Use of a NAT-based assay to improve the surveillance system and prevent transfusion-transmitted malaria in blood banks

Abstract

Background Malaria can be transmitted by blood transfusion through donations collected from asymptomatic donors. Transfusion-transmitted malaria (TTM) poses a great risk to blood services worldwide. A good screening tool for Plasmodium spp. detection in blood banks must have a high sensitivity for prevention of TTM. However, in Brazilian blood banks, screening for malaria still relies on microscopy. Methods In Brazil, screening for human immunodeficiency virus type 1 (HIV), RNA/DNA for hepatitis C (HCV) and hepatitis B (HBV) viruses is mandatory for every blood donation and uses nucleic acid amplification testing (NAT). The aim of this study was to evaluate the inclusion of an assay for malaria to identify Plasmodium sp. from total nucleic acid (TNA; DNA/RNA) by targeting the 18S rRNA gene of the parasite. Results Considering the limitations of microscopy and the wide availability of the Brazilian NAT platform in the screening of blood units for HIV, HCV, and HBV, a molecular diagnostic tool was validated for detection of Plasmodium sp. in blood banks; a pilot study showed that using this novel NAT assay could reduce the risk of TTM. Conclusion The prototype HIV/HCV/HBV/malaria NAT assay was effective in detecting infected candidate donors and has good prospects to be applied in routine screening for preventing TTM.

Current Situation of Transfusion-Transmitted Malaria in China

“…That said, there has been little research on its practical application for malaria screening in blood banks. A prototype HIV/HCV/HBV/malaria NAT assay was developed and validated in Brazil and has been shown to be a promising alternative for screening for malaria in blood banks in both endemic and nonendemic regions [ 36 ]. Despite this, the cost and infrastructure demands of this method still prevent its effective application in routine screening.…”

Transfusion-Transmitted Malaria and Mitigation Strategies in Nonendemic Regions

“…A research PCR for 18S rRNA gene was reported to detect Plasmodium DNA in samples from 19/101 (18.81%) asymptomatic adults in Ghana who tested negative by microscopy [73]. The prototype of an automated multiplex NAT method was recently described, using the 18S rRNA gene target [74]. In a pilot study of 4,745 blood donations, three donors infected with P. vivax were identified with parasitemia concentrations ranging from 13 to 1,410 copies/µL.…”

Malaria

“…Eine Arbeit aus Brasilien beschreibt hingegen in der Spendetestung für den PCR-basierten mitochondrialen DNA Nachweis von P. vivax sogar eine Sensitivität von 6 × 10 -6 Parasiten/µl Blut [70]. In diesem Zusammenhang wurde kürzlich aus Brasilien der Prototyp eines Multiplex-NAT Verfahrens beschrieben, das unter anderem auch Plasmodien auf Genusebene anhand der 18S rRNA detektiert [95]. In einer Pilotstudie wurden in 4745 Blutspenden drei mit P. vivax infizierte Spender identifiziert.…”