Beating the clock on ticks and tick-borne illnesses

Tick warning sign in park

Weather conditions this summer are resulting in a very active tick season, especially in the Midwest. And where there are ticks, the diseases they carry are not far behind – ehrlichiosis, Rocky Mountain spotted fever, tularemia, Heartland virus, and Bourbon virus.

Washington University physician and infectious disease clinic medical director Thomas Bailey, MD, explains, “While many people assume that Lyme disease is prevalent in Missouri and southern Illinois, this is a misconception. We are not in an endemic (always present) area for Lyme disease, and routine testing for Lyme disease is discouraged, particularly for chronic, nonspecific symptoms for which a misinterpreted result may lead to inappropriate therapy. However, Lyme disease is present in the upper Midwest.”

Tick-borne diseases for our area include ehrlichia, Rocky Mountain spotted fever, tularemia, Heartland virus, and Bourbon virus. Transmitted by a tick bite, these unwanted souvenirs can be picked up just about anywhere – a walk in the woods, day at the farm, or weekend camping trip.

Here’s a brief rundown of symptoms and treatment for the tick-borne diseases that are most common in the Midwest.


Symptoms can include fever, chills, headache, muscle aches, upset stomach.

Ehrlichiosis is the most common of the tick-borne diseases in our area and needs immediate treatment. In order to prevent severe complications, treatment with doxycycline is often started before the diagnosis is confirmed with a polymerase chain reaction (PCR) blood test.


The early signs and symptoms are not specific to Rocky Mountain spotted fever (RMSF) –including fever and headache. However, the disease can rapidly progress to a serious and life-threatening illness. Symptoms can include fever, headache, rash (usually develops two to four days after fever begins), nausea, stomach pain, muscle pain, lack of appetite.

Dr. Bailey explains, “Rash is a common sign in people who are sick with RMSF – however it often does not appear early and can vary over the course of the illness —  which can make RMSF difficult to diagnose. This is done with antibody blood test. An important caveat is that people can have a positive antibody test for months to years after an infection, and the infection may not be recalled, or may have resolved on its own without being treated. Testing should therefore not be done for chronic, nonspecific symptoms.

RMSF can be life-threatening and early treatment with the antibiotic doxycycline can prevent death and severe illness.”


Tularemia is rare and can be difficult to diagnose, but the most common form is ulceroglandular and usually occurs following a tick or deer fly bite. A skin ulcer appears at the site where the bacteria entered the body. The ulcer is accompanied by swelling of regional lymph glands, usually in the armpit or groin. Tularemia can also be acquired by handling infected rabbits or squirrels. The most severe form of the disease is tularemia pneumonia, which can occur when an infected animal is run over by a mower. 

Antibiotics are used to treat tularemia. Although symptoms may last for several weeks, most patients completely recover.


Bourbon virus was discovered in 2014 and named for Bourbon County, Kansas, where it was first identified, and it is a rare infection.

Symptoms include fever, fatigue, rash, headache, other body aches, nausea, and vomiting. The rash may be very similar to the rash of RMSF. Some patients also experience lower counts of white blood cells that fight infection and help prevent bleeding.

Antibiotics are not effective against viruses — including Bourbon virus, so doctors can only treat the symptoms. Some patients may need to be hospitalized and given intravenous fluids and treatment for pain and fever.


Heartland virus is also an uncommon tick borne infection. Symptoms are often similar to other tick borne illness. It can take up to two weeks for symptoms to appear after an infected tick bite.

Most people infected with Heartland virus experience fever, fatigue, decreased appetite, headache, nausea, diarrhea, and muscle or joint pain. Many are hospitalized because of their symptoms.

As with the Bourbon virus, antibiotics are not effective against the Heartland virus. Doctors can only treat the symptoms. Some patients may need to be hospitalized and given intravenous fluids and treatment for pain and fever.


Dr. Bailey cautions, “See your healthcare provider if you become ill after having been bitten by a tick or having been in the woods or in areas with high brush where ticks commonly live. Because there are so many tick borne illnesses, it is important to be seen and treated by your physician. Do not try to self-diagnose – time is critical to prevent severe and long-term complications – including death.”


Ticks live in wooded areas, low-lying grasslands and yards. It is important to check yourself immediately for ticks after a day in these areas – and have someone else check those parts of your body you can’t easily see, such as your back. Dogs and cats may also bring ticks indoors if they have been outside.

Ticks can’t bite through clothing, so prevention begins with how you and your family dress. When outdoor activities take you into grassy or wooded areas, everyone should wear:

  • Long-sleeved shirts tucked into pants
  • Socks with closed-toe shoes
  • Long pants tucked into socks
  • Light-colored clothing (so ticks can easily be seen)

If possible, always walk on cleared paths and pavement through wooded areas. Showering helps remove unattached ticks, so be sure to shower after all outdoor activities. It may take up to four to six hours for ticks to attach firmly to the skin.

Insect repellents that contain DEET do help, but are not 100% effective. Treating clothing with a product that contains permethrin, which is known to kill ticks on contact is also a deterrent. DO NOT use permethrin directly on the skin.

For more information, or to make an appointment with one of our Washington University infectious disease specialists, please call 314-747-1206.  Physician referral may be required.

Patients are seen at:

Taylor Avenue Building
620 South Taylor, Suite 200
St. Louis, MO 63110

Originally published: August 18, 2021

Updated: April 3, 2023