By Katie E. Golden, MD
May 25, 2020
With everyone’s heads turned towards the coronavirus, it can be easy to overlook the other sources of fever and infection that we have to consider. It’s that time of year, with warmer temperatures when Rocky Mountain Spotted Fever (RMSF) becomes more prevalent in the southeastern US. Without vigilance from both patients and doctors alike, this can be a difficult condition to diagnose, and the consequences can be serious. So let’s take a break from viruses, and talk about an entirely different pest – whoever thought a discussion about ticks would be a welcome diversion?!
What is Rocky Mountain Spotted Fever?
RMSF is an infection caused by the bacteria Rickettsia rickettsii. This bacteria is carried by ticks (the ‘vector’), and can be transmitted to humans from the bite of several different species: the Rocky Mountain wood tick, American dog tick, and the Brown dog tick (see pictures below).
We are particularly at risk for these tick bites, which are more prevalent in our region than migrating New York bankers. And for those transplanted Northerners, like myself, RMSF can be thought of as our North Carolina equivalent of Lyme Disease.
How can we protect ourselves from RMSF?
Given the disease is spread by ticks, there are several preventative measures you can take to decrease your risk of exposure:
- Be aware of where ticks live! While they traditionally reside in wooded and grassy areas, urban development means they can be found in nearly any setting. If you have a yard, be sure to clear debris (like leaves, twigs, and brush), and store firewood in a dry, sun-lit area.
- When walking through tick-heavy areas, cover as much of the skin as possible. This means long sleeves, long pants, socks, and close-toed shoes. And while your teenage daughter might shake her head at you, tucking your pants into your socks is a smart idea.
- Use insect repellants. While a controversial product, DEET-containing repellent is most effective at preventing a tick from hitching a ride on an unsuspecting passerby.
- After walking through tick-prone areas, be sure to thoroughly check your skin (as well as your pets). This often requires two people, as ticks are approximately the size of a pinhead and can be easily missed (especially on your back or neck).
- If you find a tick on your body, remove it with tweezers by gently grasping the insect near its head. You do not want to squeeze or crush the tick but instead, pull carefully and steadily so it stays intact. After removal, clean the skin thoroughly (either with soap, or rubbing alcohol). You can then gratifyingly kill the tick (and it’s the bacterial passenger) by soaking it in alcohol or flushing it down the toilet.
Of course, being mindful of the symptoms of RMSF is the next line of defense to ensure it is diagnosed and treated.
What are the symptoms?
RMSF symptoms typically begin 2 to 14 days after the tick bite and can vary from patient to patient. The most common symptoms in the early stages of illness are fever, headache, and a characteristic rash.
The classic RMSF rash develops in most patients (about 90%), and typically starts 2 to 5 days after onset of the fever. It is a spotty, pink, non-itchy rash that can be seen on the arms and legs (wrists, forearms, ankles, palms, and soles), and can sometimes spread inward and include the torso.
Other common symptoms include body aches, fatigue, loss of appetite, nausea, and vomiting, and abdominal pain.
How do you diagnose RMSF?
RMSF can be difficult to diagnose for two reasons: first, the initial symptoms are often vague and can mimic other more common infections, and second, the formal testing is not straightforward. Doctors will, therefore, start treatment based on clinical suspicion alone.
There are two ways to formally diagnose RMSF. Most commonly, a blood test is performed that screens for antibodies, which are proteins that the immune system develops in response to the infection. This immune response, however, takes time, and thus this test can be falsely negative in the early stages of illness. A skin biopsy (in patients who develop the rash) can also be performed, but given the rash develops 5 days after onset of symptoms (if at all), it is not reliable to wait for this diagnosis option.
If RMSF is suspected, doctors will start treatment right away given untreated infection can result in serious complications.
How do you treat RMSF?
RMSF is very treatable when antibiotics are started within the first week of symptoms. Doxycycline, a common and affordable antibiotic, is prescribed for 1-2 weeks and will cure the infection. Without treatment, the infection can lead to dangerous inflammation of the blood vessels in our body. This results in life-threatening dysfunction of our most vital organs (the brain, heart, lungs, and kidneys), and can be fatal. Given the serious consequences of an untreated infection, it is easy to understand why treatment is started early before confirmation of diagnosis.
Okay, now I am scared.
Don’t be – this is a rare condition, with less than 2000 cases reported per year across the entire country. And don’t forget that the prevention and treatment of this condition is relatively easy and straightforward. In addition to the preventative measures we discussed earlier, you should not delay evaluation when you develop symptoms, especially if you suspect you may be at increased risk for a tick bite. (And unlike COVID and the possibility of minimally symptomatic infection, you WILL develop new and noticeable symptoms with RMSF). If you are unable to schedule a last-minute visit with your regular doctor, please do not hesitate to visit an urgent care or emergency room visit to ensure you get the treatment you need in a timely fashion.