News Archive
UW Medical Center Legionella update

(10.17 update)
At this time, there have been no cases reported from UW Medical Center since we took steps to eliminate the risk of Legionella in Cascade Tower, including point-of-use filters and hyperchlorination of the water system. The intervening time span is approximately twice the usual incubation period for Legionnaire's disease, suggesting that the outbreak has ended. However, we and Public–Health-Seattle & King County are continuing to monitor to ensure Legionella are not detected in the water system.
(10.7 update)
No new cases have been detected at UW Medical Center since our last report.
Int the Cascade Tower Inpatient Units, all cultures thave ested negative for Legionella bacteria after the hyper-chlorination that was completed Sept. 20. Filters remain in place in the sinks and showers of the inpatient units of the Cascade Tower.
Samples of two scrub sinks in the operating room showed a very low level of Legionella bacteria. We believe that the sinks’ faucets are the source of this very low reading. We are taking these two sinks out of service until a remediation plan is determined.
These sinks are not used by patients.
To check for Legionella bacteria, we continue to have cultures for testing taken from the Cascade Tower water system. As a prevention strategy, supplemental chlorine is being added to the hot water system in the Cascade Tower.
We are updating our water management plan to reflect recently released Centers for Disease Control and Prevention (CDC) national guidelines regarding Legionella.
We continue to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on our Legionella response.
The UW Medicine Information Line for Legionella is available for patients, family members, employees and the general public to contact us with general questions and to reach clinical staff:
1.855.520.2252.
These updates are also avaialble on the UW Medicine webiste, uwmedicine.org.
(9.27 update)
Due to additional investigation, the most recent patient with Legionella at UW Medical Center (UWMC) is believed to have been exposed to the bacteria either in the community or during an earlier hospitalization, prior to the recognition of the Legionella outbreak and before water restrictions and Legionella precautions were implemented at UWMC. The patient had clinically apparent onset of symptoms suggestive of Legionella infection on September 18, two days after the second hospital admission. This means all of the exposure was prior to hyper-chlorination of the UWMC water system Sept.19-20.
Based on this information, water restrictions are not being reinstituted in the Cascade Tower. It is safe to drink and shower from filtered faucets and filtered showers in the inpatient units of the Cascade Tower.
Additional environmental tests have come back positive for the presence of Legionella bacteria in all of the heater-cooler units used in surgery for some cardiac procedures. We reported earlier that three machines were affected and further test results have confirmed Legionella bacteria in all nine machines. However, along with Public Health – Seattle & King County, we believe that the water system in the Cascade Tower is the source of the Legionella infections. (See Public Health Insider blog.)
The heater-cooler units are not thought to be the source of the infections for the following reasons:
- All five patients were housed in the Cascade Tower, where water tested positive for Legionella.
- Heater-cooler units were used in only two of the five cases. UW Medical Center performs about 50 operations a month using the heater-cooler units.
- There have been no confirmed reports of Legionella transmission from heater-cooler units.
- The water in the heater-cooler units does not come into contact with the patient or the patient’s blood at any time.
- Patients in the operating room are on breathing machines (ventilators) during surgery and their air supply is protected and separate from the rest of the operating room air, where the heater-cooler units are.
- The timing of the onset of Legionella infection in the two patients that did have surgery in which heater-cooler units were used was outside of the typical incubation period for Legionella in one case and at the end of that period in the other.
Although the heater-cooler units are not thought to be the source of these infections, we are implementing enhanced cleaning and other measures to ensure the safety of our patients, including the following:
- Instead of using manufacturer recommended quarterly cleaning, units are being drained, cleaned and flushed after each use using a chlorine solution.
- Sterile water is being used in the units.
- Ice made from filtered water is being used for the cooler component of the units.
- We continue to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on water-management efforts and have been in contact with the Food and Drug Administration. We will announce new information as it becomes available.
The UW Medicine Information Line for Legionella is available for patients, family members, employees and the general public to contact us with general questions and to reach clinical staff: 855.520.2252.
