California - Legionella Prevention and Costs of Legionnaires Outbreaks

Historical Headlines Related to Legionella

February 22, 2024

According to a recent report, an outbreak of Legionnaires’ disease in downtown Napa that killed one person and hospitalized 16 others in 2022 has been linked to a cooling tower at an unspecified facility. A report from the CDC that examined the disease outbreak contained new information about its possible origin and plans for remediation. A clogged pipe that led to the chemical feed system at the facility impeded the controller’s ability to detect water flow, resulting in low or no injection of biocide — or disinfectant — into the tower. Maintenance records indicated the clog was detected in early July, at about the same time of several cases of exposure. The clog was resolved in early August. The investigation kicked off after Napa County Public Health received three reports of positive tests for the disease on July 11 and 12, 2022. By July 21, six cases had been confirmed among Napa County residents, which compares to an average of one or two cases a year. An environmental health investigation proceeded to identify possible exposure sources within a 1-mile high-risk zone, drawn around a cluster of patients’ residences. The public health agencies then mapped out a total of nine potential sources, including seven cooling towers, a decorative fountain and a produce mister. “Visual inspection, review of records, and sampling of devices within the high-risk zone revealed a lack of maintenance at most cooling towers,” the report says. “Many had low or no detectable chlorine at the time of sampling, because of lack of routine biocide application, improper distribution methods, or other problems with the system.” The five facilities that tested positive for Legionella were notified to remediate their cooling towers, the report says. One required a legal order to shut down a cooling tower because they failed to respond, according to the report. (Source)

December 11, 2023

A spa was closed by the county health department after two people died, and a third was sickened, by Legionnaires’ Disease. The patient who recovered had used the jacuzzi tub at a day spa in the days before falling ill. The spa might have been operating the jacuzzi illegally. According to a statement from the local health department, they “found no existing records indicating the business has ever been issued a permit for a spa or pool." The health department closed the business. (Source)

October 12, 2023

Bay Area officials say they have found the source of an Legionella outbreak that resulted in two deaths. Health officials say they were informed by local hospitals of two deaths from Legionnaires' disease and upon investigation they determined both had recently been to a local day spa. They moved to shut down the spa while conducting the investigation into its water sources for potential legionella bacteria. (Source)

August 24, 2023

After the death of a man from Legionnaire's disease, family and friends are still in shock while they mourn his loss. The family said he contracted the disease after spending five minutes in the hot tub at a day spa. The spa is being investigated after several people showed symptoms of the disease. County Supervisor Joh Giola says the spa was operating illegally and is now closed indefinitely. Two people died from the disease after going to the spa. County health officials are still waiting test results to confirm legionnaire's disease was at the spa. (Source)

June 16, 2023

In San Diego, seven people who got infected with Legionella bacteria died so far this year, according to new numbers provided by the county. The union representing employees in the Mission Valley state building are raising alarm bells about staffer safety after the site recently reopened following the remediation of contaminated areas. The union learned that a custodian’s closet and restrooms on the second floor of the state building tested positive for the bacteria. (Source)

May 26, 2023

“Elevated” levels of Legionella were found at a state building that houses government offices. The new tests on the building in Mission Valley showed elevated levels of Legionella in various faucets according to the California Department of General Services. “We wanted to be safe, so we re-tested the building and then did a remediation.” The elevated levels found are a significant development because previous testing from prior month only showed trace amounts of the bacteria. (Source)

May 10, 2023

Legionella bacteria was found in a state building in February. However, state officials only closed the Mission Valley building to the public and employees after someone inside reported testing positive for the illness in April. According to the department of General Services, Legionella was found in samples during routine testing in February. The deputy director of the Department of General Services said the finding “is typical when testing is performed in large buildings.” She said after receiving a report of a legionella case from someone associated with the building, the state decided to close it while testing and mitigation continues.Source)

May 5, 2023

San Diego State University is reopening its Exercise and Nutritional Sciences (ENS) building after it had been closed for two months for a Legionella pneumonia investigation. A professor in the School of Exercise and Nutritional Sciences was exposed to the bacteria and he later died from it in March. An initial report indicated that the infected individual was quarantined from campus and recovering. (Source)

May 3, 2023

A San Diego County resident developed Legionnaire’s disease in April. This was not long after water pipes in the state-owned building tested positive for “trace amounts” of Legionella. The deputy director of the California Department of General Services confirmed the situation in an email. She said that her department closed the office complex out of an abundance of caution after receiving a report of the new case. She said that her department began doing routine testing for legionella bacteria in 2022 and said that, on the advice of an “expert contractor,” water lines were drained at Metropolitan Drive to “remove legionella” after the inspection. (Source)

