Los Angeles County public health officials identified 220 flea-borne typhus cases in 2025, the highest annual total in the county’s recent run of rising infections. Nearly 9 out of 10 people infected this year required hospitalization, and health officials identified three localized outbreaks in central Los Angeles, Santa Monica and Willowbrook near Compton.
The disease is caused by the bacterium Rickettsia typhi, which spreads when fleas bite infected animals such as rats, stray cats or opossums and then pass the infection to people. In some cases, humans are exposed when flea feces is rubbed into cuts or scrapes on the skin or into the eyes. The county recorded 187 cases in 2024, 124 in 2023, 171 in 2022 and 141 in 2021, showing a steady climb since 2021 despite a dip in 2023.
The case count also spans a wide age range, from 1 to 85, underscoring that the infection is not limited to one group. People who live outdoors or in housing infested with rats or other rodents face the highest risk, and fleas that spread typhus are commonly found on stray animals, rodents and other wildlife. Infectious cases can turn up year-round, but they tend to peak in late summer and fall, when warmer weather increases flea activity.
The pattern is drawing renewed attention because the county’s 2025 totals already eclipse every recent year on record. Public health officials are warning pet owners to take precautions for themselves and their animals, especially since infected fleas can be carried indoors on pets or other animals and spread without being noticed. The rise leaves one clear conclusion: flea-borne typhus is no longer a background illness in Los Angeles County, but a growing public health problem that is now sending a large share of patients to the hospital.
