Babesia Incubation Period: A 10-Week Delayed Case
The babesia incubation period can be much longer than expected—as this unusual case demonstrates. A 19-year-old man developed symptoms 10 weeks after traveling to New York, illustrating why Babesia can be missed when physicians focus only on recent tick exposure.
The case was published in Cureus by Patel and colleagues.
The Case: A 10-Week Babesia Incubation Period
Ten weeks after traveling to New York, the patient was diagnosed with Babesia. Initially, he presented with a 4-day history of fever, generalized weakness, and flu-like symptoms.
His temperature reached 104.8°F. His hemoglobin dropped rapidly from 9.3 g/dL to 6.7 g/dL within 5 hours. He was diagnosed with hemolysis and required transfusion with two units of packed red blood cells.
A peripheral blood smear revealed a Maltese cross pattern—an important diagnostic clue for Babesia.
Why This Patient Was at Higher Risk
Babesia infections are more likely to cause severe disease in individuals without a spleen.
This patient had undergone splenectomy for hereditary spherocytosis when he was 3 years old, placing him at increased risk for severe babesiosis.
Babesia infections are most commonly reported in the Northeastern United States. This patient had traveled to New York—an endemic area—but presented with illness in Florida, where the infection is less common.
This geographic mismatch may have contributed to the diagnostic delay.
Diagnosis and Treatment
Early in the illness, Babesia may be identified with a thick blood smear under the microscope. Later in the disease course, PCR or antibody testing may confirm infection.
The patient was initially prescribed quinine but discontinued the medication due to headache, tinnitus, and blurred vision.
He was successfully treated with a combination of atovaquone, clindamycin, and azithromycin.
Other Cases of Extended Babesia Incubation
Delayed presentations have also been described in cases of congenital babesiosis.
In one report, two mothers treated for Lyme disease during pregnancy later delivered infants who appeared healthy at birth. Weeks after discharge from the hospital, both babies developed illness due to Babesia.
This pattern of congenital babesiosis with delayed onset supports the possibility that the babesia incubation period may extend well beyond what clinicians expect.
Why the Babesia Incubation Period Matters
This case illustrates several important clinical points:
- The babesia incubation period may extend to 10 weeks or longer
- Babesia can present outside endemic regions if patients have traveled
- Patients without a spleen are at increased risk for severe infection
- A detailed travel history is essential for diagnosis
When symptoms develop weeks after exposure, Lyme disease treatment may already have been completed—allowing babesiosis to remain undiagnosed.
Frequently Asked Questions
How long is the babesia incubation period?
The babesia incubation period typically ranges from 1–4 weeks but may extend to 10 weeks or longer, as demonstrated in this case.
Why was this patient diagnosed in Florida?
The patient had traveled to New York—an endemic area—10 weeks before symptoms developed. Babesia is less common in Florida, which may have contributed to the delay in diagnosis.
Why were this patient’s symptoms severe?
The patient had previously undergone splenectomy. Without a spleen, the body cannot effectively remove infected red blood cells, increasing the risk of severe disease.
What is a Maltese cross?
A Maltese cross is a distinctive four-cell parasite formation visible on blood smear that strongly suggests Babesia infection.
Can babies develop Babesia after birth?
Yes. In congenital cases, infants may appear healthy at birth but develop symptoms weeks later.
References
- Patel JK, Tirumalasetty K, Zeidan B Jr, Desai P, Frunzi J. A Case Report of Babesiosis Seen Outside of its Endemic Area and Incubation Period. Cureus. 2020;12(12):e11926.
- Saetre K, Godhwani N, Maria M, et al. Congenital Babesiosis After Maternal Infection With Borrelia burgdorferi and Babesia microti. J Pediatric Infect Dis Soc. 2018;7(1):e1-e5.
When I was 59, I was diagnosed with only Babesia after a screening for lyme and co-infections. I was treated for Lyme with doxi at least twice prior, my tests show I had Lyme in the past. After initial treatment of Atovaquone and azithromycin I was told I was cured without ever getting a second test taken. I did not have any have of the classic fevers with babesia – but I had night sweats and air hunger for many years. I was taking cingular for the air hunger for years before the diagnosis. I now am working with a herbal acupuncturist for chronic Lyme and I am off the cingular.
My main symptoms are fatigue, I have a window of hours when I’m feeling ok, then wham a blanket of fatigue covers me and I have get horizontal. I do have body aches and pain, but that is manageable. I never know when the blanket will hit. With the treatment, my window of feeling ok is increasing.
Question: can babesia hang around and flare up like Lyme? If I am not careful in the heat & humidity my air hunger returns. The night sweats have never gone away, but during a flare, the sweat smells sickly. Sometimes I have to change my clothes 5 times a night. This can happen maybe 2-4 times a year.
Thank you
I have patients in my practice whose long term illness does well with empiric treatment for Babesia. Some of them have sweats and air hunger.