(9.26 update)
Legionella bacteria have been detected in a fifth UW Medical Center patient, who is currently in satisfactory condition. Current evidence points to the water system in the Cascade Tower building as the most likely source of the outbreak.
The patient was hospitalized twice in the Cascade Tower in the past month. At this time, we do not know if the patient was exposed during a hospitalization in early September, as an outpatient following discharge, or upon readmission Sept. 16.
UW Medical Center instituted water precautions Sept. 13 and completed hyper-chlorination of the water system in the Cascade Tower on Sept. 20. Special water filters have also been installed in the sinks and showers of the inpatient units of the Cascade Tower.
Our microbiology lab continues to monitor all samples specifically for the Legionella bacteria in patients who have had tests ordered for a lung infection. We continue to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on water management efforts. We will announce new information as it becomes available.
The UW Medicine Information Line for Legionella is available for patients, family members, employees and the general public to contact us with general questions and to reach clinical staff: 855.520.2252. For more information, visit uwmedicine.org.
(9.23 update)
Legionella Cases
- No further cases of Legionella have been identified at UW Medical Center since Sept. 15. The last known case is thought to have been contracted prior to instituting water precautions on Sept. 13.
- Because the typical Legionella incubation is 2-10 days, the likelihood of additional cases continues to decrease.
- The Microbiology lab continues to monitor all samples specifically for Legionella bacteria in patients who have tests ordered for a pulmonary infection.
legionella shower filter
Water Safety
- In the Cascade Tower, it is safe to drink from filtered faucets, and it is safe to shower from filtered showers (see photo, right, of the special water filters used on the sinks and showers in the inpatient units of Cascade Tower).
We continue to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on water management efforts and will announce new information as it becomes available. The UW Medicine Information
Line for Legionella pneumonia continues to be available for patients, family members, employees and the general public to contact us with general questions and to reach clinical staff: 855.520.2252.
(9.21 update)
Hyper-chlorination of the water system in the Cascade Tower of UW Medical Center was completed last night, Sept. 20. This is one of the standard methods for eliminating Legionella bacteria. As a precaution, special water filters have been installed in all sinks of the inpatient units of Cascade Tower and are being installed in all showers of those units. Preliminary test cultures in the Montlake Tower water system are negative for Legionella. We are developing plans for testing and treating our other water systems at the hospital. We continue to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on water-management efforts.
(9.20 situation update)
Four patients hospitalized in the Cascade Tower at UW Medical Center have been diagnosed with Legionella pneumonia; two have died. Legionella bacteria could have been a contributing factor, but an official cause of death has not been determined yet.
We are taking the following steps to ensure the health and safety of our patients, families, visitors and staff:
- We have established a UW Medicine information line for Legionella pneumonia: 855.520.2252.
- We are contacting specific high-risk patients who were hospitalized between Aug. 24 and Sept. 13 in the Cascade Tower to educate them about the signs and symptoms of Legionella pneumonia.
- Preventive antibiotics are being provided to specific high-risk patients based on recommendations from our infectious disease team.
- We are installing special water filters in all sinks and showers in the Cascade Tower. These filters are designed to remove Legionella bacteria from the water.
- We are chemically treating water in the Cascade Tower with a chlorine solution that is circulated through the water system.
- The other patient areas are served by different water systems.
- Our doctors, nurses and other care providers will be monitoring for any patients that develop signs of lung infection and can order special tests for the Legionella bacteria as indicated.
- Our microbiology laboratory is monitoring all samples specifically for the Legionella bacteria in all patients who have had tests ordered for a lung infection.
- We are asking patients to alert their care providers if they have or develop signs and symptoms of a lung infection, such as cough, fever and shortness of breath.
Frequently asked questions
What is Legionella?
Legionella is a type of bacteria that live naturally in fresh water and rarely cause illness. In certain situations, Legionella bacteria can also grow in other water settings, such as showers and faucets, cooling towers, decorative fountains and hot tubs.
How do people get Legionella pneumonia?
- Legionella is almost never transmitted from person to person. People can develop Legionella pneumonia by breathing in small droplets of water (such as steam or mist) that contain the bacteria.
