Tick-borne encephalitis in Bulgaria, 2009 to 2012 Mohareb, E and Christova, I and Soliman, A and Younan, R and Kantardjiev, T, Eurosurveillance, 18, 20635 (2013), https://doi.org/10.2807/1560-7917.ES2013.18.46.20635