Swine Flu Mask Decision Revisited
LEARN MORE
IMAGE SOURCE: N-95 respirator surgical mask/ NPR Web site
|
The study that led to public policy to use the N-95 respirator surgical masks was based on faulty science.
That was revealed this weekend in Philadelphia when the authors of a study that found the N-95 respirators were better than surgical masks at preventing the flu, retracted the original findings.
The original Australian study, presented earlier this year in San Francisco, formed the basis of the Centers for Disease Control and Prevention (CDC) guidance in using the masks in health care settings, reports ABC News.
The N-95 respirator looks like a surgical mask but is thicker, more expensive fits tighter and filters out at least 95 percent of all viruses.
And they are in short supply after an Institute of Medicine recommendation that health care workers use the N-95 when caring for flu patients. The CDC agreed, putting the N-95 in even shorter supply.
In October, an analysis made at McMaster University in Hamilton, Ontario, found no difference between the N-95 masks and regular surgical masks.
In the Australian study, the nine hospitals were not selected randomly, criticized Mark Loeb of McMaster University. When he reanalyzed the data excluding the control group, the N-95 respirators no longer appeared superior.
The findings are no longer significant said Holly Searle from the University of New South Wales in Australia, retracting the findings at the end of a meeting of the Infectious Diseases Society of America (IDSA).
The author of the original study from the University of new South Wales did not attend the meeting.
The retraction took experts by surprise, though they had been criticized from the beginning.
"We now have public policy that's based on faulty science," said Dr. Neil Fishman of the University of Pennsylvania who attended the meeting, reports ABC News.
"In those early scary days of the new H1N1 influenza, when we were hearing death reports from Mexico, it seemed to make sense that we would take extra precautions with this virus," says Dr. Mark Rupp, president of the Society for Healthcare Epidemiology in America to NPR. "But as we've become more experienced with it and realize that it behaves just like seasonal influenza, it doesn't make as much sense to us anymore."
The flu virus is spread in large droplets and should be blocked by any barrier, even a simple surgical mark barrier. Washing hands, separation of patients with the virus and excluding sick workers and visitors from the hospital are the best ways to avoid transmission.
The U.S. had stockpiled 104 million N-95 respirators from various manufacturers earlier this year and released 25 million when the pandemic was announced. There is currently no plan to replace them. #