VOA常速英语:Questions Remain on Ebola Waste Disposal

Ebola is contracted by coming into contact with the bodily fluids of an infected person. Health workers wear spacesuit-like protective gear when treating patients. But researchers say definitive answers are still needed on how long the Ebola virus can live outside the body. For example, they say more study is needed regarding the liquid medical waste from Ebola patients.

The world’s top health agencies have issued strict protocols on the disposal of solid waste from Ebola Patients. The University of Pittsburgh’s Kyle Bibby said there’s also some guidance on the disposal of liquid medical waste.

“The World Health Organization first issued a statement that it was appropriate to dispose of liquid waste from Ebola patients directly in sanitary sewers or pit latrine without any other treatment. And then the Centers for Disease Control in the U.S. followed that guidance and continues to follow that guidance,” he said.

But when several people in the U.S. were treated for Ebola some questioned whether that guidance offered enough protection.

“There was lots of concern from sewage workers about going down into sewers. Would they be exposed to Ebola? What’s an appropriate personal protective care? So the Centers for Disease Control stated that Ebola survives on the order of minutes in water and is almost instantly or very, very rapidly inactivated. And when we looked to the literature we didn’t find any evidence of that,” he said.

Bibby is an associate professor of civil and environmental engineering. He and colleagues at the University of Pittsburgh and Drexel University did not say the CDC is wrong. They just said that there’s an apparent lack of evidence.

The guidance may be based on the type of virus Ebola is – an enveloped virus. That means it has a membrane or wrapping, which actually comes from an infected cell. But Bibby said enveloped viruses usually don’t fair too well when exposed to liquids. Take the AIDS virus.

“For example, some of the studies that have been done, like on HIV, found that HIV’s survival in water is negligible. It dies very, very quickly. And HIV is an enveloped virus and I think that this is probably one of the lines of evidence that’s been used,” said Bibby.

The National Science Foundation has awarded the researchers a $100,000 grant to study the issue further.

Bibby said, “We don’t have firm guidance and guidelines on disposal of infectious liquid waste, period. And whether that’s from a hospital or funeral homes or other places, other medical facilities, there’s not sort of a concrete guideline on how to dispose of all this.”

Researchers will use viruses that are physically similar to Ebola and test their survival rates in water and wastewater.