The following chronology of significant legionellosis outbreaks in the United States is abstracted from Gideon www.GideonOnline.com and the Gideon e-book series. [1,2]   (Primary references available on request)

1949 – An outbreak of presumed Pontiac fever among steam-condenser cleaners was confirmed retrospectively.

1957 – An outbreak (78 cases, 2 fatal) of legionellosis at a packing plant in Austin, Minnesota was confirmed retrospectively.

1965 – An outbreak (81 cases) at a psychiatric hospital in Washington, D.C. was confirmed retrospectively.

1968 – An outbreak of relatively mild legionellosis was associated with a Health Department building in Pontiac, Michigan (thus, “Pontiac fever”).

1974 – An outbreak during a convention of the Independent Order of Odd Fellows in Philadelphia was reported retrospectively in 1978.

1976 – An outbreak (221 cases, 34 fatal) during an American Legion convention in Philadelphia was traced to a contaminated hotel air conditioning system (thus, “Legionnaires’ disease”).

1977 – Outbreaks were reported in Vermont (16 cases, 14 fatal) and Tennessee (27 cases, 3 fatal).

1977 – An outbreak (6 cases) was reported at a medical center in Ohio.

1977 to 1978 – An outbreak (49 cases, 15 fatal) was reported in a medical center in California.

1978 – An outbreak (44 cases) at a hospital in Tennessee was associated with a contaminated air conditioner cooling tower.

1978 – An outbreak (8 cases) was reported at a country club in Georgia.

1979 (publication year) – An outbreak (39 cases) in Indiana may have been related to a local cooling tower.

1979 – An outbreak (13 cases) was associated with a hotel in Wisconsin.

1980 (publication year) – An outbreak of nosocomial legionellosis was reported at a hospital in Pittsburgh, Pennsylvania.

1980 – An outbreak (14 cases) was reported among building site workers in San Francisco, California.

1980 – Outbreaks (85 cases in 2 outbreaks) were reported at a medical center in Burlington, Vermont.

1981 – An outbreak (29 cases, 1 fatal) of community-acquired legionellosis was reported in Iowa.

1981 – An outbreak (34 cases) of Pontiac fever was associated with a whirlpool at a social club in Vermont.

1981 – An outbreak (317 cases) of Pontiac fever due to Legionella feeleii was reported in an automobile plant.

1981 – An outbreak (12 cases) was associated with a single hotel on St. Croix (US Virgin Islands).

1982 – An outbreak (14 cases) of Pontiac fever in Michigan due to Legionella pneumophila serogroup 6 was related to a whirlpool.

1982 – An outbreak (7 cases) in a hospital in New York was associated with a contaminated hot water system.

1983 – An outbreak (15 cases) at a hospital in Rhode Island was associated with a cooling tower.

1983 to 1984 – An outbreak (5 cases) of waterborne Legionella bozemanii infection in New York was reported among immunosuppressed patients.

1984 – An outbreak of Pontiac fever was associated with a cooling tower in an office building in Manhattan, New York.

1985 – An outbreak (14 cases, 3 fatal) followed a church banquet in Michigan.

1986 – An outbreak (27 cases, 2 fatal) was associated with a retail store in Maryland.

1986 – An outbreak (26 cases, 2 fatal) in Wisconsin was associated with a cooling tower.

1988 – An outbreak (34 cases) of Pontiac fever due to Legionella anisa in a California hotel was related to a contaminated fountain.

1989 – An outbreak (33 cases, 2 fatal) of legionnaire’s disease was caused by a contaminated mist machine in a retail store in Louisiana.

1989 – An outbreak of Legionella dumoffii sternal-wound infections in a California hospital was due to postoperative topical exposure to contaminated tap water.

1992 – An outbreak (5 cases) was associated with conventions held at a hotel in the Orlando, Florida, region was ascribed to a contaminated fountain the hotel lobby.

1992 – An outbreak was reported in an intensive care unit.

1993 – Outbreaks (45 cases in 3 outbreaks) in Massachusetts (11 cases), Rhode Island (17 cases) and Michigan (17 cases) were associated with contaminated cooling towers.

