A new nested polymerase chain reaction method very efficient in detecting Plasmodium and Haemoproteus infections from avian blood.

Recently, several polymerase chain reaction (PCR)-based methods for detection and genetic identification of haemosporidian parasites in avian blood have been developed. Most of these have considerably higher sensitivity compared with traditional microscope-based examinations of blood smears. These new methods have already had a strong impact on several aspects of research on avian blood parasites. In this study, we present a new nested PCR approach, building on a previously published PCR method, which has significantly improved performance. We compare the new method with some existing assays and show, by sequence-based data, that the higher detection rate is mainly due to superior detection of Plasmodium spp. infections, which often are of low intensity and, therefore, hard to detect with other methods.