At present, RT-PCR-based techniques for the detection and typing (pathotyping and genotyping) of APMV-1
RNA in allantoic fluid of inoculated fowl eggs is becoming increasingly common in diagnostic laboratories.
However, the genetic variability of APMV-1 isolates should be considered carefully as potential cause for
false negative results of genetic-based laboratory tests. See Sections 1e; 1h and 1i of the present chapter