- Legionella bacteria are rarely transmitted by drinking water, washing hands or flushing toilets. Legionella is typically transmitted via inhalation of aerosolized water droplets containing Legionella bacteria, or less commonly via aspiration of drinking water.
- The risk of healthcare workers acquiring Legionella infection in this setting is considered to be low.
What are the symptoms of Legionella pneumonia?
Symptoms are similar to other types of pneumonia, including fever, chills and cough. Some people also have muscles aches and headaches. Symptoms usually begin 2 to 10 days after being exposed to the bacteria.
Who is at risk for getting Legionella pneumonia?
Most people who get exposed to the bacteria will not become sick. Risk factors include:
- People 50 years or older
- Current or former smokers
- People with a chronic lung disease (such as chronic obstructive pulmonary disease or emphysema)
- People with a weak immune system from diseases such as cancer, diabetes, or kidney failure
- People who take drugs that suppress the immune system (after a transplant operation or chemotherapy)
How serious is Legionella pneumonia and what is the treatment?
- Legionella pneumonia is serious, but it can be treated with antibiotics. The biggest risk is to people with weakened immune systems versus the general public. Most people who get sick need care in a hospital but make a full recovery.
- Patients with Legionella pneumonia do not need to be put in isolation because of the unlikelihood of person to person transmission.
What are the procedures for cleaning and sanitizing equipment?
- Cleaning with water is a low-risk activity because it does not normally lead to inhalation of water droplets.
- If you have concerns that cleaning may lead to an excess exposure to droplets, use water from a filtered source or use water from other areas of the hospital.
- If water is required to handle or sanitize home CPAP/BiPAP equipment, we recommend using sterile, bottled or filtered water. When possible, use alternative methods that do not require water to sanitize home CPAP/ BiPAP equipment.
Does the water system in the Cascade Tower pose any risks to patients undergoing dialysis?
No. We employ a series of filters, which effectively removes all bacteria from dialysis solution. Nonetheless, as a preventive measure, inpatients in the Cascade Tower will be transferred to the Montlake Tower to receive their dialysis treatments until such time as the water situation has been resolved.
What other information is available about our environmental systems at UWMC?
- We do not have any evidence at this time that Legionella is present in any water system outside of the Cascade Tower. Air ventilation is not affected in any way.
- We are working with Public Health – Seattle & King County, the Centers for Disease Control and Prevention, and an expert industrial hygienist to find the source of the bacteria and assure the integrity of our water systems.
Should I be concerned?
- We believe the steps taken to limit water exposure on the Cascade Tower have substantially reduced the risk of additional Legionella transmission at UWMC.
- As with other infectious outbreaks in healthcare settings, we ask everyone to practice universal precautions and monitor for signs and symptoms of pneumonia or influenza-like illnesses.
- If you develop signs or symptoms of an illness resembling pneumonia or influenza, you should report the symptoms to your supervisor and seek out medical care.
- Legionella infections can be treated effectively with appropriate antibiotics.
Should visitors to UWMC be concerned?
We believe the likelihood of a visitor acquiring Legionella at UWMC is exceedingly low. Visitors who have or develop symptoms of pneumonia, such as fever and cough with shortness of breath, should contact their healthcare provider to determine whether testing for Legionella infection is advisable.
Where can I get more information?
- Call the UW Medicine information line for Legionella pneumonia: 855.520.2252.
- Patients and family members who have questions or concerns should feel free to discuss them with their care providers.
- Care providers who have further questions or concerns can contact Dr. Estella Whimbey, associate medical director and medical director for infection control: Office: 206.598.0106; Pager: 206.583.9096; Cell Phone: 206. 321.5853.
(9.19 update to hospital staff)
On Monday evening, Sept. 19, we will be treating our Cascade Tower water system with a high dose of chlorine. The purpose of the treatment is to eliminate the legionella from our water system. This is a standard method for eliminating this bacteria. This process will start Monday at approximately 5 p.m. and should be complete by 11 a.m. Tuesday.
During this time we will not be able to use the regular water system in the Cascade Tower. All water used for drinking, personal hygiene and hand washing must come from bottled water. Tap water cannot be used for any reason during this time. Flushing toilets and using the drains in the sinks are still allowed and safe.
