- Nested cytochrome b polymerase chain reaction diagnostics underestimate mixed infections of avian blood haemosporidian parasites: microscopy is still essential. Valkiŭnas, G., Bensch, S., Iezhova, T.A., Krizanauskiené, A., Hellgren, O., Bolshakov, C.V. J. Parasitol. (2006)