B-FREE Chronic Babesiosis Study

Inclusion Criteria:

* Male or female, aged ≥ 18 years
* Severe disabling fatigue
* Have at least one common symptom of babesiosis
* Have laboratory evidence of exposure to babesia in the last 12 months
* Able and willing to give written informed consent
* Able and willing to perform all study assessments
* If female negative urine pregnancy test and
* If female agree to use an acceptable method of birth control

Exclusion Criteria:

* Glucose-6-phosphate-dehydrogenase (G6PD) deficiency
* Breastfeeding
* Unmanaged Psychotic disorder
* Known hypersensitivity reaction to tafenoquine or other 8-aminoquinolines
* Current or planned treatment with quinine
* Uncontrolled cardiopulmonary or endocrine disorders
* Taking OCT2/MATE substrates without appropriate medical oversight
* Medical history of chronic, active viral diseases including HIV/AIDS, hepatitis B, and hepatitis C
* Have a risk factors for relapsing babesiosis
* Anorexia
* Any concomitant significant illness unrelated to babesiosis
* The patient is unable to tolerate medication by the oral route
* The patient has previously taken tafenoquine
* Hemoglobin at baseline is ≤ 8 g/dL