Scientists have said for some time that Ebola may be spread through coughing, sneezing [2] and other aerosol transmission.
The top American health agency - the U.S. Centers for Disease Control - has denied this for months. But CDC has finally been forced to admit that it's true.
The Los Angeles Times reports [3] today:
Some scientists who have long studied Ebola say such assurances are premature — and they are concerned about what is not known about the strain now on the loose.
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Dr. C.J. Peters, who battled a 1989 outbreak of the virus among research monkeys housed in Virginia and who later led the CDC’s most far-reaching study of Ebola’s transmissibility in humans, said he would not rule out the possibility that it spreads through the air in tight quarters.
“We just don’t have the data to exclude it,” said Peters, who continues to research viral diseases at the University of Texas in Galveston.
Dr. Philip K. Russell, a virologist who oversaw Ebola research while heading the U.S. Army’s Medical Research and Development Command, and who later led the government’s massive stockpiling of smallpox vaccine after the Sept. 11 terrorist attacks, also said much was still to be learned. “Being dogmatic is, I think, ill-advised, because there are too many unknowns here.”
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“I see the reasons to dampen down public fears,” Russell said. “But scientifically, we’re in the middle of the first experiment of multiple, serial passages of Ebola virus in man…. God knows what this virus is going to look like. I don’t.”
Tom Skinner, a spokesman for the CDC in Atlanta, said health officials were basing their response to Ebola on what has been learned from battling the virus since its discovery in central Africa in 1976. The CDC remains confident, he said, that Ebola is transmitted principally by direct physical contact with an ill person or their bodily fluids. [Well, yes ... everyone knows that physical contact with the victim or their fluids is the prime route of exposure.]
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Finally, some also question the official assertion that Ebola cannot be transmitted through the air. In late 1989, virus researcher Charles L. Bailey supervised the government’s response to an outbreak of Ebola among several dozen rhesus monkeys housed for research in Reston, Va., a suburb of Washington.
What Bailey learned from the episode informs his suspicion that the current strain of Ebola afflicting humans might be spread through tiny liquid droplets propelled into the air by coughing or sneezing.
“We know for a fact that the virus occurs in sputum and no one has ever done a study [disproving that] coughing or sneezing is a viable means of transmitting,” he said. Unqualified assurances that Ebola is not spread through the air, Bailey said, are “misleading.”
Peters, whose CDC team studied cases from 27 households that emerged during a 1995 Ebola outbreak in Democratic Republic of Congo, said that while most could be attributed to contact with infected late-stage patients or their bodily fluids, “some” infections may have occurred via “aerosol transmission.”
Skinner of the CDC, who cited the Peters-led study as the most extensive of Ebola’s transmissibility, said that while the evidence “is really overwhelming” that people are most at risk when they touch either those who are sick or such a person’s vomit, blood or diarrhea, “we can never say never” about spread through close-range coughing or sneezing.
“I’m not going to sit here and say that if a person who is highly viremic … were to sneeze or cough right in the face of somebody who wasn’t protected, that we wouldn’t have a transmission,” Skinner said.
Peters, Russell and Bailey, who in 1989 was deputy commander for research of the Army’s Medical Research Institute of Infectious Diseases, in Frederick, Md., said the primates in Reston had appeared to spread Ebola to other monkeys through their breath.
Will the L.A. Times article finally push the CDC to require respirators for front-line healthcare worker [4]s treating Ebola patients? Or will we need a full pandemic before CDC changes its outdated policy?
The Times’ article also confirms other points we’ve been making:
- Ebola might be contagious even when the victim isn’t showing any symptoms [5]
- Travel screening is a joke [6]