1994 – Outbreaks (50 cases) reported during nine cruises aboard a single ship were ascribed to an on-board whirlpool spa.

1994 – An outbreak (28 cases) was reported at a hospital in Connecticut. 81

1994 – An outbreak (29 cases) in Delaware was related to contaminated hospital cooling towers.

1996 – An outbreak (15 cases) was associated with exposure to a hot tub on display in a store in Virginia.

1987 to 1996 – An outbreak (25 cases) of nosocomial legionellosis among transplant cases may have begun as early as 1979.

1995 – An outbreak (22 cases) in Pennsylvania was associated with contaminated hospital cooling towers.

1998 – An outbreak (45 cases) of Pontiac fever was ascribed to a whirlpool at a Wisconsin hotel.

1998 – An outbreak (11 cases, 3 fatal) was associated with a hospital in New York.

1999 – An outbreak (29 cases) in Delaware was ascribed to contaminated cooling towers.

1999 – An outbreak (22 cases of Pontiac fever and 2 of Legionnaire’s disease) was reported at a hotel in Georgia.

1999 – An outbreak (3 cases) was reported among workers at a postal facility in Illinois.

1999 – An outbreak (5 cases, 3 fatal) occurred among patients at a hospital in Maryland.

2000 – Cases of Legionella longbeachae infection were acquired from potting soil in California, Oregon, and Washington.

2000 – An outbreak (20 cases) of Pontiac fever was associated with a hotel whirlpool in Wisconsin.

2000 – An outbreak (15 cases) of Pontiac fever was reported in a sugar beet processing plant in Minnesota.

2000 (publication year) – An outbreak (12 cases) of Legionella micdadei infection was reported among transplant recipients at a hospital.

2001 – An outbreak (10 cases, 4 confirmed, 1 fatal) at an automobile plant in Cleveland, Ohio was traced to a contaminated cooling tower.

2001 to 2008 – An outbreak (35 cases) was reported among residents of a condominium complex in Las Vegas, Nevada.

2002 – An outbreak (16 cases) was reported at a prison in Connecticut.

2002 – An outbreak (5 confirmed cases) was reported at a nursing home in Pennsylvania.

2002 – An outbreak (14 cases) was reported at a building complex in Vermont. 106

2002 – An outbreak (117 cases) of Pontiac fever due to Legionella anisa was reported among patrons at a restaurant in Tennessee.

2002 – An outbreak (68 cases) of Pontiac fever was reported at a hotel spa in Illinois.

2002 – An outbreak (3 cases) was reported among Danish tourists to St. Croix (US Virgin Islands).

2003 to 2004 – An outbreak (8 cases) at a hotel in Maryland was associated with potable water.

2004 – An outbreak (107 cases of Pontiac fever and 6 of legionnaire’s disease) was reported among guests at a hotel in Oklahoma.

2004 – An outbreak (7 cases) of legionellosis was reported at a long term care facility.

2005 – An outbreak (3 cases) of legionellosis was reported at a resort condominium in Maryland.

2005 – An outbreak (12 cases)  at a hospital in New York was ascribed to a contaminated cooling tower.

2005 – An outbreak (2 cases) occurred among men attending an American Legion convention at a hotel in Pennsylvania.

2005 – An outbreak (15 cases, 1 fatal) in South Dakota was related to an ornamental fountain in a restaurant.

2008 – An outbreak (10 cases) was reported at a senior citizen housing facility in New York.

2008 – An outbreak (8 cases, 3 fatal) was reported at a hospital in New Jersey.

2008 to 2010 – An outbreak (9 cases) of legionellosis was reported at a resort in Cozumel, Mexico among tourists from the United States and the Netherlands.

2009 (publication year) – An outbreak (2 cases) of legionellosis in a hospital was related to a contaminated ornamental water fountain.

2009 – An outbreak (4 cases) was reported at a hospital in Georgia.

