Doctors at the center said he may have infected several people who came in contact with him.

The 2003 study estimated that the blood program had infected 199,000 people.

Every year, it infects 50 to 100 million people around the world.

They say there is no evidence that it can infect people.

"That still gives them a lot of time to infect other people."

An outbreak there in 1997 infected only 18 people but killed 6 of them.

How one person could infect so many people was a mystery.

"I tell myself this guy is infecting other people," he said.

Two of the women did not pass on the germ, but one infected more than 20 people, both patients and hospital workers.

It is unclear how many people worldwide are infected at present.