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PubMed This is a summary of 24 peer-reviewed journal articles Updated
Infectious Disease

Can I Get Babesiosis from a Blood Transfusion?

At a Glance

Yes, you can get babesiosis from a blood transfusion, though it is rare due to rigorous blood screening. Transfusion-Transmitted Babesiosis (TTB) symptoms like fever and dark urine can take 1 to 9 weeks, or up to 6 months, to appear after receiving blood from an asymptomatic donor.

In this answer

3 sections

01

The Incubation Period: Transfusion vs. Tick Bite

02

How Blood Banks Screen for Babesia

03

Who is Most at Risk?

Yes, it is possible to contract babesiosis from a blood transfusion, though it is considered a rare event today due to improved screening protocols. This is known as Transfusion-Transmitted Babesiosis (TTB) [1][2]. It happens when a person receives red blood cells donated by an individual who is infected with the Babesia parasite but is asymptomatic and unaware of their infection [3][4]. While the primary way people get babesiosis is through a tick bite, receiving infected blood products is a recognized alternative route of transmission [5][6].

The Incubation Period: Transfusion vs. Tick Bite

When someone gets babesiosis from a tick bite, the incubation period—the time between being exposed to the parasite and feeling sick—is typically between 1 and 6 weeks [7]. However, for transfusion-transmitted babesiosis, the incubation period is often longer and more variable. Symptoms typically appear anywhere from 1 to 9 weeks after the transfusion, and in some documented cases, the incubation period can take up to 6 months [8][9].

This longer window can sometimes lead to delays in diagnosis because doctors might not immediately connect a new onset of fever or fatigue to a blood transfusion received weeks or months earlier [10][1]. If you have passed the 6-month mark without developing symptoms, your risk of having contracted TTB from that transfusion is exceedingly low.

How Blood Banks Screen for Babesia

To protect the blood supply, blood banks use specific screening processes designed to catch the parasite before infected blood can be given to a patient. These strategies have substantially decreased the incidence of transfusion-transmitted babesiosis [11]:

  • Donor Questionnaires: Before any blood is drawn, donors are asked health history questions. Asking donors if they have ever had babesiosis is a critical first line of defense [12].
  • Nucleic Acid Testing (NAT): In the United States, the primary method used to screen donated blood for Babesia microti is NAT [13][11]. This highly sensitive test looks directly for the DNA of the Babesia parasite in the donor’s blood [14].
  • Antibody Testing: In addition to checking for DNA, some screening strategies may include testing for antibodies against the parasite, which indicate that a donor has been exposed to Babesia in the past [15][16].
  • Geographically Targeted Screening: Because babesiosis is much more common in certain parts of the United States (such as Massachusetts, New York, Connecticut, Minnesota, and Wisconsin), blood screening is often geographically targeted to these endemic areas [17][18].

While these screening measures are highly effective, rare breakthrough cases can still happen [17]. This is largely due to the limitations of geographically targeted testing—for example, a person who lives in a non-endemic area might travel to an endemic area, get bitten by a tick, and then donate blood in their home state where screening for Babesia isn’t routinely performed [14][11].

Who is Most at Risk?

Transfusion-transmitted babesiosis poses a serious health risk because the people who need blood transfusions are often already vulnerable [19]. Groups that are at a particularly high risk for severe complications from TTB include:

  • Older adults (the risk of severe complications increases for those over age 50) [20]
  • Newborns and premature infants (neonates) [19]
  • People without a spleen (asplenic), or whose spleen does not function properly (like those with sickle cell disease) [20]
  • Individuals with weakened immune systems (immunocompromised) [21][22]

The symptoms of TTB are the same as tick-borne babesiosis and can include high fever, severe fatigue, chills, and hemolytic anemia (the destruction of red blood cells), which may cause dark urine [7][23]. While severe, babesiosis is treatable when caught early [24]. If you have had a blood transfusion in the past 6 months and develop unexplained fever or flu-like symptoms, it is important to notify your healthcare provider and explicitly mention your recent transfusion.

