CDC Issues New Health Alert on Rocky Mountain Spotted Fever

The Centers for Disease Control and Prevention (CDC) has reported that three individuals lost their lives after contracting Rocky Mountain spotted fever (RMSF).

Last week, the CDC circulated a health warning detailing five instances of the tick-borne disease that occurred between July and December this year.

Of these five cases, four were children under 18 who had all either lived or vacationed in Tecate, Mexico two weeks prior to falling ill.

The CDC highlighted the extreme danger of RMSF as it's "a severe, rapidly progressive, and often deadly disease" spread through tick bites. All five individuals mentioned in the alert required hospitalization and three later succumbed to the disease.

Thousands of RMSF cases are usually recorded every year in the U.S., but the localized concentration of these cases is a significant worry, Kari Simonsen, MD, MBA, specializing in Pediatric Infectious Diseases at the University of Nebraska Medical Center, informed Health magazine.

She believes that the CDC is sending this warning because this unusual geographic cluster suggests increased RMSF activity via ticks in that area.

Along with warning those living in or visiting Tecate about the risk, the CDC is also prompting healthcare professionals to stay alert for the disease, especially in patients exhibiting severe unexplained symptoms, according to Ann Carpenter, DVM, MPH, an officer in the CDC’s Rickettsial Zoonoses Branch.

The following is what you need to know about the CDC warning, recognizing RMSF, and how to protect yourself from the disease.

Simonsen described that RMSF - similar to Lyme disease - is a bacteria-induced disease transmitted to humans through tick bites.

The Rickettsia rickettsii bacteria, responsible for causing RMSF, can infect a range of tick species. In most parts of the coherent U.S., RMSF is transferred via the American dog tick or the wood tick, explained Carpenter.

Rickettsiosis spotted fever, which encompasses RMSF and several other diseases, is predominantly found in Arkansas, Missouri, North Carolina, Tennessee, Virginia, and nearby regions.

Simonsen stated that the label 'Rocky Mountain' may be a bit misleading as the disease is more prevalent in the southern Appalachian region than the Rockies but has been reported across the country.

In the United States' southwest and northern Mexico, Rickettsia rickettsii bacteria are transmitted by the brown dog tick.

Simonsen highlighted that northern Mexico has seen a rise in RMSF cases in recent years. According to Carpenter, northern Mexico, unlike most of the U.S., has a higher incidence rate, mainly in urban areas, with the brown dog ticket acting as the primary transmitter of RMSF.

In these instances, ticks shift from dogs to humans, and as the CDC highlighted, most spotted fever cases happen within communities with high numbers of stray dogs.

The disease can progress quickly once a person is bitten by an infected tick, manifesting symptoms including:

Simonsen also explained that the rash which marks the disease typically begins at the extremities, namely the wrists and ankles, a characteristic not common in other infection-induced rashes. Over time, the rash moves towards the body's trunk.

The evolution of the rash, which resembles tiny scabs, is an indicator of the infection's progression. Initially, the skin lesions are faint and seem to vanish when pressed upon, but this changes as the disease intensifies.

RMSF symptoms usually remain mild for a few days but can escalate rapidly around the fifth day. Severe RMSF infection can cause coma, tissue death, multi-organ system harm, brain swelling, or altered mental state.

According to Simonsen, children are at an elevated risk of rapid RMSF evolution. Carpenter stated that children under 10 have a five times higher likelihood of succumbing to RMSF than adults.

Given the dangers associated with RMSF, it's crucial to spot the signs of the disease such as the characteristic rash or any apparent tick bites.

However, this is often more complex in reality. Carpenter explained that not all RMSF patients develop the typical spotted rash and many might not even realize they've been bitten by a tick. She further added that early RMSF symptoms can be "relatively mild and nonspecific". Despite this, it's crucial to seek treatment at the onset of mild symptoms, as early intervention greatly improves the outcome.

“The disease progresses rapidly if left untreated and is frequently deadly unless treated with doxycycline within the first 5 days of illness,” said Carpenter. “If RMSF is suspected, health care providers should initiate treatment with doxycycline immediately.”

This antibiotic treatment is effective, Simonsen added, so “don’t wait to go see your doctor and get started on treatment.”

Of course, the best thing to do is avoid RMSF in general—this means avoiding tick bites.

“If you’ve been outside, hiking around, or even just playing in the yard, look for ticks on yourself, and also on kids when they come in from outside,” said Simonsen.

Ticks often move to body creases or the hair since there’s a smaller chance of them being discovered, she added, so it’s worth being thorough.

“Also check your pet for ticks, especially after they spend time outdoors,” Carpenter recommended. “Run your fingers through your pet’s fur with gentle pressure to feel for any small bumps.”

People should also keep up with tick-prevention medications for their dogs, she said.

For humans, using bug spray and wearing protective clothing—such as boots and longer socks if you’re hiking—will help avoid any tick bites, Simonsen said.