Babesia Positive Test But No Treatment: What This Case Reveals
Positive Babesia tests can create treatment uncertainty
Coinfections may complicate interpretation of symptoms
Delayed treatment decisions may carry risks
In his article, Wormser discusses the case of a 61-year-old woman who went untreated for a Babesia infection despite positive test results. The patient, who lives in Westchester, NY, a highly endemic area for Lyme disease, reportedly removed an unidentified tick from her left wrist at the end of March 2020, wrote Wormser.
This article discusses human Babesia infection rather than canine babesiosis.
A positive Babesia test without treatment creates difficult clinical questions. Does the infection require therapy? Could symptoms reflect Babesia alone, Lyme disease coinfection, or another tick-borne illness? This case highlights why positive test results do not always lead to straightforward decisions.
In endemic regions, clinicians often have to consider overlap between coinfections, diagnostic uncertainty, and persistent symptoms when evaluating positive results.
In June, she developed intermittent fevers, joint pain, anorexia, and fatigue and was evaluated at the Lyme Disease Diagnostic Center (LDDC) in New York State.
Babesia Symptoms Without an Erythema Migrans Rash
Unfortunately, the patient did not have an erythema migrans rash. As a result, she was not treated for a tick-borne infection.
On July 30, 2020, the woman tested positive by PCR for Babesia but was not treated.
Two weeks later, she had a positive Lyme disease EIA and one IgM Western blot band. But she was still not treated for either Lyme disease or Babesia.
On August 26, 2020, her Lyme disease tests were positive by the CDC’s two-tier diagnostic criteria. She had a positive EIA and positive IgM Western blot test. Still, she was not treated for either Lyme disease or Babesia.
On December 11, 2020, the woman’s PCR test for Babesia and IgM Western blot test for Lyme disease were negative. Her Lyme EIA remained positive.
An untreated Babesia infection may raise concerns regarding persistent symptoms, relapse risk, or missed coinfections, particularly in endemic regions.
Delayed recognition of tick-borne illnesses may complicate interpretation of symptoms, particularly when clinicians are balancing multiple diagnostic possibilities. Learn more about delayed Lyme disease diagnosis.
Babesia Coinfection Concerns
I. scapularis ticks recovered from the environment that are infected with B. microti may be coinfected with B. burgdorferi.
The woman never developed more than two IgM Western blot bands for Lyme disease. And she never exhibited an erythema migrans rash. If she had, it would have allowed Dr. Wormser to make the diagnosis of Lyme disease in a patient with Babesia.
As he states, “Diagnosing Lyme disease coinfection in patients with active babesiosis, as in patients with human granulocytic anaplasmosis, is more convincingly accomplished if objective clinical features of Lyme disease are present, such as an erythema migrans skin lesion.”
The relationship between Babesia and Lyme disease coinfection remains clinically important because overlapping symptoms may complicate treatment decisions. See more on Babesia and Lyme disease coinfection.
The woman’s fever resolved without treatment. But Dr. Wormser did not state whether the patient’s joint pains, anorexia, or fatigue had resolved. Neither did Dr. Wormser report whether there were any long-term sequelae from an untreated tick-borne illness.
Clinical Perspective
I would have been uncomfortable leaving the woman untreated, particularly since she had evidence of at least one tick-borne infection—Babesia.
The case raises difficult questions regarding how clinicians interpret positive Babesia PCR testing, persistent symptoms, and the possibility of coinfections in endemic regions.
Frequently Asked Questions
Does a positive Babesia PCR always require treatment?
Treatment decisions depend on symptoms, severity, immune status, and clinical context. Positive PCR testing generally suggests active infection, but interpretation should occur alongside the full clinical picture.
Can Babesia occur without Lyme disease?
Yes. Babesia can occur independently, although coinfection with Lyme disease is well recognized because both infections can be transmitted by the same tick species.
Can Babesia symptoms resolve without treatment?
Some patients may improve without treatment, but persistent symptoms, relapse, or ongoing infection remain concerns in selected cases.
What symptoms may occur with untreated Babesia infection?
Symptoms may include fatigue, fevers, sweats, joint pain, weakness, and exercise intolerance, although presentations vary widely between individuals.
Why does Babesia coinfection make diagnosis harder?
Coinfections may create overlapping symptom patterns, complicate testing interpretation, and make it harder to determine which infection is contributing most to symptoms.
Clinical Takeaway
Positive Babesia testing without treatment creates uncertainty for both clinicians and patients.
When positive Babesia tests occur in endemic regions, clinicians may need to carefully consider symptoms, coinfections, and the risks of delayed treatment decisions.
Related Articles
These articles explore Babesia symptoms, coinfections, persistent symptoms, and diagnostic challenges.
Lyme coinfections
Babesia symptoms
Post-treatment Lyme disease syndrome
Persistent Lyme disease
Babesia and Lyme disease coinfection
References
- Wormser GP. Documentation of a false positive Lyme disease serologic test in a patient with untreated Babesia microti infection carries implications for accurately determining the frequency of Lyme disease coinfections. Diagn Microbiol Infect Dis. 2021;101(1):115429.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
Thankfully my family doctor saw positive based on clinical observations, for Lyme and started me on antibiotics before the blood work came back proving that. It was caught and treated early, and I’ve been in remission since late 2012. Get rid of the bands, and the rash method and detect by CLINICALLY ASKING about and LISTENING TO PATIENTS symptons. Catch it sooner and treat aggressively!! I would not be alive today by the methods discussed in this article.
