We use cookies to provide you with a better experience. By continuing to browse the site you are agreeing to our use of cookies in accordance with our Cookie Policy.
An article entitled, “The Importance of Clinical Surveillance in Detecting Legionnaires’ Disease Outbreaks: A Large Outbreak in a Hospital with a Legionella Disinfection System — Pennsylvania, 2011–2012,” published in a scientific journal called Clinical Infectious Diseases doesn’t sound like it would be loaded with personal animosity, office politics and intriguing subplots that all hinge, strangely, over the distinction between “within” and “at.”
But that’s exactly what lies between the lines, if not right in plain sight, throughout the 2015 article written by the Centers for Disease Control and Prevention regarding its investigation of a Legionnaires’ outbreak at a Pittsburgh VA hospital that killed six and sickened 16 others.
Last December, a Pittsburgh Post-Gazette investigation revealed how CDC officials seemed bound and determined to use the tragedy to discredit two former VA researchers internationally recognized for their Legionella studies and the copper-silver ionization system they championed, rather than discover the true cause of the outbreak.
The bias against the researchers and the system is clearly evident in dozens of emails the CDC staff exchanged from the start of the 2012 investigation.
As a result of the newspaper’s two-part series, the CDC was forced to correct the article last June. However, while the issue of whether the copper-silver system did or did not kill Legionella stands corrected, the newspaper also raised two other important concerns that remain as is.
And if you are wondering why it took so long to address the error, that’s how long it took for the CDC to turn over 487 pages of emails following the newspaper’s Freedom of Information Act request.
Personal attacks
“Wait a second … Isn’t this Victor Yu’s/Janet Stout’s former VA hospital?” wrote Cynthia Whitney, the head of the CDC’s respiratory disease department, shortly after the VA first requested help from the agency in 2012 after four people had been infected with Legionnaires’ disease.
(To read all the emails in complete detail, click here.)
Yu and Stout worked together for 26 years at the Pittsburgh VA, building it into one of world’s top Legionnaires’ research centers. The two, who continue to work together at a private lab in Pittsburgh, are best known for their research on Legionella and how it spreads throughout a plumbing system.
And they are just as well known for clashing with the CDC. The two and the agency have disagreed with everything from how Legionnaires’ might be transmitted, to testing protocols, to how to eradicate Legionella.
“There has been a rift for more than 30 years” with the CDC, Yu told the newspaper during its investigation. “It was because they felt they were the gurus, and they were upset when we came up with this ‘ridiculous’ proposal that Legionella came from drinking water instead of cooling towers, and that [we said] you should test your water regularly instead of waiting for someone to get sick first.”
After her first email, Whitney told Stephen Hadler, the CDC’s deputy director of the bacterial disease division and Rana Haijeh, the director of the division and who would approve the investigation, that Yu and Stout “have made long careers from loudly going against CDC’s policies and programs going back decades,” and that they had promoted the copper-silver systems without much evidence.
“So, long story short,” Whitney wrote, “doing this investigation will have a bit of poetic justice to it.”
The emails show that the CDC’s top officials have long favored chlorine systems over copper-silver systems to control Legionnaires’ disease. While there’s naturally bound to be give-and-take among researchers, the exchanges suggest there wasn’t any favorable thoughts given to copper-silver system, despite many hospitals considering it the gold standard to eradicate Legionella.
“Copper-silver ionization, in the absence of adequate total chlorine residual, has not been shown to reliably eradicate Legionella from water systems,” the CDC wrote in the article.
Rather than a professional level of competition and skepticism, the emails can be categorized as either petty office chit-chat, or an outright smear campaign against Yu and Stout.
For example, after a Post-Gazette 2012 article about the outbreak was passed around the CDC via email, Whitney was upset with the references in the story to Yu and Stout.
“I also find it inaccurate in the article that it says Yu and Stout left after a dispute with management, but really they were fired for operating an inappropriate (illegal?) money-making business of Legionella culturing/consultation out of the VA hospital,” Whitney wrote. “Should we let [CDC Director] Dr. [Tom] Friedan know this so he can understand some of their anger toward the hospital? I just don’t think they are going to let this end.”
The two researchers were indeed pushed out of the VA in 2006 in what a Congressional committee later found was a series of unfounded allegations by VA management.
After the CDC’s lead spokesman on the outbreak derided copper-silver systems in a news story, Janet Horsch, an office colleague of Yu and Stout, wrote asking her to clarify the statements.
When Lauri Hicks, the CDC’s Legionnaires’ expert, was shown the email, she told her colleagues: “Beware, Stout and Yu’s lab is fishing for information. We’re not planning to respond, but if they persist, my answer will be that we plan to share our findings in the scientific literature, as soon as possible, where we know the facts will not get distorted. Fun, Fun.”
Hicks would go on to co-author the article.
Some CDC staff even went so far as to question whether the two had any financial stake in the makers of the copper-silver system. (Yu and Stout later told the newspaper during its investigation that they never had any such financial relationships.)
In all, there are 14 emails written by six CDC officials that criticize researchers Yu and Stout between November 2012 and the end of February 2013.
The investigation
Humans being humans, personality clashes are bound to happen. So how about judging the CDC on the merits of its scientific testing and conclusions on this outbreak?
Certainly, the CDC had the right intention when it set out to test the hospital’s copper-silver system. For decades, the system had controlled Legionella, and now it wasn’t. Had Legionella developed a resistance to the method?
