Relapsing Fever: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Relapsing Fever?
A primary care doctor, such as a family medicine or internal medicine doctor, usually manages relapsing fever from start to finish. In complicated cases, they may work with an infectious disease specialist. A pregnant patient may also see an obstetrician.
What it is
Relapsing fever is an infection caused by spirochetes, thin, corkscrew-shaped bacteria. People get sudden fevers that last a few days, go away, and then come back. Each return of fever is called a relapse. The illness can be serious, but it usually responds well to antibiotics, drugs that kill bacteria.
Symptoms
The first sign is often a high fever that starts suddenly, with chills, headache, muscle aches, nausea, and vomiting. After a few days the fever drops, and the person may feel better for days or even a week before it returns. Without treatment, these cycles can repeat several times. During a fever, some people develop a rash, belly pain, or eye redness.
Causes and who gets it
Relapsing fever is caused by Borrelia bacteria spread through bites from soft ticks or body lice. Soft ticks often live in rodent nests inside rustic cabins, so campers in rural areas can be exposed at night. The lice-borne form is more common in crowded conditions where people cannot wash clothing regularly.
How doctors diagnose it
Doctors suspect relapsing fever when someone has repeating fever cycles along with possible tick or lice exposure. They confirm it with a blood test that looks for the spiral-shaped bacteria, which are easiest to find during a fever.
Treatment
Relapsing fever is treated with antibiotics, such as doxycycline, taken by mouth for about a week. Most people improve quickly, though some get a brief reaction with fever and chills after the first dose. Fluids, rest, and fever-reducing medicine like acetaminophen help with symptoms.
When to see a doctor
See a doctor if you have a fever that keeps coming back, especially after camping, sleeping in a rustic cabin, or having lice. Get care quickly if the fever is very high or comes with confusion, severe headache, trouble breathing, or dehydration.
How a direct primary care or concierge doctor fits in
A direct primary care doctor, who charges a flat monthly fee instead of billing insurance, can often handle this problem directly, as can a concierge doctor, who usually charges more and often works alongside insurance. These doctors offer longer appointments and easier access, so they can take a careful history, order blood tests, and prescribe antibiotics. If the fever does not improve or the patient is pregnant, they will refer to an infectious disease specialist.
Common questions
Can relapsing fever go away without treatment?
The fever cycles can sometimes stop on their own, but the bacteria may remain in the body and cause serious problems. Doctors recommend antibiotics for anyone diagnosed.
Is relapsing fever the same as Lyme disease?
No. Both are caused by Borrelia bacteria and spread by ticks, but they are different illnesses. Relapsing fever comes from soft ticks, while Lyme disease comes from hard ticks.
How can I prevent relapsing fever?
Avoid sleeping in buildings where rodents have nested, and seal gaps where rodents can enter cabins. Use insect repellent and treat bedding in rustic housing. There is no vaccine.
Can relapsing fever spread from person to person?
The tick-borne form does not spread directly between people. The lice-borne form can spread when lice move from an infected person to someone else. Good hygiene and clean clothing help prevent lice.
Sources
- NIH Genetic and Rare Diseases Information Center - Relapsing fever
- MedlinePlus - Tick Bites
- Centers for Disease Control and Prevention - About Tick and Louse-borne Relapsing Fevers | Tick and Louse-borne Relapsing Fevers
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