Unbelievable. Babesia (with Lyme, mycoplasma & toxoplasma) was responsible for my continued decline even though I received treatment for Lyme within 72 hours of exposure. It culminated in encephalitis, cognitive decline & constant fevers. Some symptoms resolved with IV antibiotics but UNTIL BABESIA WAS TREATED 2 YEARS LATER, I didn’t significantly improve. Now, 11 years later I still require oral Lyme & Babesia meds.
I have identical Lyme Carditis, I had a positive test but was never treated properly. I am left to die. 24 years of suffering and treated twice. Last time put on anibiotics I was resistant too. I had Babiesia diagnosis but I didn’t have Lyme Carditis symptoms until after improperly treated. Now I am dying. How do we get help.
I am sorry to hear you are still sick. Your story highlights how difficult it can be to be sure there is not an unresolved tick borne infection. I face this all the time in my practice. I also lean on other specialists to make sure there is not an underlying illness.
I was infected with Lyme Disease here in Asheville North Carolina a year ago. Fortunately, I had the rash behind my knee. I was treated and refused the short course of 10 days of doxycycline. I then saw an infectious disease doctor and was given a month of doxycycline. When I realized I had a nymph tick on the back of my knee I removed it and accidently dropped it on a patterned carpet. I vacuumed and remained concerned that it was in the apartment. My strictly indoor cat became ill and with great difficulty I got my vet to test him for Lyme. His test as she put it was only ‘mildly positive”. I then had difficulty getting him treated. I lived in Connecticut for years and Lyme was epidemic. I didn’t want to see him suffer from Lyme in his declining years. I don’t think people think of the fact that their dog can bring in an infected tick. The county health dept called to interview me regarding my case of Lyme. The nurse after hearing my story said “Oh yes, we had a diagnosis of Lyme and we treated the whole family and the dog.” I had Babiosis in Connecticut and was quite ill but didn’t have a diagnosis until a blood smear was taken through a Health Food Store. My question is does the Babesiosis remain in your body like Lyme?
I have patients who are failing other treatment until they add treatment for Babesia.
Why are doctors not treating this as a life threatening illness. I was just hospitalized for 5 days due to Babesia. I’ve never been so I’ll. For 3 days I was sleeping , fever, feeling paranoid, nightmares, nausea, headache, loss of balance, walking was affected, headache, loss of fine motor skills, my speech was declining like I was intoxicated. Finally went to the E.R. and had antibiotic I.V.and 5 other antibiotics. I am now having weekly blood tests and my platelets are being monitored ( total of 5 tests). If I had waited another couple days I would not be here. I thank my University of Penn professionals in Chester County, Pa.for getting me through this.
My mom has been extremely sick since 6 August. She developed the red rash on her arm the morning she went to urgent care (9 Aug) and was notified on 12 Aug that she tested positive for Lyme. The doctor, thankfully, was proactive and started her on doxycycline at the visit on the 9th. However, she continues to be very sick. After her second visit to the ER, we asked for testing for bartonella and Babesia, which both came back negative today. She has a headache (temples and eyes), extreme fatigue, body tremors, nausea, extreme loss of appetite with a weight loss of 16 pounds in the last 10 days, a chronic dry cough, shortness of breath upon exertion, gastrointestinal problems, short-term memory loss, and a CT shows she has some fluid around her heart. She sees her cardiologist tomorrow. My questions are, could she have those co-infections despite the tests being negative? Is it possibly the lyme bacteria has caused carditis which would be the reason for the cough? The doctor who tested for babesia and bartonella put her on a long and high tapered dose of prednisone (50 mg X 3 days, 40 mg X 3 days etc, down to 5 mg X 3 days) for the cough which seemed to make her get worse rather quickly. He agreed she could stop when it didn’t stop the cough after 4 days. We are at a loss and her PCM refuses to refer her anywhere for the lyme. We requested a referral to infectious disease at WVU Medical in Morgantown, WV but again, her said no. Any resources anyone can recommend so we can get mom the help she needs?
I have worked with patients who remain ill despite standard therapy for a tick borne illness. The tests for co-infections have not been as good as I would like. My patients also see other doctors to rule out other diseases including pulmonary and cardiac disease. Keep working on all fronts until she gets better.
I was exposed to mold at work for 8 years, diagnosed initially with Lyme through Igenex and clinically diagnosed with Babesia and Bartonella. Before being diagnosed with mold I had treated the lyme and co. For almost 2 years and many symptoms resolved but I had still persistent slurred speech and off balance and loss of fine motor skills that led to the testing for mold.
Although I treated with binders for over a year I didn’t have any resolution to these symptoms and then got Covid. All of my balance, slurred speech and motor skills have been exasperated and some new ones added. Could these symptoms be from babesia or from mold still although out of that exposure since I was diagnosed 12/4/20
I have had success with treating Lyme diseases and Babesia again. Others have reported success with mold treatment.