To investigate, the CDC put two different strains of Legionella in water at the agency’s Atlanta headquarters testing facility and added copper and silver at three different levels of concentration: the manufacturer’s minimum recommended concentration, the optimal and the maximum.
It then measured how much of the Legionella was, or was not, killed at four different time points: 5 minutes, 30 minutes, 3 hours and 24 hours.
Afterward, CDC researcher Claressa Lucas who conducted the test wrote her colleagues that “at” 24 hours the optimal level of 400 parts per billion of copper and 40 ppb of silver showed a “significant decrease in viability” of the Legionella, but not at the prior time point of three hours.
But that’s not what the CDC reported.
In the article, the CDC writes that its test found that the 400/40 ppb “copper-silver solution, although above the manufacturer’s recommended target concentration for Legionella eradication, failed to reduce viability of any strain within 24 hours.”
Initially, the CDC strongly defended the discrepancy after the newspaper confronted the agency for answers.
“We stand behind the science in the [journal] paper and our investigation into the outbreak,” wrote Kristen Nordlund, a CDC spokeswoman in an email. “At this time, we don’t have anything further to say about the Pittsburgh VA outbreak.”
Lucas also maintained that both her email and the journal article were technically correct.
“The key word in that [journal] sentence is ‘within,’” Lucas wrote in an email response to the Post-Gazette.
She added that is because the last time before 24 hours that she tested for reduced viability was three hours into the test. By then, at three hours, the copper-silver solution had not yet shown significant reduction, and would not show significant reduction until the next test at 24 hours.
As a result, she said, it was accurate to say in the journal article that the copper-silver system had not reduced it significantly “within” 24 hours, even though it did “at” precisely 24 hours.
Got that?
A correction
Eventually, Robert Schooley, the journal’s editor, came calling.
“The way it was written was very misleading,” said Schooley, who was not the journal’s editor when the CDC article was published.
Last June, a correction ran in the journal’s section called “Errata,” which means “an error in printing or writing.”
The correction changed the sentence about the copper-silver testing to read: “In addition, testing at the CDC’s Legionella laboratory revealed that a [200/20 ppb] copper-silver solution at the manufacturer’s recommended target concentration for Legionella eradication failed to reduce viability of any strain within 24 hours, although higher concentrations of [400/40 ppb] or [800/80 ppb] copper-silver were able to significantly reduce Legionella viability at 24 hours.”
Schooley, also told the Post-Gazette having to make such a correction amounts to a retraction of information, and “any retraction is a big deal.”
“It seems here [the CDC employees] had an agenda with the way they did the article from the beginning,” said Schooley, who is also head of the infectious diseases division at the University of California at San Diego.
Stout also told the newspaper this was not an honest mistake.
“The CDC’s 2015 article had an agenda to discredit copper-silver ionization,” she said. “Now we can see the CDC deliberately misrepresented their lab data only to support their view. They took their whole experiment and cherry-picked data.”
If reporting incorrect information wasn’t bad enough, the CDC also contradicted a 2013 VA Inspector General report that blamed the outbreak on poor management in general and poor maintenance in particular of the copper-silver system — not the system itself.
Furthermore, the CDC convinced the VA to make a switch to a chlorine disinfection system.
Finally, the CDC testified in a report to Congress in 2013 with the same erroneous conclusions as would be later printed in the 2015 article.
Two more problems
While the CDC corrected how it reported the performance of the copper-silver system, the newspaper also raised two other problems that remain unchanged.
Sample sites: In both its Congressional report and the article, the CDC said it tested 11 water samples drawn from various spots at the VA during its investigation.
(For a graphic explaining the sampling, click here.)
In seven samples, the agency reported copper-silver levels above the manufacturer’s target levels of 200 ppb copper and 20 ppb silver. And the “mean,” or average concentration of those 11 sites was rounded to 300 ppb for copper and 20 ppb for silver — both at or above the manufacturer’s minimums.
But executives at Liquitech and Enrich, the two companies that, respectively, made and maintained the VA’s copper-silver systems, later told the newspaper four of the 11 sample sites were located “prior to” or “immediately after” copper-silver units in the building.
As a result, the water near the copper-silver units would not be properly circulated and would typically read much higher than, say, a bathroom sink in another part of the hospital.
And that is just what the CDC’s samples showed: Four of the five highest copper readings were from those four sites near the copper-silver systems, and the top two highest silver readings were from there, too.
If those four sites near the copper-silver units were removed from the calculations, the average for copper drops to 240 ppb — just above the manufacturers’ minimum — and the average for silver drops to 15 ppb — below the minimum.
Of the remaining seven samples, four of them had measurements below the manufacturer’s minimums.
More word play: The CDC also reviewed any incidents of Legionnaires’ outbreaks that may have occurred at the hospital prior to its investigation.
According to an email, the agency found 10 cases between 2006 and 2010, although none likely to have originated at the Pittsburgh VA since the same email indicated none of the 10 patients were at the hospital longer than one day.
But the article says this: “Our retrospective review revealed 1 definite and 9 possibly health care association cases of LD associated with VAPHS in 2006-2010.”
How the count went from none to one remains unclear and even contradicts the agency’s own terminology.
The CDC officially defines, a “definite” case of Legionnaires’ only if an analysis of the Legionella bacteria recovered from the patient matched the bacteria found in the hospital’s water; or the patient had been continuously hospitalized for 14 days prior to the onset of Legionnaires’ disease.
Schooley said there still could be further debate or clarification about the CDC’s journal article, but it would have to come through editorial letters from the outside, something he invited anyone to do.