We will be providing alternate handwashing supplies and methods during this time including the use of SaniHands and hand gel and water via irrigation bags at designated sinks.
Three pieces of operating room equipment were found to have Legionella bacteria; these are heater/cooler units used to indirectly heat and cool blood during cardiac surgery. The water from these machines does not come into contact with the patient's blood at any point during the perfusion process.
These three units, of 12 total such units, have been thoroughly cleaned and sanitized, and taken out of service as an additional precautionary measure. These units have a sealed component that requires disassembly to clean. The devices' manufacturer will come to UW Medical Center to disassemble and internally clean the three units as well as the nine that did not test positive for Legionella.
(9.16 news release from UW Medicine)
Sept. 16, 2016
Media contacts:
Name: Tina Mankowski
UW Medicine / Media Relations
206.685.3841 or 206.949.1983 / ochs@uw.edu
or Susan Gregg sghanson@uw.edu
UW Medical Center reports fourth case of Legionella bacteria
Sept. 16, 2016 – UW Medical Center reported today that a fourth case of Legionella bacteria has been identified. This patient was hospitalized in the Cascade Tower prior to water restrictions being implemented on Sept. 13. The patient is in satisfactory condition. We continue to take steps to ensure the health and safety of our patients, families, visitors and staff.
Here are steps being taken:
A UW Medicine Legionella pneumonia information line has been established: 855.520.2252. Patients, family members and the public can call this number for general information. Options for more detailed information and for medical providers with clinical or infection prevention questions are also provided.
UW Medical Center will begin contacting specific high-risk patients who were hospitalized between Aug. 24 and Sept. 13 in the Cascade Tower to educate them about signs and symptoms of Legionella pneumonia.
Preliminarily positive Legionella culture results have been received from an ice machine and sink in an operating room hallway of the Cascade Tower and three pieces of operating room equipment that have no direct contact with patients. All have been removed from service, and the ice from the machine was never used for food or drinks.
UW Medical Center will begin chemically treating water in the Cascade Tower early next week with a chlorine solution that is circulated through the water system. Testing of all water systems will continue until they are negative for Legionella.
UW Medical Center continues to work closely with Public Health – Seattle & King County and the Centers for Disease Control and Prevention on water remediation efforts and will announce new information as it becomes available.
(9.16 update)
The Legionella Pneumonia Information Line for UW Medical Center patients and families is 855.520.2252.
"Legionella: What You Need to Know" has been posted online by University of Washington Environmental Health & Safety, UW Health Sciences Admistration. It discusses the UW Medical Cener situation and provides general information on Legionella.
UW Medical Center Legionella Update is a Q & A from the Univeristy of Washington School of Public Health.
(9.15 update)
UW Medical Center has sent the following letter to patients:
UW Medical Center update on Legionella pneumonia
(9.14 update)
On Sept. 13, some initial environmental test results came back positive for Legionella bacteria in several water sources for an inpatient unit at University of Washington Medical Center in Seattle.
UW Medical Center is taking several steps to substantially mitigate the risk of additional Legionella transmission. To date, three patients had been affected.
UW Medical Center is working with its maintenance team, infection control, Public Health Seattle King County, the Centers for Disease Control and an external consultant who is an expert in Legionella remediation to identify the source of this bacteria and to treat the water system. Although the bacteria was discovered in the Cascade Tower, UW Medical Center is continuing to screen all water sources throughout the medical center.
For details about the latest findings on this situation as of Sept. 14, and the plans for moving forward to remediate this situation, watch a re-broadcast of a press conference on your desktop or smartphone on @UWMedicine on Periscope or @UW Medicine Twitter:
https://www.periscope.tv/UWMedicine
https://twitter.com/uwmedicine
Also see details about the situation from Public Health Insider, an information site produced by Public Health Seattle King County:
As a reminder, Legionella bacteria is transmitted via water sources. Legionella is almost never transmitted from person to person.
UW Medicine will provide ongoing updates as new information becomes available.