2009 to 2010 – Outbreaks (52 cases in 12 outbreaks) were associated with contaminated lakes, streams or reservoirs.

2010 – An outbreak (8 cases) in Wisconsin was associated with a decorative fountain in a hospital.

2010 – Outbreaks were reported at an Air National Guard base in Michigan (31 cases) 130 131 and a hospital in Wisconsin (6 cases).

2010 to 2011 – An outbreak (5 cases) was reported among tourists at two resort hotels in the US Virgin Islands.

2011 – An outbreak (200 cases, estimated) of presumed Pontiac fever was reported among guests from multiple countries attending a social gathering in California, U.S.A.

2011 – An outbreak (11 cases, 1 fatal) at a hospital in Ohio was related to contaminated water.

2011 – Outbreaks were associated with hotels in Nevada (6 cases) 138 and Maryland (3 cases, 1 fatal) ; and a shredder in New York State (5 cases).

2011 – An outbreak (3 cases, 1 fatal) was reported in Florida.

2011 to 2012 – An outbreak (22 definite and probable cases, 6 fatal) in a hospital in Pittsburgh, Pennsylvania was related to a potable water system.

2012 – An outbreak was reported in Oregon.

2012 – Outbreaks were associated with hotels in New York State (6 cases) , Pennsylvania 145 and Chicago, Illinois (10 cases, 3 fatal) 146 147 ; a hospital in Pittsburgh, Pennsylvania ; and a contaminated water system at a condominium complex in Maryland.

2013 – Outbreaks were reported in Ohio (retirement community, 39 cases, 6 fatal) , Alabama (nursing home, 11 cases, 0 fatal) , Milwaukee, Pennsylvania (6 cases related to an outpatient-lobby fountain) , Wisconsin (31 cases) and Detroit, Michigan (35 cases).

2014 (publication year) – An outbreak (29 cases) Legionnaire’s disease and Pontiac fever was reported at a military base.

2014 (publication year) – Outbreaks (2 outbreaks) were reported in a geriatric center and high-rise residence for seniors in New Jersey.

2014 – Outbreaks were reported in a hematology / oncology unit in Alabama (9 cases, 2 fatal) , a nursing and rehabilitation facility in North Carolina (8 cases) and a softball tournament in Alabama (40 cases).

2015 – An outbreak (3 cases) was associated with a motel in Washington State.

2015 – An outbreak (100 cases, 10 fatal – to August 7) in New York City was associated with contaminated cooling towers.

References:

1. Berger SA. Infectious Diseases of the United States, 2015. 1208 pages, 483 graphs, 13370 references. Gideon ebooks, https://www.gideononline.com/ebooks/country/infectious-diseases-of-the-united-states/
2. Berger SA. Legionellosis: Global Status, 2015.  99 pages, 110 graphgs, 1009 references. Gideon ebooks, https://www.gideononline.com/ebooks/disease/legionellosis-global-status/

Note that among the major English-speaking countries, rates of legionellosis are highest in Australia and New Zealand [1-3] – see graph:

References:
1. Berger SA. Infectious Diseases of New Zealand, 2012. 413 pp, 136 graphs, 1534 references. Gideon e-books, https://www.gideononline.com/ebooks/country/infectious-diseases-of-new-zealand/
2. Berger SA. Legionellosis: Global Status, 2012. 94 pp, 110 graphs, 840 references. https://www.gideononline.com/ebooks/disease/legionellosis-global-status/
3. Gideon graph tool at https://www.gideononline.com/wp-content/uploads/Gideon-Graphs.pps

Note featured on ProMED

Rates of legionellosis in Italy and surrounding countries have increased dramatically since 2000, while the number of travel-associated cases in Italy has almost tripled during this period. [1,2] See graphs:

A tutorial for the Gideon graph tool is available at https://www.gideononline.com/wp-content/uploads/Gideon-Graphs.pps

References:
1. Berger SA. Infectious Diseases of Italy, 2011. 472 pp, 111 graphs, 2235 references. Gideon e-books, https://www.gideononline.com/ebooks/country/infectious-diseases-of-italy/
2. Berger SA. Legionellosis: Global Status, 2011. 90 pp, 106 graphs, 755 references. Gideon e-books, https://www.gideononline.com/ebooks/disease/legionellosis-global-status/

