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Health officials in Napa County are investigating an outbreak of Legionnaires' disease after nine confirmed cases were reported this month, county officials announced Friday.
In addition to the nine confirmed cases, county officials have also identified two suspected cases and one "probable" case. All individuals have been hospitalized but there haven't been any deaths, according to the county.
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The cases were reported to Napa County Public Health between July 11 and Wednesday in the cities of Napa and Calistoga. County health officials said it is normal for the county to get one or two reports of the ailment per year, and though these numbers are higher than that, the risk to residents and visitors remains low.
Legionnaires' disease is a type of pneumonia caused by a bacterium called Legionella. It is not spread person-to-person, but is transmitted by breathing in small droplets of water containing the bacteria. The water can come from air conditioners in large buildings (not in home units, which do not use water as a coolant), hot tubs, cooling misters, decorative fountains, and plumbing systems, county officials said.
The microbe can also be ingested through accidental aspiration of tap water into the lungs, which is a greater risk for people who have trouble swallowing.
Napa County announced the first probable monkeypox virus case in a local resident Tuesday morning.
People most at risk for Legionnaires' disease are over 50, may smoke cigarettes, have weakened immune systems, or have chronic health conditions. The disease is treatable with antibiotics, according to the county.
Napa County is currently investigating possible sources of exposure to the bacteria.
It can take up to two weeks for symptoms of Legionnaires' disease to develop, which include pneumonia-like respiratory symptoms such as fever, chills, cough, shortness of breath, muscle aches and headaches.
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Netherlands' goalkeeper Daphne van Domselaar, center, and her teammates react after France's Grace Geyoro failed to score during the Women Euro 2022 quarterfinals soccer match between France and the Netherlands at the New York Stadium in Rotherham, England, Saturday, July 23, 2022. (AP Photo/Jon Super)
People march in Berlin, Saturday, July 23, 2022. Draped in rainbow flags, around 150,000 people were marching for LGBTQ rights at Berlin’s annual Christopher Street Day celebration. Berlin police gave the crowd estimate on Saturday afternoon but said the number could grow into the evening. (Monika Skolimowska/dpa via AP)
Cleveland Guardians' Amed Rosario hits a double during the third inning of a baseball game against the Chicago White Sox in Chicago, Sunday, July 24, 2022. (AP Photo/Nam Y. Huh)
People climb a pole to perform the "Danza del Palo Volador," or Dance of the Flying Pole, a ritual in honor of the town's patron Saint, Santiago the Apostle, in Cubulco, Guatemala, Friday, July 22, 2022, ahead of the Catholic Saint's feast day on July 25. (AP Photo/Moises Castillo)
Children sleep on the floor of a school turned into a shelter after they were forced to leave their homes in Cite Soleil due to clashes between armed gangs, in Port-au-Prince, Haiti, Saturday, July 23, 2022. (AP Photo/Odelyn Joseph)
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A Ukrainian police officer checks the documents of a man and woman riding their bikes, as he patrols during night time curfew, at a check point, in Donetsk region, eastern Ukraine, Friday, July 22, 2022. (AP Photo/Nariman El-Mofty)
Former President Donald Trump reacts before addressing attendees during the Turning Point USA Student Action Summit, Saturday, July 23, 2022, in Tampa, Fla. (AP Photo/Phelan M. Ebenhack)
President Joe Biden speaks virtually during a meeting with his economic team in the South Court Auditorium on the White House complex in Washington, Friday, July 22, 2022. (AP Photo/Andrew Harnik)
Sylvia Carrasquillo reacts as she sits in front of an open fire hydrant in The Bronx section of New York, Friday, July 22, 2022. Dangerously high temperatures threatened much of the Northeast and Deep South as millions of Americans sought comfort from air-conditioners, fire hydrants, fountains and cooling centers. The heat wave is expected to extend into the weekend. (AP Photo/Seth Wenig)
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Kimberly Garcia Leon, of Peru, celebrates after winning the women's 35km race walk at the World Athletics Championships Friday, July 22, 2022, in Eugene, Ore. (AP Photo/Charlie Riedel)
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Anderson Peters, of Grenada, competes in the men's javelin throw final at the World Athletics Championships on Saturday, July 23, 2022, in Eugene, Ore. (AP Photo/Charlie Riedel)
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CHANGES NAME TO INDIA´S SANJU SAMSON - West Indies' Romario Shepherd celebrates dismissing India’s Sanju Samson during the second ODI cricket match at Queen's Park Oval in Port of Spain, Trinidad and Tobago, Sunday, July 24, 2022. (AP Photo/Ricardo Mazalan)
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