Recent Legionnaires’ Disease Outbreaks

26 cases in Spain • November 2021
Since November 5, 2021, health officials have been investigating 26 cases of Legionnaires’ disease in Montmeló and Montornés del Vallés. Water samples have been collected from several cooling towers.

10 cases and 1 death in the Netherlands • November 2021
At least 10 cases of Legionnaires’ disease have been confirmed in Schijndel, a Noord-Brabant town. One of the infected persons has died. Health officials are investigating potential sources, including a local nursing home.

6 cases in Beaverton, Oregon • October 2021
Six residents of the Murray Blvd/Scholls Ferry Road area of Beaverton, Oregon have been diagnosed with Legionnaires’ disease.  An update to the investigation released in November stated that health officials found Legionella bacteria in a local apartment complex’s hot tub, though they still have not determined whether that is the source of the outbreak.

10 cases and 1 death in Long Island, New York • October 2021
The Nassau County health department investigated 10 cases of Legionnaires’ disease that are suspected to have originated within a one-mile radius of a Long Island neighborhood. All 10 were hospitalized and 1 has died. Health officials released an update mid-November stating that they believe the outbreak to be over.

2 cases at a prison in Somers, Connecticut • October 2021
Two inmates were diagnosed with Legionnaires’ disease and treated in a local hospital. They have recovered and returned to the facility.

2 cases and 1 death among restaurant patrons in Massachusetts • October 2021
Two people who had dined separately at the same restaurant in Merrimack Valley were hospitalized with Legionnaires’ disease. One has since died.

18 cases in Harlem, New York • August 2021
18 people from central Harlem were diagnosed with Legionnaires’ disease, each one needing hospitalization.  Local health officials testing all cooling towers in what they called the “cluster area.”  An update released September 22, 2021 by the health department declared the investigation over.  All cooling towers in the area were reported as being disinfected.

7 cases and 1 death in New Brunswick, Canada • August 2021
8 people from the Moncton area were diagnosed with Legionnaires’ disease, 1 of whom has died. The local health department tested 23 cooling towers in the area. Legionella was found in samples from 9 of the 23.

84 cases among adults attending a sports camp in North Carolina – August 2021
84 people attending an adult basketball camp at a university in North Carolina were diagnosed with Legionnaires’ disease. Health officials believe the source of bacteria to be in one of the training rooms.

2 cases in Melbourne, Australia • August 2021
2 residents of Melbourne’s Cranbourne East division were hospitalized due to Legionnaires’ disease in early August. Health officials investigated spas, pools, and cooling towers to determine the source of the outbreak.

4 cases in Maine • August 2021
4 people from Bangor were diagnosed and hospitalized with Legionnaires’ disease. An investigation was launched to determine if there was a connection between the cases.

2 people on a cruise Ship • July-August 2021
2 people who sailed on a cruise ship between July and August were diagnosed with Legionnaires’ disease. The ship was reported to have undergone testing and mitigation before the next cruise was scheduled to depart.

10 cases and 2 deaths in Montreal • June-August 2021
Between June and early August, 10 cases of Legionnaires’ disease were reported to the Montreal Department of Public Health. 2 of the diagnosed persons died. Several cooling towers were inspected.

8 cases in New Jersey • July 2021
The New Jersey Department of Health received reports between July 16 and July 26 of 8 cases of Legionnaires’ disease in Essex County. As of mid-August, health officials’ theory was that people caught the bacteria through “outdoor exposure.”

30 cases in Rhode Island • June-July 2021
Across the state of Rhode Island, 30 people were diagnosed with Legionnaires’ disease between June 2 and July 26. 28 of those were admitted to the hospital and 1 died. A health official opined that the increase in cases over previous years could be due to the reopening of COVID-closed buildings.

49 cases and 2 deaths in the city of Chicago • July 2021
From July 1-23, 49 cases of Legionnaires’ disease – including 2 deaths – were reported in the Chicago area, which is about 3 times the number of cases reported in the same period the last two years. The Chicago Department of Public Health (CDPH) investigated but did not report a common source.