This post has been discussed on ProMED

Notwithstanding a recent outbreak in Dundee, rates of legionellosis in Scotland have changed little during the past three decades, and continue to be similar to those reported in the United States [see graph]

The following background data regarding Legionnaire’s disease in Scotland are abstracted from the Gideon e-book series. [1,2] (primary references available on request)

Notable outbreaks:
1984 – An outbreak (33 cases, 1 fatal) in Glasgow was ascribed to a contaminated cooling tower.
1985 – An outbreak (16 cases) at a hospital in Glasgow was ascribed to a contaminated cooling tower.
1989 (publication year) – An outbreak (187 cases) of Pontiac fever due to Legionella micdadei was associated with use of a whirlpool in Lochgoilhead.
1994 (publication year) – An outbreak (3 cases) in a hospital was related to a contaminated water main.
1998 – An outbreak (2 cases) was reported among passengers on a Scottish cruise ship.
2004 – An outbreak in West Fife was associated with proximity to sullage tanks.
2008 to 2009 – An outbreak (3 cases) of Legionella longbeachae infection was associated with handling potting soil.

References:
1. Berger SA. Infectious Diseases of Scotland, 2011. 403 pp, 140 graphs. Gideon e-books, https://www.gideononline.com/ebooks/country/infectious-diseases-of-scotland/
2. Berger SA. Legionellosis: Global Status, 2011. 90 pp, 106 graphs. Gideon e-books, https://www.gideononline.com/ebooks/disease/legionellosis-global-status/

Update: Reported in ProMED

Rates of legionellosis in Australia and New Zealand have changed little since 2000, but remain somewhat higher than those of the United States and the U.K. – see graph:

The following background data are abstracted from the Gideon e-book series. 1,2 [primary references available on request]

Time and Place:
In Australia, highest legionellosis rates are reported during March to May.
– Legionella pneumophila infection peaks in summer and autumn, and L. longbeachae in spring.
– 69% of patients are males (1991 to 2000), and 71% of patients are above age 49 (1996).
– 2,170 cases of legionellosis were reported during 1991 to 2000.

L. longbeachae accounts for 22% of isolates nationwide, and is the predominant species in Western Australia (apparently associated with potting soils in South Australia).

22 outbreaks were reported during 1992 to 2000.

Notable outbreaks:
1986 – An outbreak of legionellosis was reported in South Australia.
1987 (publication year) – An outbreak of legionellosis was reported in Wollongong, New South Wales.
1987 – An outbreak (53 cases, 13 fatal) was reported in Illawarra, Southeast Sydney.
1992 – An outbreak (26 cases, 6 fatal) was associated with the Fairfield business district in Sydney.
1996 (publication year) – An outbreak (33 cases) was associated with a hotel car park in Sydney.
1998 (publication year) – An outbreak (11 cases) of community-acquired legionellosis was reported in Western Sydney.
1998 – An outbreak (58 cases, 7 fatal) was reported in Victoria. Of these, a cluster of 18 cases was linked to a contaminated cooling tower in a northern Melbourne suburb.
1998 – Two cases were reported among travelers returning from Bali.
2000 – An outbreak (125 confirmed cases; 2 fatal) was traced to a water cooling tower at the Melbourne Aquarium.
2002 (publication year) – An outbreak (5 cases) of Legionella longbeachae was reported in an intensive care unit.
2005 – An outbreak (12 cases) in the business district of Wollongong, New South Wales was ascribed to a contaminated cooling tower.

References:
1. Berger SA. Infectious Diseases of Australia, 2011. 503 pp. Gideon e-book series, https://www.gideononline.com/ebooks/country/infectious-diseases-of-australia/
2. Berger SA. Legionellosis: Global Status, 2011. 90 pp. Gideon e-book series. https://www.gideononline.com/ebooks/disease/legionellosis-global-status/

A recent outbreak in Madrid reminds us that Spain may well have the highest rate of legionellosis in the World. In the following graph, I’ve compared reported cases per 100,000 population for Spain and other regional countries with those of the United States.

