New Cases Of Deadly Tick-Borne Disease Detected In CA. Here's What To Know

SACRAMENTO, CA — A California man has been confirmed as the third case ever reported of a rare, potentially fatal disease carried by ticks as the country sees a nationwide surge in ER visits driven by tick bites this year.

The California Department of Public Health confirmed last week the Rickettsia lanei bacteria, a tick-borne disease, was detected in a Northern California resident in April, marking the third case ever reported in California, and the fourth in the United States.

According to the U.S. Centers for Disease and Prevention (CDC), Rickettsia lanei bacteria is a newly-recognized spotted fever group of the rickettsial species that causes severe Rocky Mountain spotted fever–like illness. The bacteria can cause fever, gangrene, coma and brain inflammation.

Rocky Mountain spotted fever is the the deadliest type of Rickettsia lanei bacteria with a fatality rate of up to 10 percent with treatment and up to 30 percent without treatment, according to the CDC.

California health officials told the Los Angeles Times the infected patient "was seriously ill, hospitalized and has since been discharged and is recovering."

CDC data showed the Northeast recorded the most tick bite visits, followed by the Midwest, Southwest, West and South Central regions, respectively, according to the most recent April 12 update.

Nationally, ER visits to treat tick bites are at their highest level since at least 2017, with 71 per 100,000 trips to the ER, compared to an average of about 30 per 100,000 at this time of year.

Ticks carry a plethora of diseases.

According to the CDC, ticks are responsible for 90 percent of all vector-borne diseases. They include Lyme disease, typical in the Northeast, Mid-Atlantic and Midwest regions; Rocky Mountain spotted fever, a problem nationwide; anaplasmosis and ehrlichiosis, which are common in the eastern and southern U.S.; Powassan virus, common in the Northeast and Great Lakes region; and babesiosis, primarily found in the Northeast and upper Midwest.

How To Prevent Tick Bites

The best defense against ticks is to prevent them from biting, the CDC advises:

Know where ticks live. Ticks hang out in grassy, brushy, or wooded areas—and even your backyard.

Avoid high-risk areas. Skip tall grass, leaf litter, and dense brush when possible—and walk in the center of trails.

Use insect repellent. Apply EPA-registered repellents with ingredients like DEET, picaridin, or oil of lemon eucalyptus.

Treat your clothes and gear. Use products with 0.5 percent permethrin on clothing, boots, and camping gear — or buy pre-treated items.

Dress to protect. Wear long sleeves and pants when possible to reduce exposed skin.

Check your clothes after being outside. Ticks can hitch a ride indoors—remove them and tumble dry clothes on high heat to kill any hidden ones.

Shower soon after coming inside. Showering within two hours can help wash off ticks and reduce disease risk.

Do a full-body tick check. Look carefully in hidden spots like:

• Under arms
• Behind ears
• In hair
• Behind knees
• Around the waist
• Between legs

Check pets and gear. Ticks can ride in on dogs, backpacks, and clothing—inspect everything after outdoor time.

Make your yard less tick-friendly. Reduce tick habitat by:

• Clearing leaf litter
• Mowing the lawn
• Creating barriers (wood chips or gravel)
• Keeping play areas away from wooded edges

Patch Local Editor Beth Dalbey contributed to this report.