107 cases in Michigan • July 2021
The 107 confirmed cases of Legionnaires’ disease in Michigan during the first weeks in July was 5 to 6 times higher than cases reported over the same period in 2020. Health officials believe the increase was due to a combination of heavy rainfall, hot weather, and stagnant water in buildings reopened after the pandemic.

7 cases and 2 deaths in Germany • July 2021
5 men and 2 women from northern Baden-Wurttemberg were diagnosed with Legionnaires’ disease, 2 of whom died from the infection. Health officials did not find a common source.

2 cases at a hotel in Minnesota • July 2021
Two people were diagnosed with Legionnaires’ disease after staying at a hotel in Albert Lea, Minnesota. Both guests had been in the hotel pool and hot tub area, which the state health department believed to be the source of the bacteria.

2 cases at a senior living center in Oregon • June 2021
Two more cases of Legionnaires’ disease were reported in June among residents of a senior living center in Portland where 10 cases and 1 death occurred in January. The facility’s management working with state and county health officials apparently did not identify and solve the problem.

2 cases among hotel guests in Missouri • April 2021
2 people who stayed at a hotel in Macon in late March were diagnosed with Legionnaires’ disease. State and County Health Departments found Legionella bacteria in the hotel’s hot tub but did not confirm it was the source.

Sports and Fitness Facility in Indianapolis • April 2021
A large gym in Indianapolis closed temporarily after a “few” members were diagnosed with Legionnaires’ disease. The facility has a pool, locker room, and various sports courts.

14 cases in Union County, New Jersey • February 2021
The New Jersey Department of Health investigated 14 cases of Legionnaires’ disease that were confirmed in February. One of the 14, a male in his late 60s, has died.

17 Cases in New South Wales, Australia • January 2021
Health officials in New South Wales urged facility owners to test and clean their cooling towers after 17 cases of Legionnaires’ disease were reported in Sydney and the Illawarra region in January. As of February, the source of the Legionella bacteria had not been identified.

Major Outbreak in Northern Portugal • October 2020 to January 2021
Between late October and mid-January, 88 people near Longa Vida, Porto, in Northern Portugal, were diagnosed with Legionnaires’ disease, 15 of whom have died. Health officials investigated cooling towers and required many of them to be disinfected, but the source was not confirmed.

9 Cases at a Senior Home in Portland, OR • January 2021
Water was shut off in January at a senior home in Portland, Oregon after 9 residents were diagnosed with Legionnaires’ disease, one of whom has died. Other residents had Legionnaires’ symptoms but were not diagnosed via laboratory tests. All the residents were encouraged to move out until the
county health department determined water from the plumbing system was safe to use.

5 cases in New Zealand from Potting Soil • November 2020
Five cases of Legionnaires’ disease thought to be contracted from potting soil were reported in November, four in the Tasman district and one in the Marlborough district. All five were hospitalized. Investigators determined that the likely source of the cases was potting mix or compost.

Hurstville, New South Wales, Australia • November 2020
After two cases of Legionnaires’ disease were diagnosed in Hurstville, Australia, local health officials initiated an investigation of cooling towers near the town center.

8 Cases in Southern Israel • November 2020
Eight people from Dimona, a Negev city in Southern Israel, were diagnosed with Legionnaires’ disease between late October and mid-November. At least three of the patients were in serious condition at the time of the report. A source was not reported.

Prison in Pontiac, Illinois • October 2020
Two inmates at a correctional facility in Pontiac, Illinois were diagnosed with Legionnaires’ disease. The first case was identified in early September. Legionella was not found in water samples initially collected in the investigation.

Senior Citizens Center in Illinois • October 2020
Three residents of a senior citizens center in Pekin, Illinois have been diagnosed with Legionnaires disease. One of the patients has died and one has been discharged from the hospital. Bottled water was provided after Legionella was found in the facility’s water systems.