67 specific outbreaks have been described in the World’s literature for the United States, as compared to 37 for Spain; however, the number of outbreaks per million population in Spain (0.80) is over 3.6-fold that for the United States (0.22).

The following chronology of legionellosis outbreaks in Spain is abstracted from the Gideon e-book series. [1,2] (primary references available on request)

1973 – An outbreak (89 cases, 3 fatal) was associated with a hotel in Benidorm.
1978 (publication year) – An outbreak (2 fatal cases) was associated with a hotel in Benidorm.
1983 – An outbreak (35 cases) in Valencia was related to contaminated shower heads and toilet tanks.
1984 (publication year) – An outbreak was reported in Los Castillejos.
1984 – An outbreak (32 cases) was reported among Dutch tourists at a hotel in Pineda de Mar (Barcelona region, Spain).
1988 – An outbreak (56 cases) was reported in Barcelona.
1992 (publication year) – An outbreak (6 cases) in a private apartment building in Zaragoza was associated with potable water.
1992 (publication year) – An outbreak was reported in a hospital in Badalona.
1993 – An outbreak (4 British tourists and 1 French tourist) was reported at a hotel in Spain.
1994 – An outbreak (20 cases) was reported in L’Espluga de Francoli, Tarragona.
1996 – An outbreak (260 cases, 197 hospitalized, 14 fatal) was reported in Madrid region (Alcala de Henares). This was the largest outbreak reported in Europe to date.
1996 – An outbreak (4 cases) was reported among British tourists at a hotel in Minorca.
1998 – An outbreak (3 cases, all fatal) was reported in a hospital in Zaragoza.
1999 – An outbreak (6 cases) was reported among foreign tourists to a spa in Cestona (Guipuzcoa Province).
1999 – An outbreak (7 cases, 1 fatal) was associated with a hotel outbreak in Benidorm.
2000 – An outbreak (70 cases, 2 fatal) was reported in Alcoy (Valencia region).
2000 – An outbreak (28 cases) was associated with a cooling tower in the region of a hospital in Vigo (Galicia).
2000 – An outbreak (54 cases, 17 hospitalized, 3 fatal) was reported in the “La Barceloneta” district of Barcelona.
2001 (publication year) – An outbreak (2 cases, both fatal) was reported among mechanics working on a cargo ship in the port of Barcelona.
2001 – An outbreak of 751 clinical cases (449 confirmed, 2 fatal) was reported in Santa Maria de Gracia (Murcia) – the world’s largest recorded outbreak to that time. The source of infection was an outdoor hospital cooling tower.
2001 – An outbreak (18 cases, 3 fatal) was reported from a hospital in Pamplona. A contaminated hot water system was implicated.
2002 – An outbreak (124 cases, 2 fatal) in Matara, Catalonia was related to a local cooling tower. 43 44 45
2003 – Outbreaks (25 total cases, 1 fatal) were reported in Valencia.
2003 – An outbreak (4 cases) was reported at a spa on Tenerife. An additional suspect case was reported in a Venezuelan visitor to the spa.
2004 – An outbreak (28 confirmed cases, 1 fatal) was reported at a hospital in Zaragoza. Contaminated cooling towers were implicated.
2004 – An outbreak (33 cases, 2 fatal) in Vallarca, Barcelona was caused by a contaminated air conditioning system at a private clinic.
2005 – An outbreak (19 cases, 3 fatal) was reported in Barcelona.
2005 – An outbreak (28 cases, including 21 foreigners – 0 fatal) was associated with a shopping center in Torrevieja.
2005 – An outbreak (55 cases, 3 fatal) was associated with a cooling tower in Catalonia.
2006 – An outbreak (146 cases, 0 fatal) in Pamplona was ascribed to contaminated cooling towers.
2006 – An outbreak (5 cases) was reported among ceramic workers in Castellon.
2006 – An outbreak (12 cases) in Catalonia was related to a contaminated mist machine.
2007 (publication year) – An outbreak of Legionnaires’ disease was reported among immunosuppressed patients at a cancer centre in Barcelona.
2007 to 2008 – An outbreak (3 cases) on a hospital surgical ward was associated with a contaminated oxygen humidifier.
2010 – An outbreak (16 cases) in Alcoy was related to a car-washing machine. This was the 16th outbreak in Alcoy since 1999.
2010 – An outbreak (43 cases) of Pontiac fever was reported in Barcelona.
2009 – An outbreak (11 cases, 1 fatal) in Alcoy was related to exposure to the water tank of a milling machine used in street asphalt repaving.

