MARSHALL COUNTY, Iowa — A dozen more cases of Legionnaires’ disease have been reported in Marshall County over the past few days, putting the total number at 52.

The Iowa Department of Health and Human Services announced an investigation into a group of 21 Legionnaires’ disease cases, and one resulting death, on September 4. Over the past few weeks, the number of cases has continued to grow.

On Friday the Iowa HHS reported 40 cases of Legionaries’ disease, by Sunday morning they had raised that number to 52 cases. As of Sunday, there has still only been one reported death.

Legionnaires’ disease is caused by bacteria that spreads through the inhalation of aerosolized water droplets, such as cooling towers and fountains. Health officials say the disease is not contagious and most healthy people who become exposed do not become sick.

Health officials say individuals with weakened immune systems, chronic respiratory conditions, smokers and those 50 years and older are most likely to experiences severe illness from Legionnaires’ disease.

Common symptoms of Legionnaires’ disease include:

• Fever
• Cough
• Muscle aches
• Chest pain
• Headaches
• Shortness of breath
• Gastrointestinal symptoms, like nausea or diarrhea

The Iowa HHS, Marshall County Public Health Department, and CDC continue their investigation into the disease cluster. For more information on Legionnaires’ disease and the investigation visit the Iowa HHS website.