A researcher who was exposed to the deadly Ebola virus and received an experimental vaccine has passed the disease's 21-day incubation period without showing any sign of falling ill, her German employer said Thursday.
Dr. Stephan Guenther, head of the laboratory where the 45-year-old woman worked, said that she is being prepared for release from a Hamburg hospital.
"We believe she's overcome everything," Guenther said. "It's been three weeks. That's a very conservative estimate for Ebola."
The researcher, whose identity has not been released, was conducting experiments on mice when a needle accidentally slipped and nicked her finger through three layers of protective gloves.
Within 48 hours, she was administered an experimental vaccine for Ebola, never tried before on humans.
It remains unclear whether the vaccine prevented the woman from falling ill or whether she was never infected with the deadly virus in the laboratory of the Bernhard Nocht Institute for Tropical Medicine in Hamburg.
Guenther said researchers will analyze the woman's blood for antibodies in an attempt to determine whether they came solely from the vaccine or whether she was generating others on her own, signaling that she had been infected.
"It's possible we'll never know with 100 percent certainty," he said.
Ebola hemorrhagic fever, seen mostly in Africa, is one of the world's most feared diseases.
It begins with flu-like symptoms, followed by bloody diarrhea and vomiting. Days later, some victims begin bleeding through the nose, mouth and eyes. Depending on the strain of virus, it can kill up to 90 percent of victims.
So far, there is no cure. The virus is spread through direct contact with the blood or secretions of an infected person.