New test for blood donors after international travel
12:30am Wednesday 28th March 2012 in News
A test for West Nile Virus (WNV) will be introduced for certain blood donors in England and North Wales, from May 1.
Blood from donors who have returned from countries where WNV is prevalent will be tested, meaning immediate donation will be allowed by people who may have visited an affected country.
Previously donors had to wait 28 days before donating, after returning from a country where WNV is endemic.
These include the USA, Canada, Italy, mainland Greece, Romania, Former Yugoslav Republic of Macedonia, Turkey, Albania, Israel and some areas of Russia.
Welcoming the change, Dr Lorna Williamson, Medical & Research Director for NHS Blood and Transplant said: "Ensuring the safety and sufficiency of the blood supply is a priority.
"Testing for WNV ensures the risk of the infection is removed, while helping to keep blood stocks more stable over the summer months.
"This is particularly important this year, with the extra Bank Holiday and Olympics, so we would urge donors to try and attend when invited."
Tests will be carried out on donations during the risk period, May 1 and November 30 when less than four weeks have passed since the donor’s return from an area where WNV is endemic.
West Nile Virus is spread by mosquitoes and was first recognised in 1937 in Uganda.
It emerged in New York in 1999 and in 2002, transfusion transmitted cases were reported in the USA.
By 2003, 46 US states were reporting human cases and the UK blood services began to defer donors returning from North America.
During the intervening years, WNV has been reported in a growing number of countries in Europe. Currently there is no vaccine and the best way to prevent infection is to avoid being bitten by mosquitoes.
For most people, WNV infection will produce no symptoms or result in mild flu-like symptoms.
However for a small number, infection could result in a more severe form of the disease which could result in death for those with a poor immune system, for example small babies or patients who have received stem cell transplants.
Donor acceptance guidelines ensure not only that donated blood is safe for patients but also that donating blood is safe for donors. They are regularly reviewed and revised when necessary.
Other recent changes include an amendment to the donor guidelines to reduce the risk of faints, which are significantly more common in younger women.
Research has shown that a blood loss of 15 per cent of estimated blood volume can result in shock.
Using a donor’s weight and height to estimate blood volume and only allow donation from those not thought to be at risk, will help to remove this risk.