Eleven former guests at a prominent Atlanta hotel have now been diagnosed with Legionnaires' disease while an additional 55 probable cases have also been linked to the same outbreak, officials said.
"Probable cases" are people who have symptoms of the disease, including diagnosed pneumonia for some, but without laboratory confirmation.
Medical investigators have not yet found the source of the bacterial infection that causes Legionnaires ' -- a serious form of noncontagious pneumonia, said Nancy Nydam, director of communications at Georgia Department of Public Health.
"Based on epidemiological evidence we have an outbreak among people who stayed at the (Sheraton Atlanta) during the same time period," she said. Guests who complained of lung problems and were later diagnosed with Legionnaires' had attended a convention at the Atlanta hotel a couple of weeks ago.
All 11 cases of Legionnaires' disease have been confirmed by testing and no deaths have been reported, said Nydam.
The bacterium causing Legionnaires' has not been confirmed at the hotel, which has hired outside experts to conduct testing. The state health department, the Fulton County Board of Health and environmental specialists are also working with the hotel to test for the bacteria.
The hotel voluntarily closed July 15 and remains closed, Georgia Department of Health stated Monday. More than 400 guests have been relocated to nearby hotels, CNN affiliate WSB-TV reported . Environmental samples were collected on both July 19 and Monday with results pending as testing takes up to 14 days.
"This is the typical way these situations are handled since the assessment and testing can be complicated," according to Nydam. The state health department and other agencies will work with the hotel on the next steps in the investigation.
Thousands infected each year
About one in 10 people who get sick from Legionnaires' disease will die, a recent government report found.
The disease infects an estimated 10,000 to 18,000 people in the United States each year, with some cases not reported to health authorities. The number of people with Legionnaires' disease grew by nearly four times from 2000 to 2014, the CDC stated. People can get sick when they breathe in mist or accidentally take water into their lungs containing the bacteria. It can be treated with antibiotics, according to the US Centers for Disease Control and Prevention.
In addition to relocating current guests to nearby hotels, the Sheraton is also reaching out to guests with upcoming reservations, according to Ken Peduzzi, the hotel's general manager,.
"All guests with upcoming reservations through August 11 have been advised of the hotel's temporary closure and are working with Marriott and Sheraton Atlanta associates to find alternative accommodations. Guests whose reservations have been canceled will receive full refunds," he said, adding that the hotel is also trying to minimize employment disruptions for hotel staff.
James Francey, one of more than 400 relocated guests, told WSB: "This a hazard of travel ... so OK it happens. The CDC is here in town, so that's great."
Symptoms of Legionnaires' disease
Legionnaires' begins with a patient feeling tired and weak, according to the educational organization Legionella.org . Other common symptoms include coughing, diarrhea, nausea, vomiting, headaches, muscle aches, chest pain and shortness of breath. The incubation period -- the time it takes for symptoms to appear after a person is infected with the bacteria causing the disease -- is from 2 to 10 days.
Described as a "severe, often lethal, form of pneumonia," Legionnaires' can lead to treatment in an intensive care unit, according to Legionella.org. Some symptoms may be long-term: One study showed that three quarters of survivors continued to feel tired, 66% had neurologic symptoms and 63% had neuromuscular symptoms months after their diagnosis.
Scientists dubbed the illness "Legionnaires' disease" following an outbreak in Philadelphia in 1976, largely among people attending a state convention of the American Legion.
Legionella bacteria are found naturally in the environment, growing best in warm water, and can be found in shower heads and faucets, hot tubs, cooling towers, hot water tanks, decorative fountains or plumbing systems in large buildings, according to Georgia Department of Health.
In Georgia, 189 cases of Legionnaires' disease were reported in 2018, and 172 cases in 2017.