Common questions in this guide

How long after a blood transfusion do babesiosis symptoms appear?
Symptoms of transfusion-transmitted babesiosis usually appear between 1 to 9 weeks after receiving contaminated blood. However, the incubation period can vary widely, and in some documented cases, it can take up to 6 months for symptoms to develop.
How do blood banks test for the Babesia parasite?
Blood banks use rigorous screening processes, including donor health questionnaires and Nucleic Acid Testing (NAT) to detect the parasite's DNA in the blood. Some regions also test for Babesia antibodies, particularly in areas where the infection is most common.
Who is at the highest risk for severe complications from transfusion-transmitted babesiosis?
Older adults over age 50, newborns, premature infants, and individuals with weakened immune systems are at the highest risk. People who do not have a spleen or whose spleen does not function properly also face a significantly increased risk of severe complications.
What symptoms should I watch for after a blood transfusion?
If you have had a blood transfusion in the past six months, watch for symptoms like high fever, severe fatigue, chills, and dark-colored urine. Dark urine can be a sign of hemolytic anemia, a condition where red blood cells are destroyed, and requires immediate medical attention.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Given my recent blood transfusion, if I develop an unexplained fever or fatigue in the next few months, will you specifically order a blood smear or PCR test to check for Babesia?
  2. 2.Considering my medical history and immune status, am I at an increased risk for complications if I were to contract a tick-borne infection from a transfusion?
  3. 3.Since we live in a non-endemic area, does our local blood bank import blood from endemic regions where Babesia is common, or do they screen all units regardless of origin?
  4. 4.What specific symptoms, like dark urine or extreme fatigue, should prompt me to go to the emergency room versus scheduling an outpatient appointment?

Questions For You

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Related questions

Can Babesiosis Pass to Your Baby During Pregnancy?Can Babesiosis Relapse After Treatment?Does Doxycycline Treat Babesiosis & Lyme Co-Infections?How Does Babesiosis Affect the Spleen and Cause Infarction?How Long Does Fatigue Last After Babesiosis Treatment?What Are the Different Species of Babesia?Side Effects of Atovaquone & Azithromycin for BabesiosisWhat Are the Symptoms of Lyme & Babesia Co-Infection?Why Does Babesiosis Cause Air Hunger & Shortness of Breath?What is a Maltese Cross on a Babesia Blood Smear?What Does Parasitemia Percentage Mean in Babesiosis?What is the Difference Between Babesiosis and Malaria?When Do Babesiosis Symptoms Start After a Tick Bite?Why Test LDH & Haptoglobin in a Babesiosis Infection?

References

References (24)
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    Transfusion transmitted babesiosis: A systematic review of reported cases.

    Tang TTM, Tran MH

    Transfusion and apheresis science : official journal of the World Apheresis Association : official journal of the European Society for Haemapheresis 2020; (59(5)):102843 doi:10.1016/j.transci.2020.102843.

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    Experimental transfusion-induced Babesia microti infection: dynamics of parasitemia and immune responses in a rhesus macaque model.

    Gumber S, Nascimento FS, Rogers KA, et al.

    Transfusion 2016; (56(6 Pt 2)):1508-19 doi:10.1111/trf.13521.

    PMID: 26892459
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    Transfusion-Transmitted Babesiosis.

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    Archives of pathology & laboratory medicine 2019; (143(1)):130-134 doi:10.5858/arpa.2017-0250-RS.

    PMID: 30376376
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    Preventing Transfusion-Transmitted Babesiosis.

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    Pathogens (Basel, Switzerland) 2021; (10(9)) doi:10.3390/pathogens10091176.

    PMID: 34578209
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    Prevalence of Babesia in Canadian blood donors: June-October 2018.

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    Transfusion-Transmitted Babesiosis During Total Hip Arthroplasty.

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    Cases of transfusion-transmitted babesiosis occurring in nonendemic areas: a diagnostic dilemma.

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This page explains the risks of transfusion-transmitted babesiosis for educational purposes only. Always contact your healthcare provider immediately if you develop a fever or unusual symptoms after receiving a blood transfusion.

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