Fatal Babesiosis: When a Tick-Borne Infection Turns Deadly
Fatal babesiosis is uncommon but well documented. While many cases occur in older or immunocompromised patients, severe infection can occasionally develop in individuals without classic risk factors. In this case report, a man without asplenia or advanced age died from babesiosis despite receiving appropriate treatment.
The man presented to the emergency department with fatigue, generalized weakness, and intermittent subjective fevers that had worsened over a two-week period.
He also reported headaches, vision changes, nausea, vomiting, and diarrhea. His medical history included type 2 diabetes and intermittent asthma.
“He denied any known recent tick or animal exposures, any recent travel, or previous blood transfusions,” the authors write.
On arrival to the emergency department, the patient was tachycardic, afebrile, and normotensive. A blood smear revealed small ring-form parasites with approximately 25% of red blood cells infected, findings consistent with babesiosis.
Fatal Babesiosis: An Emerging Tick-Borne Threat
Human babesiosis is an emerging tick-borne infection, with rising case numbers reported in the Northeastern United States over the past several decades.
The patient was admitted to the intensive care unit and began treatment with azithromycin and atovaquone, along with doxycycline for possible tick-borne co-infections such as Lyme disease.
Despite treatment, the patient’s condition deteriorated the following day. He required endotracheal intubation and mechanical ventilation. Several days later, he died.
“A few days following the patient’s death, babesia studies returned with PCR positive for B. microti and positive antibody findings (IgG 1:128 and IgM 1:160), confirming the diagnosis,” the authors wrote.
Why This Fatal Babesiosis Case Is Unusual
Most severe babesiosis cases occur in individuals with recognized risk factors such as asplenia, advanced age, or significant immune suppression. However, the authors emphasize that clinicians should remain vigilant even when these risk factors are absent.
“Clinicians should be aware that even in patients without the classic risk factors of asplenia, advanced age, and immunocompromised status, severe presentations of babesiosis can occur.”
Although the patient had type 2 diabetes, diabetes has not consistently been identified as a major risk factor for severe babesiosis.
This case illustrates that fatal babesiosis can occasionally occur unexpectedly and highlights the importance of early recognition and aggressive management.
Clinical Insight
References
- Selig T, Ilyas S, Theroux C, Lee J. Fatal Babesiosis in an Immunocompetent Patient. Rhode Island Medical Journal. 2022;105(6):20-23.
Related Reading
- Babesia and Lyme: What Patients Need to Know
- How Serious Is Babesia Infection?
- Babesia Symptoms Can Be Deadly: A Family’s Story
- Fatal Tick-Borne Disease Cases
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
Wonder if doctors ever considered the consequences of some of the medications used to treat the infection. I barely survived a round with Zithromax, I thought the issues I was having with the medication was a herxheimer- until I was totally unable to walk, breathe or talk. As it turned out, I have a heart condition called prolong QT syndrome and a result of the Zithromax, my heart went into ventricular fibrillation. It is amazing that I survived.
I was on the medications for a long time because entrenched infection is hard to get over. I knew other people on the medications as well and none of us had problems. Like everything else it depends on the person’s immune system, other infections and other health issues. Hope your better.
Wonderful, diabetes does not run in my family and I have been denying my doctors request to do an all day glucose lab testing for diabetes. And since, I contracted lyme/Babesoa..so many of the lab tests I do, do, I have to retake because they come out abnormal only to be normal when tested again or given a different test. A very disturbing article being Ive been treated for Babesia, Lyme etc etc. And so, this article states diabetes is a risk factor, if one has it or get its from Babesia? And, I still have vision problems.. very disturbing.
Alan MacDonald MD Comment – Grading the Severity of Babesios based on the percentage of parasitized Red blood cells
I have personally diagnosed over 100 cases of Babesiosis during my tenure as Pathologist at Southampton Hospital in Long Island New York in the period 1982-92. All cases were confirmed by the NY State Dept of Heatlh laborartory of Dr. Jorge L Benach after my initial “STAT” diagnosis of babesiosis from oil immersion microscopy ( minimum microscope time < 30 minutes per case) of thin smears of peripheral blood or from Bone marrow aspirates
My personal Grading System for Babesia infections in blood smear examinations is:
Grade 1 – Mild babesia infection – Less than 1% of RBc parasitized.
