The Orange County Mosquito and Vector Control District announced an increased risk of flea-borne typhus in Fullerton as the first human case was reported in January.
Orange County Health Care Agency said in an email to the Daily Titan that the number of human cases of flea-borne typhus between 2013 and 2024 ranged from 11 to 34 per year across Orange County.
As of January 2026, the number of human flea-borne typhus cases in Fullerton is recorded at three, totaling up to 37 across the entire county.
The OCMVCD is taking precautionary measures to reduce the potential exposure, though risks remain low.
According to the OCMVCD’s Director of Communications, Miquel Jacobs, flea-born typhus spreads when humans come in contact with their feces, which may happen when the flea bites and defecates near the wound.
When humans get those bites, they scratch the flea feces into the bite, then catch it, touch their eyes or inhale it.
Flea-borne typhus is a disease caused by a bacterium which fleas contract when they bite an infected animal. While it can spread from flea to flea, these bacteria do not spread from person to person.
Fleas become infected for the rest of their lives when they bite already infected animals, such as rats, cats or opossums.
Symptoms of flea-borne typhus begin within 3-14 days after contact with infected fleas feces.
According to the U.S. Center of Disease and Control, symptoms of flea-borne typhus include fever, chills, body aches, muscle pain, headache, loss of appetite, nausea, vomiting, stomach pain, cough and a rash.
The OCMVCD continues to monitor dead animals in the county, test fleas found on the bodies and report any discovery of flea-borne typhus.
Fullerton Councilmember and public health professor Shana Charles encourages residents to minimize risk.
“You really make sure that you focus on flea control. It’s not just so that your pets can be comfortable. It’s also to keep everybody in the household safe, because those fleas can carry diseases,” Charles said.
To minimize risks, residents are encouraged to regularly inspect their pets and keep flea control up to date.
Jacobs recommends preventive methods such as keeping wild, rodent and feral animals away from pets, removing pet food and other food sources from outside, covering garbage containers, and trimming vegetation around the house. Higher vegetation attracts possums and feral cats around the area.
“This is something you should always be concerned about, and there are different ways that you can help protect yourself and help mitigate the possibility of giving it,” Jacobs said.