They wore protective gear including face shields, hazardous materials suits and protective footwear as they inserted catheters, drew blood and dealt with his body fluids. Still, the two somehow contracted Ebola from the dying man.
As health officials try to figure out how that happened, the nurses' cases have brought new scrutiny to national Ebola protocols that had never before been put to the test at a general hospital. Authorities are examining whether those guidelines need to be rewritten.
The federal Centers for Disease Control and Prevention protocols for Ebola recommend that nurses use personal protective equipment such as gloves, goggles, face shields and fluid-resistant gowns — as Vinson and Pham did. They also recommend diligent cleaning and disinfection of any items containing contaminated materials.
CDC director Dr. Tom Frieden has cited a "breach in protocol" that allowed Pham to be infected while she cared for Duncan in the intensive care unit, but has not specified the nature of that breach. He did however note that some of the nurses at Texas Health Presbyterian Hospital inadvertently violated the CDC protocols by wearing too much protective gear.
Online, the CDC sought Wednesday to clarify the Ebola protocols in a health care setting, adding specifics on a website about double-gloving and restricting the number of caregivers involved. These are recommendations, not requirements. More than 75 people were identified as being involved in Duncan's care, including the now-sick nurses.
Pham, 26, is being treated at the Dallas hospital and is in good condition. Vinson, 29, who tested positive Wednesday, has been transferred to a high-level biohazard infectious disease centre at Emory University Hospital in Atlanta.
Safety rules have evolved since Ebola was first recognized in 1976 in Zaire. And while there is still no cure, the World Health Organization and Doctors Without Borders have developed relatively safe ways to care for people during many large and deadly outbreaks in Africa over the past four decades.
But Ebola is a new phenomenon in the U.S., providing an opportunity for health officials to revise protocols.
"We need to find out why this transmission occurred, lay open the possibility that the protocol may be inadequate," said Dr. Pascal James Imperato, dean of SUNY's Downstate Medical Center school of public health.
Associated Press writer Jamie Stengle in Dallas contributed to this story.
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