West Nile Virus - Irish Blood Transfusion Service

West Nile Virus

What is West Nile Virus?

West Nile Virus(WNV) is an infection in birds, which can occasionally be transmitted to humans via the bites of certain mosquitoes. Normally the infected person will not show signs of the illness. Sometimes the individual may have mild flu-like symptoms and in a few cases, it can develop into a more severe illness.

The virus is present in the blood of an infected person. If this blood is transfused to a patient, they may go on to develop West Nile Virus infection. We therefore ask you not to donate for 28 days after leaving an area that has a risk of WNV.

WNV is transmitted by mosquitoes and the areas at risk change throughout the year according to the seasons. The IBTS tests blood donations for WNV during the most at risk seasons each year. While we are testing, the deferral period of 28 days after leaving an at risk area does not apply.  

If you have been unwell during your visit abroad (or since your return from abroad) please phone us at 1850 731137 so that we might advise you on your eligibility to donate.

Number of Cases

West Nile Virus Infection is widespread in North America and throughout Europe.  In the last few years the number of areas affected in Europe has increased. If you have been unwell while abroad or since returning we recommend that you visit your GP for advice.  If you have been diagnosed as having WNV Infection or have symptoms of WNV Infection, we ask that you do not donate for 6 months after complete recovery.  This is a precaution to make sure that the virus is not still in your blood even though you feel well.      

Sometimes cases of WNV infection are reported in areas where they have not occurred before. As the areas at   risk of WNV change over time and with the seasons, we advise that you ask us for further information if you have been abroad recently by contacting us at 1850 731137 or send us your query.