Climate change threats to the blood supply

Abstract

Background Current microbial blood safety practice of the blood supply is based on calculated risks posed by known bloodborne pathogens (e.g. HIV or Hep B) with subsequent enforcement of protective measures, such as donor and donation screening to identify and defer potential high risk donors. The convergence of infectious disease drivers such as climate change and international air travel has created conditions amenable to the donor related transmission of emerging infectious diseases (EID) through blood transfusion. Aims We evaluated the risk to the blood supply from global environmental change in Europe with the aim to identify and prioritize EIDs threats. Methods Two official government assessments were conducted to prioritize EID according to risk for the blood supply from climate change. The first assessment ranked EIDs threats from climate change; the second from their impact to the safety of substances of human origin in the EU. These two rankings were merged and is listed below. Results The overall priority rank was: 1) West Nile Fever; 2) Dengue; 3) Leishmaniasis; 4) Chikungunya fever; 5) Malaria; 6) Tick-Borne Encephalitis; 7) Borreliosis; 8) Crimean-Congo hemorrhagic fever. The climate change threat from these EIDs was mapped out for each EU country and weighted against evidence from the literature. This ranking illustrates that traditional screening tests of the blood supply run up against cost-effectiveness and feasibility limits; moreover, new pathogens can easily evade detection until sensitive tests have been developed. Thus, contamination of the blood supply with EIDs is a serious patient safety concern. Conclusions This predicament calls for alternative strategies such as pathogen reduction technology. It can be applied to most known and unknown agents and in combination with donor and donation screening this strategy might ultimately be the way forward to assure the safety, adequacy, and affordability of the blood supply.