Transfusion-Transmitted Malaria and Mitigation Strategies in Nonendemic Regions

Abstract

<b><i>Background:</i></b> Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the genus <i>Plasmodium</i>. These parasites can be transmitted by blood transfusion especially through Red Cell Blood Concentrates collected from asymptomatic and parasitemic donors. As migration of populations from endemic areas to Europe and overseas recreational travel to endemic regions increase, there is growing risk of transfusion-transmitted malaria (TTM) in nonendemic regions of the world. The present work provides an overview of the mitigation strategies in nonendemic countries and their effectiveness and discusses possible approaches to evolve the strategies in order to maintain both a safe and adequate blood supply. <b><i>Summary:</i></b> The historical and current situation of malaria and TTM in Europe and on the North American continent are described. The infectivity of <i>Plasmodium</i> in blood components and the consequences of TTM are presented, along with the regulations and guidelines for TTM mitigation in Europe, USA, and Canada. The regulations/guidelines currently in place in Europe allow a certain amount of leeway for local policies. A questionnaire was used to survey European countries regarding their current strategies and recent TTM cases. From the questionnaire and published cases, approximately 20 cases of TTM were identified in the past 20 years in the USA and Europe. The vast majority of implicated donors have been former residents of malaria-endemic areas, particularly former residents of hyperendemic areas in Africa. The most recent TTM cases are discussed in detail to provide insight into the gaps in current strategies. The utility and uncertainties of pathogen reduction and serological and molecular testing methods are discussed. <b><i>Key Messages:</i></b> Overall, the risk of transfusion-associated malaria in nonendemic countries is considered to be low and very few TTM cases occurred in these regions in the last 20 years. The questionnaire-based strategy with questions about risk in relation to malaria exposure with or without selective testing based on questioning seems to be relatively effective, although rare and sometimes fatal transmissions still occur. An outstanding question is whether in the future molecular methods may further improve the safety of blood products and help constrain the loss of donors.

Skrining parasit malaria pada kantong darah di Unit Transfusi Darah Palang Merah Indonesia (PMI) Cabang Kota Banda Aceh

“…Negara non-endemik, identifikasi pendonor yang berisiko terinfeksi Plasmodium telah menjadi isu penting terutama dengan peningkatan perjalanan orang dan fenomena migrasi, yang mengarah pada implementasi kebijakan keamanan darah (Niederhauser & Galel, 2022). Transfusi dengan darah yang terinfeksi Plasmodium merupakan risiko penularan malaria, suatu peristiwa yang jarang terjadi namun berdampak parah (Mangano et al, 2019).…”

Detection of Plasmodium spp. in asymptomatic blood donors by the new Brazilian NAT PLUS HIV/HBV/HCV/Malaria Bio‐Manguinhos kit

“…These individuals have the potential to act as reservoirs, which could lead to disease transmission through the bites of viable vectors or eventually blood transfusion. 7,8 Given these potential risks, strategies to advance blood donor screening must be employed since the risk of TTM can be increased even in nonendemic areas due to the increase in migration. 8 The current Brazilian Guidelines for Blood Establishments do not mandate malaria testing in nonendemic areas unless the blood center chooses to accept donors who have either recently moved from or originated in endemic areas within a window of 30 days to less than 12 months prior to donation.…”

Emerging Pathogens: Novel and Well-Known Infectious Threats in Transfusion Medicine

“…The current issue of Transfusion Medicine and Hemotherapy is dedicated to novel aspects of emerging infectious threats in transfusion medicine. The articles in this issue focus on Plasmodium [ 1 , 2 ] and viral threats like West Nile virus (WNV) and SARS-CoV-2 [ 3 , 4 ], reflecting current national test strategies and requirements.…”

“…An enhanced spread of infectious diseases associated with travel and migrations will include impacts related to blood transfusion, hence the traditional assumption of minimal risk associated with blood safety is being challenged by climate change, migration, and travel activities [ 11 ]. Niederhauser and Galel [ 1 ] review the status of TT malaria (TTM) and mitigation strategies in nonendemic regions. Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the genus Plasmodium .…”

“…Although malaria does not threaten to become an autochthonous infection in central Europe at least in the near future [ 12 ], the parasites can also be transmitted by blood transfusion, especially through red cell blood concentrates collected from asymptomatic and parasitemic donors from endemic countries. Overall, the risk of transfusion-associated malaria in nonendemic countries is considered to be low, and very few TTM cases occurred in these regions in the last 2 decades [ 1 ]. However, as more donors who originate from endemic countries are expected (and wanted) to introduce themselves as blood donors, sufficient strategies for the prevention of TTM are needed.…”