April 26, 2023

Jessa Smith is trying to figure out the source where her husband could have gotten sick with Legionnaires' disease after the father of three died. “Nobody knows exactly where he got it from. They’re assuming it’s from (his work) like plumbing because we didn’t get it at our house and he mostly went to work and home,” said Smith. Smith’s husband died on March 1st after spending weeks in the ICU. The plumber was admitted to the hospital with a high fever, fatigue, and shortness of breath. San Diego County says it is aware of 15 cases of the Legionnaires' disease so far this year and three deaths. On Monday, a state building in Mission Valley was closed out of ‘an abundance of caution’ after someone associated with the building was reported to have Legionnaires’ disease. (Source)

April 19, 2023

Longtime journalist Jack Feuer died on April 7. He was admitted to the hospital in Thousand Oaks, California, and was found to be suffering from Legionnaires’ disease which exacerbated underlying medical conditions. Jack Feuer, who was most recently editorial director at UCLA, influenced multitudes of journalists over the years and was truly beloved by many. His stints as a reporter and editor included MediaPost, Adweek and Inside Media magazine. (Source)

April 2, 2023

San Diego State University announced that the water samples collected in the Exercise and Nutritional Sciences Annex building contained a low number of Legionella pneumophila bacterial cultures. The Legionella pneumophila bacteria causes Legionnaires' disease. The bacteria was found in the main ENS building and both buildings have been closed since Feb. 13, when a campus community member was found to have contracted Legionnaires' disease. On March 7, SDSU confirmed that Exercise and Nutritional Sciences professor Michael J. Buono died from the disease. (Source)

March 15, 2023

San Diego State University confirmed the death of professor Michael J. Buono, who contracted Legionella pneumonia in February of 2023. He was the only person with a confirmed case of the illness on campus, which necessitated the closure of the Exercise and Nutritional Sciences building. SDSU said the building will remain closed until the comprehensive testing is completed, which is expected next week. (Source)

February 22, 2023

A San Diego State University "campus community member" was diagnosed with Legionella pneumonia. San Diego State's Exercise and Nutritional Sciences building was temporarily closed while Environmental Health and Safety teams worked closely with San Diego Health & Human Services Agency to identify and confirm the potential source and reports that a community member was diagnosed with Legionella pneumonia. (Source)

February 22, 2023

A lawsuit was filed after a Legionnaires' disease outbreak in Napa. Napa County Public Health detected an unsafe amount of legionella bacteria in a hotel’s cooling tower after a number of people who live nearby became ill. At least a dozen people fell ill and one person died during the outbreak. The lawsuit listed several defendants, including the Embassy Suites in Napa. (Source)

December 7, 2022

A couple contracted Legionnaire's Disease. The couple developed alarming symptoms: exhaustion, diarrhea, chills, vomiting, dizziness, headaches, fever. They slept and slept and slept. They suspected food poisoning as they had recently recovered from a bout of COVID-19, so they didn’t think that was the problem. After several days, one realized the other was struggling to breathe and called 911, although they were so disoriented and exhausted that it took hours to make the call. Doctors eventually diagnosed the couple with Legionnaires’ disease, a rare and serious form of pneumonia. (Source)

December 7, 2022

Nearly two dozen cases of Legionnaires’ disease were identified in the Coachella Valley, going back almost six months. This prompted Riverside County health officials to advise anyone feeling symptoms to seek medical attention. According to the department, 20 cases of Legionnaires’ disease were confirmed since last fall 2021 including two deaths connected to the illness. Officials said the infected patients were residents of Palm Desert, Palm Springs and neighboring communities. The California Department of Public Health is collaborating with the county in seeking to identify potential sources. (Source)

September 9, 2022

A statement issued by the Alliance to Prevent Legionnaires’ Disease stated that outbreaks only comprise a small number of Legionnaires’ Disease cases. According to the CDC, individual, sporadic cases comprise 96% of all Legionnaires’ diagnoses nationwide. If we want to protect people from contracting Legionnaires’ Disease, we must consider implementing a comprehensive approach that brings together proven Legionella control and investigation practices. (Source)

September 2, 2022

A Legionnaires' Disease outbreak in Napa County has now caused one death according to county officials. Twelve cases were reported to Napa County Public Health between July 11 and July 27 in people who live in the city of Napa and in Calistoga. The 12 sickened people were all hospitalized. ( Source)

