Seattle Medical Center Investigates Deadly Klebsiella pneumoniae Outbreak

The Virginia Mason Medical Center in Seattle, Washington, is investigating an outbreak of Klebsiella pneumoniae bacteria that has caused 33 infections so far.

The latest case was confirmed on May 4. A total of 9 patients have contracted this specific strain of Klebsiella pneumoniae, all of whom have since died. Because all fatalities occurred in patients with complex conditions, it is unknown whether Klebsiella pneumoniae caused or contributed to these deaths.

“Beginning in October 2022, Virginia Mason Medical Center detected an increase in cases of Klebsiella pneumoniae bacteria at our downtown campus,” Sydney Bersante, interim president of Virginia Mason Medical Center, said in a statement. “We immediately implemented increased safety measures, notified patients who had tested positive for the bacteria, and promptly provided treatment where necessary.”

The Klebsiella pneumoniae bacterium naturally lives in our environment, and is frequently among the bacteria found in a healthy human digestive system. However, Klebsiella infections can occur in sick or immunocompromised persons. The patients most at risk include those requiring ventilators or intravenous catheters, and patients who are taking long courses of antibiotics.

Klebsiella pneumoniae is one of many bacteria that is increasingly developing antimicrobial resistance, enabling it to spread rapidly through health care facilities. The bacterium can cause pneumonia, meningitis, bloodstream infections, wound or surgical site infections, and urinary tract infections (UTIs).

The Virginia Mason Medical Center emphasized that the risk of transmission is “very low” for patients, adding that the facility is taking steps such as environmental sampling, updating infrastructure, and reviewing their cleaning and infection prevention protocols.

“We continue to take proactive steps to avoid additional transmission,” said Bersante. “We are continuing to investigate the source of this outbreak jointly with local and state public health partners.”

These health partners include the Washington State Department of Health (DOH), Public Health - Seattle & King County, and the US Centers for Disease Control and Prevention (CDC).

This is a developing situation. Contagion will update this story once more information is available.