Transcription‐mediated amplification blood donation screening for Babesia

Abstract

BACKGROUND Transfusion‐transmitted Babesia microti is well recognized in the Northeast and upper Midwestern United States. Blood donation screening in Babesia‐endemic states has occurred under investigational protocols prior to US Food and Drug Administration–licensed test availability. Here, we provide a prospective screening summary of nucleic acid testing (NAT) as part of a multicenter Babesia pivotal trial followed by extended investigational use. METHODS From June 2017 to February 2018, 176,928 donation samples were tested with Procleix Babesia Assay (Grifols Diagnostic Solutions), a blood screening NAT for Babesia species ribosomal RNA detection using whole blood samples. During the pivotal trial, donations were collected in 11 endemic states plus Washington, DC, and Florida (nonendemic). Whole blood lysate samples were either tested in pools of 16 or individually. Reactive samples were confirmed by Babesia microti antibody and polymerase chain reaction (PCR) testing. If unconfirmed, further testing used a second PCR assay capable of detecting multiple Babesia species. Follow‐up samples were also tested. Extended investigational testing followed pivotal trial completion. RESULTS The pivotal trial identified 61 confirmed positives (176,608 donations): 35 (57%) PCR positive, 59 (97%) antibody positive, and two (3%) NAT positive/antibody negative, for a total yield of one positive per 2895 donations, including one Florida resident; others were from seven endemic states. During extended investigational testing of 496,270 donations in endemic states through January 2019, 211 (1:2351) repeat reactive donations were identified. CONCLUSIONS Babesia was detected in donors from multiple US states, including one previously not associated with positive blood donors. This study supports the use of the Procleix Babesia Assay using individual testing or pools of up to 16.

Preventing Transfusion-Transmitted Babesiosis

“…In addition, the incubation period for development of symptoms after transfusion is as long as six months [ 6 ]. Furthermore, donor surveillance studies and prospective screening have also identified parasitemic donations (i.e., positive nucleic acid test) throughout the year, although positive donations still tend to occur from June to October [ 33 ].…”

Detection of Anaplasma phagocytophilum, Babesia odocoilei, Babesia sp., Borrelia burgdorferi Sensu Lato, and Hepatozoon canis in Ixodes scapularis Ticks Collected in Eastern Canada

“…Not only are babesial piroplasmids transmitted by ticks, they are transmitted by blood transfusion [53], organ transplantation [54], and maternal-fetal transmission [55][56][57][58]. Similarly, Lyme disease spirochetes can be transmitted by maternal-fetal transmission [59][60][61][62][63].…”

Babesia microti: Pathogen Genomics, Genetic Variability, Immunodominant Antigens, and Pathogenesis

“…Limited epidemiological surveys in Babesia-endemic states using laboratory-based nucleic-acid-based tests (NAT) and antibody testing have provided important information about the percentage of asymptomatic infected donors, the relationship between seropositivity and parasitemia, and the seasonality of transmission in endemic areas (Leiby et al, 2005(Leiby et al, , 2014Johnson et al, 2009). In more recent years, results from prospective studies in large cohorts of blood donors conducted under the Investigational New Drug protocols have shed light on the prevalence of B. microti infections in asymptomatic healthy adults in endemic areas and non-endemic states (Levin et al, 2016;Moritz et al, 2016;Tonnetti et al, 2020). Results showed one confirmed infected sample per 1331 donations in endemic states (67 positives/89,153 donations) (Moritz et al, 2014) and one confirmed positive per 2351 donations (211 positives/496,270 donations) (Tonnetti et al, 2020) in endemic states plus Florida using investigational NAT assays.…”

“…In more recent years, results from prospective studies in large cohorts of blood donors conducted under the Investigational New Drug protocols have shed light on the prevalence of B. microti infections in asymptomatic healthy adults in endemic areas and non-endemic states (Levin et al, 2016;Moritz et al, 2016;Tonnetti et al, 2020). Results showed one confirmed infected sample per 1331 donations in endemic states (67 positives/89,153 donations) (Moritz et al, 2014) and one confirmed positive per 2351 donations (211 positives/496,270 donations) (Tonnetti et al, 2020) in endemic states plus Florida using investigational NAT assays. Cumulative results from the surveillance programs (Herwaldt et al, 2011;Linden et al, 2018;Gray and Herwaldt, 2019) and donor testing studies (Johnson et al, 2009;Moritz et al, 2016) have revealed that while tickborne infections are seasonal, transfusion transmitted cases occur year-round, although they too peak during the tick-transmission season.…”