Kansas City Tuberculosis Outbreak One of the Largest in History
Hospital laboratories are likely to see an increase in test orders for bacteria-borne infections, such as tuberculosis
The tuberculosis outbreak in Kansas City, Kan., is one of the largest in the US within a one-year period over the past several decades. Hospital laboratories are the front line for detecting these types of infectious diseases.
As of June 6, 2025, the number of reported active cases of tuberculosis (TB) since 2024 was 69 with 62 cases in Wyandotte County and seven cases in nearby Johnson County, both in Kansas, according to the latest available data as of this writing from the Kansas Department of Health and Environment.
An active TB infection is one in which patients are symptomatic, in need of immediate treatment, and contagious. These patients have typically had a positive TB blood or skin test and may have had an abnormal chest x-ray or positive sputum smear or culture.
The latest statistics show there are 97 cases of latent TB infections reported in the same counties. Latent TB infections are those where patients are asymptomatic but have had a positive TB test, a normal chest x-ray, and a negative sputum smear.
Although individuals with latent infections cannot transmit the illness to others, these cases may become active without treatment, rendering them potentially dangerous.
“You can think of TB outbreaks like a canary in the coalmine of our public health infrastructure,” David Dowdy, MD, PhD, professor of epidemiology at Johns Hopkins Bloomberg School of Public Health, told The Guardian. “What causes them to happen is a weakening of our public health infrastructure.” (Photo copyright: Johns Hopkins Medicine.)
Cause of Outbreak Remains Unknown
This TB outbreak was first identified in Kansas last year and its origin is unknown. Two people have died from the infection, but the risk to the public remains low.
“It’s definitely more than just a little blip,” David Dowdy, MD, PhD, professor of epidemiology at Johns Hopkins Bloomberg School of Public Health, told The Guardian. “It’s one of the largest outbreaks of tuberculosis that we’ve seen in the country in the past 30, 40, 50 years.”
TB in humans can be caused by two types of mycobacteria: Mycobacterium tuberculosis and Mycobacterium bovis. The former is the most common cause of the disease. The pathogen is airborne and is transmitted via respiratory droplets produced by coughing, sneezing, or speaking.
TB usually attacks the lungs, but other parts of the body can be affected as well. According to the Centers for Disease Control and Prevention, symptoms of the disease include:
- Cough that lasts more than three weeks.
- Coughing up blood or sputum.
- Fever and chills.
- Loss of appetite.
- Weight loss.
- Night sweats.
- Weakness or fatigue.
- Chest pains.
Each patient in the Kansas outbreak has been screened and contact traced. Testing is being provided free of charge. TB is treatable via antibiotics, and more than 85% of infected individuals fully recover with treatment.
TB is Relatively Common
Although curable and preventable, TB is one of the world’s deadliest infectious diseases. According to the World Health Organization, an estimated 10.8 million people contracted TB in 2023, and 1.25 million people died from the disease that year. Fewer than 10,000 of the cases occurred in the US.
“I think the first misconception about TB is that it’s a rare and uncommon disease. We think of it as something that doesn’t really impact us anymore in 2025, but TB has been here, is here, and it’s something that’s relatively common,” said Michael Bernstein, MD, director of pulmonary and critical care at Stamford Health, Stamford, Conn., in the American Journal of Managed Care. “So, the fact that we would see a TB outbreak doesn’t surprise most pulmonologists.”
Clinical laboratories should monitor localized TB outbreaks as they are at the forefront for testing and detecting infectious diseases. Hospital labs may want to prepare for an upsurge in patients arriving with tuberculosis and other bacterial infections in the future.
—JP Schlingman
