When the third child in three months developed a mold infection after heart surgery, Seattle Children’s executives launched an investigation they hoped would be a model for others to follow.

In the spring of 2005, they formed an outbreak response team to pinpoint the source of the infections, reviewed medical charts, swabbed equipment for contaminants and took air samples in operating rooms. They found small amounts of the Aspergillus fungus in and near an operating room, but concluded they were “unlikely to have caused infection.” The main suspect: a dirty nitrogen tank, near an operating room, contaminated with mold.

Children’s was so confident it published the investigation in a journal in 2007 and presented it at a hospital conference. Separately, the hospital fought a nearly three-year court battle opposing claims that its air-handling system caused a 12-year-old girl’s Aspergillus infection.

Last week, in the wake of a recent spate of Aspergillus infections, Children’s Chief Executive Jeff Sperring announced a stunning reversal: Hospital staff now believe the system that circulates air through operating rooms caused mold infections going back to 2001.

That wasn’t the hospital’s only abrupt shift. Shaken by the revelation that at least 14 patients have been sickened and six have died of Aspergillosis, Children’s announced it would install air filters long known to be effective in blocking tiny particles. Sperring said the hospital was moving to “the highest level of filtration found in operating rooms today.” Children’s has closed 10 of its 14 operating rooms until the custom-built filtration systems can be installed.

Children’s repeated struggles to eradicate mold from its operating rooms have forced it to reschedule or delay surgeries, opened it to new litigation and put a cloud over the reputation of the esteemed pediatric hospital.


But the hospital’s disclosures raise questions that executives so far have declined to answer in detail. After infections spanning 18 years and allegations implicating its air-handling system, why has the hospital only now reached this conclusion? Why didn’t the hospital install the superior quality air filters – currently used for three of its operating rooms – for all of them before now?

Lindsay Kurs, a spokeswoman for Children’s, said Monday the hospital had carefully investigated each case in which a patient contracted Aspergillosis after undergoing surgery, but until this year the results were largely inconclusive.

After identifying problems in its air-filtration system in May, Children’s reviewed “historical data” and determined “that these past infections were likely caused by deficiencies in the air-handling systems that serve our operating rooms,” she said.

Based on inspections the hospital conducted in May and November, it believes “gaps between the air filters allowed air to bypass the filters,” Kurs said. Children’s decided in May to install new high-efficiency particulate air – or HEPA – filters in each operating room, and accelerated these plans this month, after detecting Aspergillus again.

“We will conduct a rigorous, thorough review of the factors that led to this situation,” she said, adding that Children’s “will examine our culture, our leadership, and how our teams communicate problems and escalate concerns.”

Susan Mask, chair of Children’s board of trustees, said in a statement Thursday that Sperring has the board’s “full support — and the authority — to do what is necessary to make this right.” She declined to comment on whether the board planned to take disciplinary action against any hospital staff.


The hospital, which reported $196 million in net operating revenue for 2018, declined to provide information on how much the new filtration systems will cost, but said expense was not a factor in the decision to install them.

The retooling for those systems comes as Children’s again confronts allegations in court that it has caused Aspergillus infections.

In late October, the parents of a teenager sued Children’s, alleging the hospital “failed to take reasonably prudent measures to prevent Aspergillus from infecting” their son, leaving him disabled. The infection occurred during brain surgery for a tumor that turned out to be benign, according to Tyler Goldberg-Hoss, a lawyer representing the family.

“The effect on this young man’s life to date has been very substantial, since it happened during his junior year in high school and he lost out on much of his studies and participation in his school’s football team,” Goldberg-Hoss said in a statement. “Although we are in litigation, Seattle Children’s Hospital has been very cooperative in continuing to provide help to our clients to pay for testing, counseling and educational assistance.”

Children’s, which has yet to file a legal response to the lawsuit, has said: “We remain fully committed to working with this family through the legal process and supporting them during what we know is a very difficult time.”

Risk for patients

The risk of Aspergillus infections to hospital patients broadly has been well documented for years.


Most people breathe in the mold daily without getting sick, but patients with lung disease or weakened immune systems — especially organ- or stem-cell-transplant patients — are at higher risk of developing Aspergillosis. In the most serious cases, symptoms range from a fever to coughing up blood, according to the Centers for Disease Control and Prevention (CDC).

