(KRON) — A local health department is investigating whether two deadly cases of Legionnaire’s Disease were linked to visits at a Richmond day spa, Contra Costa Health announced on Saturday.

Two patients reportedly visited the Zen Day Spa in Richmond just days before they observed symptoms of their illness. CCH has taken water samples at the spa and will send them to a lab to be analyzed. Anyone who visited Zen Day Spa should be on the lookout for symptoms of Legionnaires’ Disease and should seek immediate medical care if they notice anything unusual, CCH warned.

Legionnaire’s Disease is a bacterial infection that can be found in some fresh water ecosystems. However, the bacteria can also grow in other moist places like showerheads or hot tubs, according to the Centers for Disease Control and Prevention. People contract the illness by breathing in contaminated droplets of water in the air.

Symptoms of the illness include:

  • Cough
  • Shortness of breath
  • Fever
  • Muscle aches
  • Headaches

Legionnaires’ Disease has also been associated with symptoms including diarrhea, nausea, and confusion. Symptoms often begin between two days and two weeks of being exposed, but it can take longer.

Some people are more at risk than others when it comes to Legionnaires’. Those at a higher risk include:

  • People 50 years or older
  • Current or former smokers
  • People with a chronic lung disease (like chronic obstructive pulmonary disease or emphysema)
  • People with weak immune systems or who take drugs that weaken the immune system (like after a transplant operation or chemotherapy)
  • People with cancer
  • People with underlying illnesses such as diabetes, kidney failure, or liver failure