TOWN AND COUNTRY • The Marriott St. Louis West hotel will close for several hours Saturday for cleaning after preliminary tests of the hotel's water supply tested positive for Legionnaires' disease, a particularly serious form of pneumonia.

Two unrelated guests of the Marriott were diagnosed with the disease after stays at the hotel at 660 Maryville Drive in October, prompting an investigation by the Missouri Department of Health and Senior Services along with the federal Centers for Disease Control and Prevention.

Officials warned past guests of the hotel that they may have been exposed to Legionnaires' through the hotel's water supply after preliminary tests at the hotel came back positive for Legionella germs in the hotel's cooling tank, which is used for the hotel's showers and drinking water. Officials say more testing is needed before they can confirm the hotel was the source of the germs.