Temporarily prohibiting blood donation after returning from many overseas countries is justified but costly to the blood supply, delegates attending HAA 2015 here in Adelaide have been told.
Ms Anna Coghlan, from the School of Medicine at The University of Queensland, calculated the likely risk that travellers would bring home not just their memories and souvenirs, but also an undiagnosed transmissible infection.
She analysed four areas affected by disease outbreaks: Fiji (dengue virus), Bali (dengue and chikungunya viruses), French Polynesia (Zika virus) and the Bueng Kan province of Thailand (chikungunya virus).
The model accounted for the number of travellers visiting these regions during an outbreak, the local prevalence of the infection and the tourists’ average length of stay.
“Using worst-case scenarios, we calculated that travel to Fiji during a severe dengue outbreak would have resulted in the highest risk, with up to 86 donors potentially infected each year,” she said.
“Travel to Bali during a peak period of dengue virus transmission would have led to up to 37 potentially infected donors per year, but a much lower risk – with less than 1 potentially infected donor per year – was estimated for the other areas we studied.”
The Australian Red Cross Blood Service collects about 1.3 million donations annually and imposes many country-specific deferrals on donation, most commonly because of the risk of endemic malaria. Australians make a total of about 9 million overseas trips a year.
“The aim is to maximise safety for donors and for the blood supply, but you can imagine the number of donations the blood service is missing out on,” she said.
“There are a number of potential problems. Deferral policies implemented by worldwide health policies may be left in place for years, and deferral often leads to a donor not returning to give blood again.”
“While the estimated risk of infection that we calculated was relatively low, this study demonstrates that current restrictions are justified in the interests of maintaining a very low-risk blood supply.”
Although it was premature to suggest any specific changes, refinements to the current system could potentially include a fixed-term deferral for any donor returning from any country overseas, aiming to simplify procedures in donation centres.
HAA 2015 is the Annual Scientific Meetings of the HAA (Haematology Society of Australia and New Zealand, the Australian & New Zealand Society of Blood Transfusion and the Australasian Society of Thrombosis and Haemostasis).