The third case of Legionnaires’ disease since August was confirmed this week at the Brooke Army Medical Center in Fort Sam Houston, TX, according to multiple news reports.

The sickened employee is the third civilian worker to come down with the serious respiratory illness in Building #15, an administrative building and clinic near the main BAMC hospital.

The two original cases, which were reported in August, had been defined as a “cluster” due to the dates of onset of the illness, according to the Emerging and Acute Infection Disease Guidelines. The announcement of a third case associated with the same facility within a one-year period changes the classification to an “outbreak.”

“The health and safety of our patients and staff is our top priority, and we are working diligently with local and regional public health officials to investigate this matter,” a BAMC spokesperson said. “We are not currently aware of any patients or clients who have moved through building number 15 who are exhibiting symptoms.”

The sickened employee is currently hospitalized, but no additional information was made available due to patient confidentiality laws.

The 200-plus workers and patients are being moved out of Building #15 for the second time since August. They will be relocated to a temporary workspace again as the facility is investigated to try and determine if the building is the source of Legionella bacteria, which causes Legionnaires’ disease.

In August, BAMC Commander Brigadier General Jeff Johnson said all tests of the building came back negative. “The great news is there is no indication of Legionella bacteria,” Johnson said then. “We have a team of experienced, dedicated specialists who have gone the extra mile and we’re very proud of the work they’ve done. The safety of our staff and patients is our utmost concern.”

Cleaning and maintenance of the building were performed, including inspecting and cleaning all HVAC systems, plus the flushing of all water lines and draining of water heaters.

BAMC is the U.S. Army’s largest and busiest medical center, and the Army’s only military Level I trauma center. It also operates the Department of Defense’s only burn treatment facility.

BAMC said its beneficiaries or military personnel who are suffering upper-respiratory or flu-like symptoms should contact their medical provider either at Fort Sam Houston or off-post clinics.

Legionnaires’ disease 101

Legionnaires’ disease is also called Legionellosis and Legionella pneumonia. It is a severe type of pneumonia or lung infection.

According to the Centers for Disease Control and Prevention (CDC), an estimated 25,000 cases of pneumonia due to the Legionella bacteria (Legionella pneumophila) occur each year. Only 5,000 cases are reported, however, because of the disease’s nonspecific signs and symptoms. Ten percent of people infected will die from the infection.

Legionnaires’ disease looks like other forms of pneumonia or even flu. Early symptoms can include:

  • chills
  • fever, which can be 104 or higher
  • headaches
  • loss of appetite
  • muscle aches.

After the first few days, symptoms can worsen to include:

  • chest pain when breathing, called pleuritic chest pain (due to inflamed lungs)
  • confusion and agitation
  • a cough, which may bring up mucus and blood
  • diarrhea (about one-third of all cases result in gastrointestinal problems)
  • nausea and vomiting
  • shortness of breath.

The incubation period – the amount of time between contracting the bacteria and developing symptoms – is usually 2 to 10 days but can be as much as 16 days.