Taken from the New York Times, January 2007.

https://www.nytimes.com/2007/01/22/health/22whoop.html

At Dartmouth the decision was to use a test, P.C.R., for polymerase chain reaction. It is a molecular test that, until recently, was confined to molecular biology laboratories.

“You cannot imagine,” Dr. Talbot said. “I had a feeling at the time that this gave us a shadow of a hint of what it might be like during a pandemic flu epidemic.”

Yet, epidemiologists say, one of the most troubling aspects of the pseudo-epidemic is that all the decisions seemed so sensible at the time.

Nearly 1,000 health care workers at the hospital in Lebanon, N.H., were given a preliminary test and furloughed from work until their results were in; 142 people, including Dr. Herndon, were told they appeared to have the disease; and thousands were given antibiotics and a vaccine for protection. Hospital beds were taken out of commission, including some in intensive care.

Then, about eight months later, health care workers were dumbfounded to receive an e-mail message from the hospital administration informing them that the whole thing was a false alarm.

Not a single case of whooping cough was confirmed with the definitive test, growing the bacterium, Bordetella pertussis, in the laboratory. Instead, it appears the health care workers probably were afflicted with ordinary respiratory diseases like the common cold. Now, as they look back on the episode, epidemiologists and infectious disease specialists say the problem was that they placed too much faith in a quick and highly sensitive molecular test that led them astray.

There are no national data on pseudo-epidemics caused by an overreliance on such molecular tests, said Dr. Trish M. Perl, an epidemiologist at Johns Hopkins and past president of the Society of Health Care Epidemiologists of America. But, she said, pseudo-epidemics happen all the time. The Dartmouth case may have been one the largest, but it was by no means an exception, she said.

There was a similar whooping cough scare at Children’s Hospital in Boston last fall that involved 36 adults and 2 children. Definitive tests, though, did not find pertussis.

“It’s a problem; we know it’s a problem,” Dr. Perl said. “My guess is that what happened at Dartmouth is going to become more common.”

Many of the new molecular tests are quick but technically demanding, and each laboratory may do them in its own way. These tests, called “home brews,” are not commercially available, and there are no good estimates of their error rates. But their very sensitivity makes false positives likely, and when hundreds or thousands of people are tested, as occurred at Dartmouth, false positives can make it seem like there is an epidemic.

“You’re in a little bit of no man’s land,” with the new molecular tests, said Dr. Mark Perkins, an infectious disease specialist and chief scientific officer at the Foundation for Innovative New Diagnostics, a nonprofit foundation supported by the Bill and Melinda Gates Foundation. “All bets are off on exact performance.”

“The big message is that every lab is vulnerable to having false positives,” Dr. Petti said. “No single test result is absolute and that is even more important with a test result based on P.C.R.”

Taken from the New York Times, January 2007.

https://www.nytimes.com/2007/01/22/health/22whoop.html

At Dartmouth the decision was to use a test, P.C.R., for polymerase chain reaction. It is a molecular test that, until recently, was confined to molecular biology laboratories.

“You cannot imagine,” Dr. Talbot said. “I had a feeling at the time that this gave us a shadow of a hint of what it might be like during a pandemic flu epidemic.”

Yet, epidemiologists say, one of the most troubling aspects of the pseudo-epidemic is that all the decisions seemed so sensible at the time.

Nearly 1,000 health care workers at the hospital in Lebanon, N.H., were given a preliminary test and furloughed from work until their results were in; 142 people, including Dr. Herndon, were told they appeared to have the disease; and thousands were given antibiotics and a vaccine for protection. Hospital beds were taken out of commission, including some in intensive care.

Then, about eight months later, health care workers were dumbfounded to receive an e-mail message from the hospital administration informing them that the whole thing was a false alarm.

Not a single case of whooping cough was confirmed with the definitive test, growing the bacterium, Bordetella pertussis, in the laboratory. Instead, it appears the health care workers probably were afflicted with ordinary respiratory diseases like the common cold.

Now, as they look back on the episode, epidemiologists and infectious disease specialists say the problem was that they placed too much faith in a quick and highly sensitive molecular test that led them astray.

