Persistent human babesiosis with low-grade parasitemia, challenges for clinical diagnosis and management

Human babesiosis, caused by several Babesia parasites and transmitted by tick bites and other blood-associated containments, has emerged as a major public health threat around the world. In the absence of readily discernible clinical manifestations, the diagnosis of human babesiosis has been contingent upon the identification of Babesia parasites through the utilization of detection arrays. Nevertheless, cases of persistent and relapsing babesiosis with low-grade parasitemia have been sporadically observed in patients with and without immunosuppression, prompting a challenge to the reliability of routine clinical laboratory tests and efficient anti-babesial therapy. In such instances, it is essential to implement repeated and prolonged monitoring until complete eradication of the parasites is achieved. This review presents an overview of the epidemiology of persistent and relapsing human babesiosis, current diagnostic techniques, the mechanism of persistent relapse and practical clinical management strategies. In order to respond effectively to the challenge of low-grade parasitemia infection in the aforementioned patients, it is essential to prioritize the development and validation of rapid, sensitive, and cost-effective point-of-care diagnostic techniques, as well as the development of novel pharmaceutical agents and their combinations.