Fleaborne typhus is on the rise in Los Angeles County, with reported cases nearly tripling over the past decade, from 31 in 2010 to 171 in 2022. The disease can be severe but is rarely fatal, and three deaths last year — the first in nearly 30 years in the county — led the US Centers and Disease Control Prevention to investigate.
General signs and symptoms of fleaborne typhus include fever, headache, rash, liver inflammation and low blood platelets. The disease spreads to humans from infected fleas that often live on rodents, opossums, or cats, both pets and feral. It can’t be spread from person to person, the CDC says.
Fleaborne typhus cases have been rising in LA County for the past decade, and the region hit its highest number in 2022. Experts believe that this increase could be due to two factors: increased physician awareness — and diagnosis — of fleaborne typhus, and increased interactions between humans and opossum and cat populations that carry the typhus flea.
For Dr. Umme-Aiman Halai, a medical epidemiologist at the Los Angeles County Department of Public Health and one of the study’s authors, that “big surge” is concerning. She hopes her team’s report raises awareness among health care providers to recognize and treat the disease early.
While there is no vaccine to prevent fleaborne typhus, a specific antibiotic — doxycycline —can treat it. Less than 1% of patients who receive doxycycline die from the bacterial infection.