References:
1. Berger SA. Infectious Diseases of Spain, 511 pp, 2,036 refs. 2010, Gideon e-book series. www.gideononline.com/ebooks/country/infectious-diseases-of-spain/
2. Berger SA. Legionellosis: Global Status, 82 pp, 751 refs. 2010, Gideon e-book series. www.gideononline.com/ebooks/disease/legionellosis-global-status/

A recent outbreak in Alcoy reminds us that rates of legionellosis have been increasing in Spain. The following background data are abstracted from the GIDEON e-book series. [1,2]

Graph 1 summarizes disease incidence and rates per 100,000 population.

Graph Notes:
1. 47 cases were reported in the Balearic Islands during 2001 to 2003.
2. 460 cases were reported among Spanish tourists during 2002 to 2006; 30 in 2005; 73 in 2006.
Individual years:
1993 – Included 57 cases in Cataluna
2003 – 5.82 per 100,000 in the Balearic Islands

As seen in Graph 2, this increase has also affected tourists in Spain.

Graph Notes:
1. 281 cases were acquired by foreign tourists in Spain during 1987 to 1995 – 67% of these from Great Britain. 37% of these were acquired in the Balearic Islands.
2. 627 cases were acquired by foreign tourists in Spain during 1989 to 2001.
3. 6,411 cases of legionellosis were reported during 1999 to 2004 – 565 (9%) involving Spanish travelers, and 426 involving foreign travelers in Spain.
4. 73 travel-associated cases were reported in 2006; 68 in 2007.
Individual years:
2003 – Included nine Spanish citizens touring within Spain.

Legionellosis accounts for 3% of community-acquired pneumonia in Palma de Mallorca (1992 to 1994)

Outbreaks – an overview:
– 1989 to 1998 – 55 outbreaks of legionellosis were reported – 36 of these associated with tourism, 11 nosocomial and 8 community-acquired.
– A single hotel in Benidorm was implicated in the infection of 3 tourists in 1989, 1 in 1990, 2 in 1995, 1 in 1996; 3 in 1997; 8 (1 fatal) in 1998.
– 1990 to 1991 – 54 outbreaks involving 805 cases (and additional 1,358 sporadic cases) were reported.
– 1990 to 2004 – 118 outbreaks involving 690 patients were reported in Catalonia – 35.6% involving water towers, and 14.4% involving water distribution systems in public buildings.
– 1999 to 2001 – Four outbreaks affected over 160 people in Alcoy.
– 2000 – Seven outbreaks were reported – 4 of these nosocomial. An additional 4 clusters were reported among tourists to Spain.
– 2000 – Girona reported 32 cases (3 fatal); Barcelona 48 (1 fatal); Vigo 30 (4 fatal) and Alcala de Henares 249 (11 fatal).
– 2001 to 2003 – 135 cases (10 fatal) in 46 clusters were acquired by European travelers to Spain, including 85 in 2002
– 1999 to 2003 – Eight outbreaks (approximately 300 cases) were reported in Alcoy, Alicante.
– 2003 – 55 outbreaks (247 cases) were reported.

