An illustration of Rickettesia typhi, the bacteria causing the form of typhus that has broken out in Los Angeles.

Recent typhus outbreak could be worse

A mild strain of typhus is spreading in Los Angeles. It could be much worse. Learn about the infectious disease and why it matters.

While some local officials are calling the recent typhus outbreak in Los Angeles an “epidemic,” it’s not as bad as it could be.

As of Monday, 57 people had come down with the flea-born infectious disease in the City of Angels. This strain of typhus is called Murine or endemic typhus, which is caused by an infection with Ricketessia typhi.

After one or two weeks, an infected person may develop fever, headache, chills and muscle aches. Between a quarter and a half of them will develop a rash. Most cases of this type are mild, though it is possible that some will develop severe illness. Doxycyline is an effective antibiotic to treating this type of typhus.

What is typhus?

The history of typhus can be traced back to the Middle Ages, where thousands were devastated during significant periods such as the Napoleonic Wars and the Irish Potato Famine.

Typhus refers to a number of bacterial infections from lice or fleas. According to the Centers for Disease Control and Prevention, only 200 cases of typhus are reported annually. Public health and hygiene make these illnesses rare, especially on the East Coast. The disease is contracted when infected fleas bite humans and/or defecate on exposed skin. Typhus vaccines are not available.

There are three types of typhus:

  • Epidemic/louse-borne typhus: Caused by Rickettsia prowazekii and carried by lice, and possibly ticks. Usually found in areas of high population and poor sanitation, where there is high incidence of lice infestation.
  • Endemic typhus: Rickettesia typhi is the cause of endemic typhus. Found worldwide and mostly among people in close contact with rats. While it isn’t commonly found in the US, there have been reports of cases in Texas and southern California, including the recent outbreak.
  • Scrub typhus: Found in Asia, Australia, Papua New Guinea and the Pacific Islands, this type is caused by Orientia tsutsugamushi and carried by mites in their larval stage.

The current outbreak

As officials are still investigating the cause of the outbreak, some are attributing the rash of typhus cases to Los Angeles’ ballooning homeless population, which has spiked to nearly 55,000 people the past six years. Unsanitary conditions attract fleas and lice, as well as feral cats, opossum and rats, which congregate around garbage and transmit infected fleas.

Keeping garbage away from animals, sealing garbage bins and cleaning up litter prevents this illness from the animals that can thrive on our mess and make us sick.

Why this matters

In May, the CDC reported that vector-borne diseases — such as those contracted from tick, mosquito and flea bites — more than tripled from 2004-2016. Between those years, more than 640,000 cases were reported with nine new germs discovered in the US.

The report suggests that better control of mosquitoes and ticks is necessary to prevent disease from spreading.

Bruce Hirsch, MD, is an infectious disease specialist at Northwell Health and an assistant professor at the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell. He is also a recipient of the Peggy Lillis Foundation Innovator Award for research on clostridium difficille (c-diff).