Detection of peste des petits ruminants virus in formalin-fixed tissues

Peste des petits ruminants virus that causes a highly infectious and often fatal disease of sheep and goats is confirmed by various diagnostic techniques among them being isolation of the virus from cell culture systems, viral ribonucleic acid (RNA) detection by molecular assays, and viral antigen detection by immunocapture enzyme-linked immunosorbent assay (IC ELISA), immunohistochemistry (IHC), and AGAR gel test. Whereas most of the confirmatory diagnostic procedures require pathological samples to be stored frozen to preserve integrity of the peste des petits ruminants (PPR) virus RNA, samples for IHC tests are preserved in 10% formalin. In this study, nine formalin-fixed pathological samples from three goats suspected of PPR were processed for extraction of PPR viral RNA and analyzed for detection with real-time reverse transcription-polymerase chain reaction (qRT-PCR) assay. The results showed that five out of the nine tested samples returned positive for presences PPR viral genome. This study has established that field pathological samples of PPR-suspected cases, collected and stored in 10% formalin for up 2 years, could be used for PPR virus RNA extraction for disease virus confirmation.