A 2009 study looked at more than 60 published outbreaks of hospital Aspergillosis internationally over the previous 40 years and found most of them resulted from construction activities. To protect vulnerable patients from the mold, hospitals employ several defenses in their heating, ventilation and air-conditioning systems.

In a typical hospital HVAC system, air from the outside passes through two sets of filters. The second set is designed to screen out the smallest contaminants. For such tiny particles, HEPA filters are 99.97% effective in blocking particles with a diameter of 0.3 microns or larger, according to infection-control guidelines published by the CDC. The diameter of an Aspergillus spore is about 10 times larger.

Around the same time that Children’s investigated the Aspergillus outbreak in 2005, Eugene and Clarissa Patnode filed a lawsuit alleging that the hospital’s air-filtration system was deficient and had led to an infection that permanently disabled their daughter, then 12 years old. Lawyers for the Patnodes specifically pointed to Children’s lack of HEPA filters as a cause for their daughter’s infection, claiming the hospital’s “filtration system does not filter Aspergillus spores.”

In opposing the claims, Children’s argued in a 2008 court filing that experts hired by the Patnodes couldn’t determine “the number of spores that even allegedly reached the air intakes, much less entered the operating room.” The case settled a few months later. In response to questions from The Seattle Times, Children’s apologized to the Patnode family.

“This was a tragic case for the patient and their family and Seattle Children’s is deeply sorry that recent events have caused them additional grief,” Kurs, the hospital spokeswoman, said by email.


State code, which follows national standards, regulates air filtration in operating rooms but does not require HEPA filters. UW Medicine, which operates Harborview Medical Center and the UW Medical Center, says both hospitals use a combination of HEPA and other high-efficiency filters for their operating rooms.

Installing new filtration systems at a hospital is not as simple as sliding a new air filter into a car, according to infection-control experts. Using a tighter filter can trigger a cascade of changes: a stronger fan to push air through it, a bigger blade for the fan, a wider duct to accommodate the larger blade and more space behind the wall to make room for the larger duct.

“It’s easy to build a new building and just design it that way, but when you’re retrofitting it, you have to go back and redesign the entire air-handling system,” said Dr. David J. Weber, a professor at the University of North Carolina and associate chief medical officer of UNC Health Care. Weber said that when his hospital redesigned an old building to treat stem-cell patients with weakened immune systems, “almost all of the money was re-doing the air-handling units.”

Lawrence Muscarella, an independent consultant and expert on infections in health care facilities, said custom-built filters for each operating room would likely be “extremely expensive” and would require continual monitoring and maintenance.

A history of problems

Allegations of Children’s failures to maintain its HVAC system stretch back more than a dozen years, when former staffers said they found mold in the fan coils and drain pans, and dead birds and droppings plugging the air-intake system, according to court documents in the Patnode lawsuit.

In May, after the hospital notified the Washington state Department of Health that it had detected Aspergillus spores in operating rooms, inspectors cited the hospital for maintenance failures. By then, Children’s had identified six Aspergillus infections in surgical patients in the past two years.


For one air-handling unit serving operating rooms, state inspectors found no documentation that the hospital replaced the prefilters – an apparent reference to the filters that screen out the largest particles – for almost a year, though hospital policy called for doing so at least every three months.

Children’s building operations manager told inspectors that the department “was not currently inspecting, validating or calibrating equipment used to monitor filter performance, air pressure or airflow rates within the facility,” according to the inspection report.

In response, Children’s pledged to audit its maintenance of the operating rooms’ air-handling system every three months until it met its own standards, according to a plan approved by the regulator.

As Children’s faces mounting scrutiny over its response to the Aspergillus infections, it has provided a script to employees with talking points ranging from how to respond to parents anxious about a child’s surgery to statements it has made to media organizations.

Among the questions in a document marked “staff use only”: “Is Seattle Children’s hiding information or lying to the press?” It didn’t definitively answer.

“We took appropriate legal steps to protect the identity of our patients and the confidentiality of our quality improvement information,” the document says. “We continually strive to be transparent and accountable while also honoring the privacy of our patients and families.”

Seattle Times staff reporter Ryan Blethen contributed to this story.