamburg has the capabilities to carry out this kind of treatment."

WHO spokeswoman Fadela Chaib identified the patient as a man from Senegal infected while working for the agency as a consultant.

The WHO is not giving the man's name or his condition for privacy reasons.

To date, the WHO says more than 240 health care workers have developed the disease in Guinea, Liberia, Sierra Leone and Nigeria; more than 120 have died.

The WHO had already tried to organize having another doctor sent to the Hamburg hospital for treatment in July, but the man died before he could be transported to Germany.

The WHO is not yet sure how the infectious disease expert who arrived Wednesday was exposed to the Ebola virus.

Christy Feig, director of WHO communications in West Africa, said a team of two experts was sent Tuesday to investigate whether the case occurred through straightforward exposure to Ebola patients, or something else.

She said the epidemiologist was a surveillance officer, a job that typically involves coordinating the outbreak response by liaising with local health workers, lab experts and hospitals but not direct treatment of patients.

"He wasn't in treatment centers normally," she said by telephone from Sierra Leone. It's possible he went in there and wasn't properly covered, but that's why we've taken this unusual measure — to try to figure out what happened."

She said the team is checking to make sure there isn't an infection risk in the living and working environment that had not been uncovered.

"The international surge of health workers is extremely important and if something happens, if health workers get infected and it scares off other international health workers from coming, we will be in dire straits," she said