Grade 2 – Moderate babesia infection – up to 5% of RBC parasitized – Hospitalization indicated
Grade 3 – Severe and life threatening babesiosis – Any Asplenic patient, Any hyposplenic patient ( Lymphoma or Sickle cell dis)
and any patient with parasitemia greater than 10% of red blood cells.
These break points are based on data from Falciparum Malaria patients
My husband was diagnosed with Babesiosis after an initial diagnosis of pneumonia and 48 hours of ineffective treatment. I called 911 when his temp reached 102.6 and he had uncontrollable shakes, rapid HR and low oxygen saturation. His level was 9%. 5 days of Azithromycin and Atovaquone and he was sent home with another 5 days totaling 10 days of treatment. His anemia and other labs are all back to normal. But he’s wiped out.
Should he be followed by an infectious disease specialist? I’m worried about relapse. He is 71 and has type2 diabetes. We live in Maine. Thank God the ED doc knew to draw the tick panel!
Thank you!
I have had patients with Babesia in my practice who have benefited from more than 10 days of treatment.
Alan. Thanks for sharing. I am also concerned for my Babesia patients who ill despite the absence of Babesia on their blood smears.
I am glad to hear your cardiac problems from Zithromax were recognized by your doctor in time. I have had to couple another antibiotics with atovaquone for some of my patients if I am unable to prescribe Zithromax.
A man died in a southwest Virginia hospital when they failed to detect and treat his babesia case. He was a known lyme patient with years of treatment and a very knowledgeable wife. I don’t remember now if they tested him for babesia and it was negative and they didn’t follow up with a blood smear, or they just ignored it entirely. When you get into a hospital, they may not listen to even very well informed relatives.
Babesiosis and lyme,
bcommunications has been poor between the doctor who performed the test and me.
Maybe I can email the test result and we can have a consult. I don’t want to be over medicated
I have taken mepron and azithromycin and supplements.
Is the IGX FISH test an accurate reading for babesiosis? It presented as positive
Lyme immunoblot IgG serum showed as positive – bands 28 +, 31 ++, 41+, 45 IND
Thank you.
Also, if lyme bands 23 and 41 are indeterminate on the IGX borreliosis does it need to be treated?
I wish the tests were better. I have to rely on clinical judgment. I also work with other doctors at the same time to be sure I do not overlook another illness.
Apparently we don’t have Lyme disease or human babesiosis in Australia and yet we have ticks and vectors galore and people falling deathly ill post vector bites. This reports says first case of Australian Babesiosis, yet clinicians will still deny the fact it may be here. Our science is still catching up whilst some minds still remain closed to the possibility… https://www.mja.com.au/journal/2012/196/5/first-report-human-babesiosis-australia
When my wife experienced extreme fatigue, muscle and joint pain, headaches, neurological symptoms and others including a change in personality over a month after attachment of a female Lone Star tick for 6 to 10 hours, our PCP signed a blood test request for iGeneX. The results were positive for Bartonellosis, Ricketsii, a serum Titer of 320 for Babesia and indeterminate for Borrelia. Two one month courses of Doxy did not result in improvement. Finally an alternating 10 day protocol of two ABX and Quinine and Hydroxicloroquine for forty days resolved her symptoms.
I have found treatment for Babesia helpful. I typically use a combination of Malarone and Zithromax daily helpful rather then pulse therapy.
How do you treat a patient who develops hemolytic anemia on Tafenoquine and Dapsone separate combo therspies
Both can lead to anemia. I don’t prescribe Dapsone in part as it can lead to Methemoglobinemia patients may present with hypoxia, cyanosis, fatigue, dyspnea.