Transfusion-transmitted babesiosis: is it time to screen the blood supply?

Abstract

Purpose of review To summarize the current status of blood screening to prevent transfusion-transmitted babesiosis. Recent findings Babesia microti has recently been determined to be the most common transfusion-transmitted pathogen in the United States. Patients who acquire transfusion transmitted babesiosis (TTB) often experience severe illness with an associated mortality rate of about 20%. Recent studies have demonstrated that laboratory screening using B. microti antibody and/or PCR assays can effectively identify infectious blood donors and that this approach may offer a cost effective means of intervention. Pathogen inactivation methods may offer an alternative solution. None of these methods has yet been licensed by FDA, however, and current efforts to prevent TTB rely on excluding blood donors who report having had babesiosis. Summary TTB imposes a significant health burden on the US population. Further research is needed to better inform decisions on optimal screening strategies and reentry criteria, but given the acute need and the currently available screening tools, initiation of blood donor screening to prevent TTB should be given high priority.

High-resolution melting PCR assay, applicable for diagnostics and screening studies, allowing detection and differentiation of several Babesia spp. infecting humans and animals

“…The clinical course of babesiosis in immunocompromised patients is often severe, and the mortality rate in such cases may reach 20% (Levin and Krause 2016 ). In contrast, in adult immunocompetent persons, who can be blood donors, the course of Babesia infection is asymptomatic.…”

“…Furthermore, Babesia infections pose a public health threat since the parasite can be transmitted not only through tick bites but also by transfusion of blood and blood products. However, there still are no standardized procedures of screening blood for Babesia even in such developed countries as the USA, where cases of babesiosis related to blood transfusion have been recorded (Bish et al 2015 ; Leiby 2006 ; Levin and Krause 2016 ).…”

“…In Asia, the public health risk associated with B. microti and B. venatorum infections has been recognized recently (Zhou et al 2013 , 2014 ). There are no official recommendations on laboratory diagnosis of Babesia infection both in the USA and in European countries (Hildebrandt et al 2013 ; Levin and Krause 2016 ). Definitive diagnosis in most cases still depends upon finding of parasites on blood smear examination.…”

Babesia microti: from Mice to Ticks to an Increasing Number of Highly Susceptible Humans

“…for screening blood donations, including immunologically based and nucleic acidbased platforms, have been evaluated in large clinical trials and exhibit high sensitivity and specificity (24). Serological prevalence in the donor population in regions in which the pathogen is endemic can be as high as 2%, with 12 to 20% of antibody-positive donors also being positive by PCR (25)(26)(27).…”

A new framework for the study of apicomplexan diversity across environments

“…In the case of the apicomplexans, the problems with the current state of our reference data are clear from comparisons of our manually curated reference database and tree with existing GenBank annotation. There are extensive mistakes in some human and animal parasites, like Theileria and Babesia [28] at the genus level (Sup Table 1…”