Notable outbreaks:
1973 – An outbreak (89 cases, 3 fatal) was associated with a hotel in Benidorm.
1978 (publication year) – An outbreak (2 fatal cases) was associated with a hotel in Benidorm.
1983 – An outbreak (35 cases) in Valencia was related to contaminated shower heads and toilet tanks.
1984 (publication year) – An outbreak was reported in Los Castillejos.
1984 – An outbreak (32 cases) was reported among Dutch tourists at a hotel in Pineda de Mar (Barcelona region, Spain).
1988 – An outbreak (56 cases) was reported in Barcelona.
1992 (publication year) – An outbreak (6 cases) in a private apartment building in Zaragoza was associated with potable water.
1992 (publication year) – An outbreak was reported in a hospital in Badalona.
1993 – An outbreak (4 British tourists and 1 French tourist) was reported at a hotel in Spain.
1994 – An outbreak (20 cases) was reported in L’Espluga de Francoli, Tarragona.
1996 – An outbreak (260 cases, 197 hospitalized, 14 fatal) was reported in Madrid region (Alcala de Henares). This was the largest outbreak reported in Europe to date.
1996 – An outbreak (4 cases) was reported among British tourists at a hotel in Minorca.
1998 – An outbreak (3 cases, all fatal) was reported in a hospital in Zaragoza.
1999 – An outbreak (6 cases) was reported among foreign tourists to a spa in Cestona (Guipuzcoa Province).
1999 – An outbreak (7 cases, 1 fatal) was associated with a hotel outbreak in Benidorm.
2000 – An outbreak (70 cases, 2 fatal) was reported in Alcoy (Valencia region).
2000 – An outbreak (28 cases) was associated with a cooling tower in the region of a hospital in Vigo (Galicia).
2000 – An outbreak (54 cases, 17 hospitalized, 3 fatal) was reported in the “La Barceloneta” district of Barcelona.
2001 (publication year) – An outbreak (2 cases, both fatal) was reported among mechanics working on a cargo ship in the port of Barcelona.
2001 – An outbreak of 751 clinical cases (449 confirmed, 2 fatal) was reported in Santa Maria de Gracia (Murcia) – the world’s largest recorded outbreak to that time. The source of infection was an outdoor hospital cooling tower.
2001 – An outbreak (18 cases, 3 fatal) was reported from a hospital in Pamplona. A contaminated hot water system was implicated.
2002 – An outbreak (124 cases, 2 fatal) in Matara, Catalonia was related to a local cooling tower.
2003 – Outbreaks (25 total cases, 1 fatal) were reported in Valencia.
2003 – An outbreak (4 cases) was reported at a spa on Tenerife. An additional suspect case was reported in a Venezuelan visitor to the spa.
2004 – An outbreak (28 confirmed cases, 1 fatal) was reported at a hospital in Zaragoza. Contaminated cooling towers were implicated.
2004 – An outbreak (33 cases, 2 fatal) in Vallarca, Barcelona was caused by a contaminated air conditioning system at a private clinic.
2005 – An outbreak (19 cases, 3 fatal) was reported in Barcelona.
2005 – An outbreak (28 cases, including 21 foreigners – 0 fatal) was associated with a shopping center in Torrevieja.
2005 – An outbreak (55 cases, 3 fatal) was associated with a cooling tower in Catalonia.
2006 – An outbreak (146 cases, 0 fatal) in Pamplona was ascribed to contaminated cooling towers.
2006 – An outbreak (5 cases) was reported among ceramic workers in Castellon.
2006 – An outbreak (12 cases) in Catalonia was related to a contaminated mist machine.
2007 (publication year) – An outbreak of Legionnaires’ disease was reported among immunosuppressed patients at a cancer centre in Barcelona.
2007 to 2008 – An outbreak (3 cases) on a hospital surgical ward was associated with a contaminated oxygen humidifier.

References:
1. Berger SA. Infectious Diseases of Spain, 516 pp. Gideon Informatics, Inc. 2010, https://www.gideononline.com/ebooks/country/infectious-diseases-of-spain/
2. Berger SA. Legionellosis: Global Status, 84 pp. Gideon Informatics, Inc. 2010, https://www.gideononline.com/ebooks/disease/legionellosis-global-status/