There are no national data on pseudo-epidemics caused by an overreliance on such molecular tests, said Dr. Trish M. Perl, an epidemiologist at Johns Hopkins and past president of the Society of Health Care Epidemiologists of America. But, she said, pseudo-epidemics happen all the time. The Dartmouth case may have been one the largest, but it was by no means an exception, she said.

There was a similar whooping cough scare at Children’s Hospital in Boston last fall that involved 36 adults and 2 children. Definitive tests, though, did not find pertussis.

“It’s a problem; we know it’s a problem,” Dr. Perl said. “My guess is that what happened at Dartmouth is going to become more common.”

Many of the new molecular tests are quick but technically demanding, and each laboratory may do them in its own way. These tests, called “home brews,” are not commercially available, and there are no good estimates of their error rates. But their very sensitivity makes false positives likely, and when hundreds or thousands of people are tested, as occurred at Dartmouth, false positives can make it seem like there is an epidemic.

“You’re in a little bit of no man’s land,” with the new molecular tests, said Dr. Mark Perkins, an infectious disease specialist and chief scientific officer at the Foundation for Innovative New Diagnostics, a nonprofit foundation supported by the Bill and Melinda Gates Foundation. “All bets are off on exact performance.”

“The big message is that every lab is vulnerable to having false positives,” Dr. Petti said. “No single test result is absolute and that is even more important with a test result based on P.C.R.”

Taken from the New York Times, January 2007.

https://www.nytimes.com/2007/01/22/health/22whoop.html

At Dartmouth the decision was to use a test, P.C.R., for polymerase chain reaction. It is a molecular test that, until recently, was confined to molecular biology laboratories.

“You cannot imagine,” Dr. Talbot said. “I had a feeling at the time that this gave us a shadow of a hint of what it might be like during a pandemic flu epidemic.”

Yet, epidemiologists say, one of the most troubling aspects of the pseudo-epidemic is that all the decisions seemed so sensible at the time.

Nearly 1,000 health care workers at the hospital in Lebanon, N.H., were given a preliminary test and furloughed from work until their results were in; 142 people, including Dr. Herndon, were told they appeared to have the disease; and thousands were given antibiotics and a vaccine for protection. Hospital beds were taken out of commission, including some in intensive care.

Then, about eight months later, health care workers were dumbfounded to receive an e-mail message from the hospital administration informing them that the whole thing was a false alarm.

Not a single case of whooping cough was confirmed with the definitive test, growing the bacterium, Bordetella pertussis, in the laboratory. Instead, it appears the health care workers probably were afflicted with ordinary respiratory diseases like the common cold. Now, as they look back on the episode, epidemiologists and infectious disease specialists say the problem was that they placed too much faith in a quick and highly sensitive molecular test that led them astray.

There are no national data on pseudo-epidemics caused by an overreliance on such molecular tests, said Dr. Trish M. Perl, an epidemiologist at Johns Hopkins and past president of the Society of Health Care Epidemiologists of America. But, she said, pseudo-epidemics happen all the time. The Dartmouth case may have been one the largest, but it was by no means an exception, she said.

There was a similar whooping cough scare at Children’s Hospital in Boston last fall that involved 36 adults and 2 children. Definitive tests, though, did not find pertussis.

“It’s a problem; we know it’s a problem,” Dr. Perl said. “My guess is that what happened at Dartmouth is going to become more common.”

Many of the new molecular tests are quick but technically demanding, and each laboratory may do them in its own way. These tests, called “home brews,” are not commercially available, and there are no good estimates of their error rates. But their very sensitivity makes false positives likely, and when hundreds or thousands of people are tested, as occurred at Dartmouth, false positives can make it seem like there is an epidemic.

“You’re in a little bit of no man’s land,” with the new molecular tests, said Dr. Mark Perkins, an infectious disease specialist and chief scientific officer at the Foundation for Innovative New Diagnostics, a nonprofit foundation supported by the Bill and Melinda Gates Foundation. “All bets are off on exact performance.”

“The big message is that every lab is vulnerable to having false positives,” Dr. Petti said. “No single test result is absolute and that is even more important with a test result based on P.C.R.”

Faith in Quick Test Leads to Epidemic That Wasn’t

https://www.nytimes.com/2007/01/22/health/22whoop.html