August 25, 2022

An unsafe amount of Legionella bacteria was detected in a cooling tower at the Embassy Suites Napa Valley. This incident infected a dozen residents and killed one over the last month according to Napa County health officials. According to the California Department of Public Health and the U.S. Centers for Disease Control and Prevention, the tower at the hotel was determined to hold high levels of the bacteria after the investigation. (Source)

August 25, 2022

An outbreak in Napa County of Legionella bacteria has been traced to two more sites. The county announced that a cooling tower in the Embassy Suites Napa Valley hotel was to blame for some of the outbreak. The county discovered "high levels" of the bacteria in a decorative pond at the Embassy Suites as well. The county has also identified the cooling tower in the county Hall of Justice in the city of Napa as a hot spot.

August 25, 2022

Legionella bacteria was found at a hotel spa in San Jose. Santa Clara County health officials confirmed a pool and hot tub were tested at Aloft San Jose Cupertino after a couple staying at the hotel contracted Legionnaires'. The spa is currently closed and is being decontaminated. (Source)

August 18, 2022

An Legionnaires' Disease outbreak in Napa County has caused one death, county officials said. According to Napa County Public Health, twelve cases were reported between July 11 and July 27 in the city of Napa and in Calistoga. The 12 sickened people were all hospitalized. (Source)

July 15, 2022

Senate Bill 1144 (the Safe and Efficient Water Act) passed the Assembly Education Committee by a vote of 5-0 and is now headed to the Assembly Appropriations Committee. Under SB 1144, a Legionella management program is needed for agencies or schools with any covered buildings that use a cooling tower system over ten years old. Routine bacteriological culture sampling and Legionella culture sampling, as well as remediation and disinfection plans are included in the plan. (Source)

June 23, 2022

Senate Bill 1144, the Safe and Efficient Water Act, passed the California Senate by a vote of 35-1. The bill will be heading to the Assembly for policy committee hearings. The water systems at public schools and state agencies must undergo testing to determine the presence of lead and Legionella under SB 1144. The bill will also require schools and agencies to test their water systems for efficiency of water use. If contaminants are found in any plumbing fixture beyond the legal limits, remediation methods such as filters, testing, or full replacement is expected at the earliest practice time, subject to funding. (Source)

May 25, 2022

Due to Legionnaires’ disease and problems with management, the California Health Care Facility (CHCF) has closed down four times then reopened under the stewardship of six different wardens. CHCF was built 10 years ago on 144 acres of state-owned land at the cost of $820 million and is the most expensive medical and mental health subsidiary of the Department of Corrections and Rehabilitation. (Source).

May 25, 2022

The Coachella Valley has had a run of Legionnaire's disease. In the last six months, nearly two dozen cases of Legionnaires’ disease have been identified in the Coachella Valley. (Source)


Multiple cases of Legionnaires' disease surface in Riverside County. The Riverside County Department of Environmental Health has temporarily closed down a number of pools and spas near downtown Palm Springs to test for Legionella bacteria, which can cause Legionnaires’ disease.


The California Department of Corrections and Rehabilitation reported in March 2019 that two inmates had tested positive for Legionella, one who later died.


The Lodge at Sonoma Renaissance Resort confirmed a report that the hotel’s water tested positive for legionella bacteria during the time it was shut down due to county shelter-in-place orders in 2020.


According to Orange County health officials, the number of people diagnosed with Legionnaires’ disease after spending time in Anaheim or Disneyland increased to 22 in the fall of 2017, resulting in Disneyland shutting down two cooling towers that had elevated levels of Legionella bacteria.


A dozen inmates and staff contracted Legionnaire’s disease at San Quentin State Prison in 2015.

Reported Settlements and Jury Awards

The California Occupational Safety and Health Administration (Cal/OSHA) fined Disneyland $33,000, saying the theme park failed to properly maintain cooling equipment, leading three employees to acquire Legionnaires’ disease.

State Cap on Jury Awards

The Medical Injury Compensation Reform Act (MICRA), is a law enacted in California in 1975 in the hope of controlling soaring medical malpractice insurance premiums and ensuring the continuing availability of malpractice insurance coverage. MICRA caps awards for non-economic losses, such as pain or suffering, at $250,000.

Groundwater Temperature Risk Level – High

Overall Liability and Risk for California – High

Yes, ASHRAE 188 is part of the state code

Legionella and Water Management Plan Assistance

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