8 Cases in Montreal • September 2020
Eight people were hospitalized with Legionnaires’ disease in the LaSalle borough of Montreal between September 9 and 22. Health officials investigated some 200 cooling towers but have not identified a source.

West Bromwich, England • September 2020
Health officials believe a common but unidentified source caused 3 confirmed and 6 possible cases of Legionnaires’ disease in West Bromwich, England.

Illinois Prison • September 2020
Two inmates of the Pontiac Correctional Facility were hospitalized with Legionnaires’ disease in September. Both were expected to recover.

4 Community Cases in Illinois • September 2020
Four people in Tazewell County, Illinois were diagnosed with Legionnaires disease July – September. Health officials investigated the cases on the assumption they were related, but a common source was not reported.

New Westminster, BC, Canada, 6 Cases • September 2020
Health officials concluded that 6 cases of Legionnaires’ disease identified in New Westminster, British Columbia from June to early September were related, but a confirmed source was not reported.

4 Cases, 2 Deaths, Hamilton Township, New Jersey • August 2020
Local health officials in New Jersey investigated 4 cases of Legionnaires’ disease contracted between August 18 and 24. Two of the patients have died.

3 Cases from Potting Soil, New South Wales, Australia • May 2020
Three confirmed cases of Legionnaires’ disease in Australia’s NSW Hunter region were attributed to Legionella longbeachae from potting soil the patients had purchased.

4 Cases in Brunswick, Australia • March 2020
4 residents of a Melbourne, Australia suburb contracted Legionnaires’ disease, confirmed on March 23. Several cooling towers were tested and disinfected, but no samples were positive.

2 Cases in Columbus, OH • February 2020
2 cases of Legionnaires’ disease at a nursing and rehab center prompted the county health department to conduct water testing, implement water restrictions, and install new filters in showers, bathrooms, kitchen areas, and ice machines. Tests returned with positive results for Legionella bacteria of a non-pneumophila species.

11 Cases in Hong Kong • February 2020
11 residents of a neighborhood near the Choi Hung MTR Station in Hong Kong contracted Legionnaires’ disease, prompting the testing of four cooling towers, three of which had high levels of Legionella bacteria. All four towers’ operations were suspended for a thorough cleaning and disinfection. Testing of other water systems was not reported.

3 Cases in Redhill, England • February 2020
3 staff members of a mental health clinic in Redhill, England were diagnosed with Legionnaires’ disease. In response, the facility was closed for cleaning and testing. Microbiological filters were added to bathroom faucets and additional measures were taken in other high-risk areas.

5 Cases Among Senior Living Residents in Lake County, IL • February 2020
5 residents of a senior living center in Lake County, Illinois were diagnosed with Legionnaires’ disease. After one of the infected residents died, the state and county health departments began working with a water treatment company to conduct water testing. Legionella was found in a decorative fountain, a fixture in one apartment, a pool filter, and the irrigation system.

Major Outbreak at a Prison in Sumterville, FL • January 2020
At least 23 inmates in a Sumterville, Florida correctional facility were diagnosed with Legionnaires’ disease between January 29 and February 11, 2020. Florida health officials worked with facility representatives to conduct water testing. The facility installed point-of-use filters on showers and faucets, as well as two new recirculating pumps.

2 Cases Among Nursing Home Residents in Plainfield, IL • January 2020
2 patients of a nursing home and rehabilitation center in Plainfield, Illinois were diagnosed with Legionnaires’ disease. Officials from both the county and state health departments investigated the cases, recommending updates be made to the facility’s water management plan. They also suggested they restrict patients’ exposure to water in aerosolized form.

3 Cases in a Retirement Community in Carol Stream, IL • January 2020
3 residents of a retirement community in Carol Stream, Illinois were diagnosed with Legionnaires’ disease from May 2019 through January 2020. The county and state health departments launched investigations into all three cases, which included facility water tests and the implementation of a new water management plan.

