CDC Issues Warning After 3 People Die from a Tick-Borne Disease Known as Rocky Mountain Spotted Fever

“RMSF is endemic across northern Mexico and areas of the southwestern United States,” the CDC said

The Centers for Disease Control and Prevention has announced that an outbreak of Rocky Mountain spotted fever in southern California has led to three deaths.

The bacterial disease is spread through the bite of an infected tick and can cause a headache, fever and rash, according to the CDC.

Per the announcement, there have been a total of five reported cases — all patients had recently been in Tecate, Mexico.

They were diagnosed in late July and suffered from symptoms two weeks after departing Tecate, the CDC said, adding that one was an adult and four were pediatric patients under 18. Children under the age of 10 are five times more likely to die from RMSF than adults, the CDC said.

All five were hospitalized and received treatment in using doxycycline, which is "the treatment of choice for patients of all ages, including young children,” according to the CDC release.

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“RMSF is a rapidly progressive disease and without early administration of doxycycline can be fatal within days,” the CDC added about the disease, which is says often displays “relatively mild and non-specific” signs and symptoms. Those listed by the CDC include a low-moderate fever, headache, gastrointestinal symptoms, abdominal pain, myalgia, rash and edema around the eyes and on the back of hands during the first four days.

Those who have a more advanced diagnosis may develop altered mental status, coma, cerebral edema, respiratory compromise, necrosis and multiorgan system damage on or after the fifth day of illness, according to the CDC. Despite the disease’s name, not every diagnosed patient will immediately develop the "spotted" rash.

Additionally, due to the disease’s rapid progression, around half of patients who die from RMSF “succumb within eight days of illness onset,” per the CDC. “Untreated disease is often fatal, and the case fatality rate of RMSF in Mexico can exceed 40%.”

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“RMSF is endemic across northern Mexico and areas of the southwestern United States,” the CDC stated in the release, identifying the regions of Baja California, Sonora, Chihuahua, Coahuila and Nuevo León as high-risk.

“The pathogen (Rickettsia rickettsii) can be transmitted by brown dog ticks (Rhipicephalus sanguineus) which are closely associated with domestic dogs in urban and peri-urban environments,” the CDC said.

It recommends that people perform “thorough” tick checks on themselves and their dogs and seek medical attention if they — or any member of their family — develops a fever, headache, or rash within two weeks of traveling to Tecate or northern Mexico.

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