The federal Centers for Disease Control and Prevention is trying to understand why three of the four people who got organs from a rabies-infected donor in 2011 didn't develop the disease, the agency's top rabies expert said Wednesday.
Investigators have been puzzled because four recipients in a similar 2004 case all died of rabies within weeks. The answer could lie in the strain of rabies involved, the amount of virus in the transplanted organs, the medical history of the recipients or their genetic makeup, CDC veterinarian Richard Franka said in a telephone interview.
"It's surprising. In all previous transplant cases of solid organs, all the recipients developed rabies in a very short time," Franka said. "We are looking into it, trying to understand what mechanism was behind it."
The fourth recipient of the 2011 transplants, a Maryland man who got a kidney, died of rabies in late February. His death prompted a public health investigation that found that other organs from same Florida donor went to recipients in Florida, Georgia and Illinois. They are "very likely" out of danger, having begun post-exposure treatment before developing symptoms, Franka said.