2 Cases Among Nursing Home Residents in Chicago, IL • January 2020
2 nursing home residents in Chicago were diagnosed with Legionnaires’ disease. After water samples taken by the nursing home did not show positive for Legionella, the Illinois Department of Public Health (IDPH) took additional water samples. The facility also imposed restrictions on water use and installed new filters.

3 Patients at a Hospital in Winfield, IL • January 2020
3 patients of a hospital in Winfield, Illinois were diagnosed with Legionnaires’ disease. In response, the hospital flushed its plumbing system, conducted water testing, and upgraded its water management plan.

4 Cases in Barrie, Ontario • December 2019
The Simcoe Muskoka District Health Unit reported that 4 cases of Legionnaires’ disease identified among residents of Barrie in December 2019 were not part of the outbreak reported in Orillia two months prior. The health department’s investigation focused on cooling towers, none of which tested positive for Legionella.

3 Cases in Melaque, Mexico • December 2019
3 Americans visiting Melaque, Mexico contracted Legionnaires’ disease in December, 2019. All three patients returned to the U.S. for medical care; it is unknown if the lodging in Melaque collected water samples for testing.

22 Cases in the Bas-Rhin Prefecture, France • November-December 2019
Between November 1 and December 16, 2019, there were 22 confirmed cases of legionellosis in Eastern France, including two patients who died from the infection. All who fell ill were between the ages of 42 and 88.

13 Cases in Elmira, NY • November 2019
There were 13 confirmed cases of Legionnaires’ disease in Elmira, New York. The New York State Department of Health tested a local cooling tower and found the same strain of Legionella that infected the residents. The cooling tower was subsequently shut down for disinfection and remediation.

2 Cases in Hot Springs, AR • November 2019
Legionnaires’ disease was confirmed in two residents of an apartment complex in Hot Springs, Arkansas. Initial testing by the Arkansas Department of Health showed positive Legionella results, with additional testing to be ongoing.

9 Cases in Orillia, Ontario • October 2019
The Simcoe Muskoka District Health Unit (Ontario) conducted testing in early October 2019 after the first of 9 Legionnaires’ disease cases was confirmed in Orillia. All individuals with confirmed cases had spent time recently in the downtown core of Orillia and were over the age of 50 with preexisting conditions. A cooling tower at a sports complex in the city was shut down after it was found to have high levels of Legionella. All municipality-owned cooling towers were also disinfected as a precaution. The definitive source of the outbreak has not been determined. The reports did not mention the investigation of potable water systems.

2 Cases Among Apartment Residents in Salem, MA • October 2019
Legionnaires’ disease was confirmed in two residents of an apartment complex in Salem, Massachusetts. All residents were notified about the cases. After Legionella was found in several samples collected from faucets and showers, residents were advised not to shower and systems were disinfected. Plans were made to replace shower heads and faucet aerators.

2 Cases in Jefferson Parish, LA • October 2019
2 cases of Legionnaires’ diseases were reported at a hospital in Jefferson Parish, Louisiana. After tests of the hospital’s water system returned positive results, several preventive measures were taken, to include closing off patient rooms, testing of all other patients, and disinfection of water systems.

3 Cases Near Columbus, OH • October 2019
A hospital near Columbus, Ohio reported 3 cases of Legionnaires’ disease. While the source was not confirmed, the hospital put in place several water restrictions, to include hyper-chlorination of the water systems.

8 Cases at Pennsylvania NICU • October 2019
8 infants were sickened by Pseudomonas bacteria found in a neonatal intensive care unit (NICU) in a medical center in Danville, Pennsylvania. 3 of the infants died and the rest underwent treatment. Both the CDC and the Pennsylvania Department of Health were involved with the investigation to determine the outbreak’s source, which they believe to have been outside the NICU. In response to the outbreak, the hospital increased water chlorination and installed filters.

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