Comparative study of molecular and non-molecular tools for peste des petits ruminants virus detection in West African Dwarf goats

Abstract

Abstract Peste des petits ruminants (PPR) causes severe economic losses to many countries of the world where the disease is endemic. It has been targeted for global eradication by 2030 following the successful eradication of rinderpest in 2011. The proposed eradication program would benefit from efficient and relatively reliable diagnostic tools for early PPR virus (PPRV) detection. A total of 33 eight to 12 months old West African Dwarf (WAD) goats were used. Nineteen goats infected by comingling with two PPR virus positive animals formed the infected group (PPRV-infected goats) while 14 non-infected goats formed the control group (CTG). The suitability of a molecular method (Hydroxyl naphthol blue (HNB) staining of reverse transcription loop mediated isothermal amplification (RT-LAMP)) and a non-molecular tool (haemagluttination assay (HA)) were compared for their sensitivity to detect the PPRV in PPRV-infected goats and non-infected CTG. PPR disease severity in WAD goats at different days post infection (dpi) was evaluated by clinical scoring and haemagluttination titre (HAT). HNB staining RT-LAMP reaction and HA showed sensitivities of 100% and 73.68%, respectively, for PPRV detection. Expression of PPR clinical signs began from 3 dpi, attained peak at 5 dpi, thereafter showed irregular patterns till 24 dpi. Evaluation of HAT in PPRV-infected goats at 12 dpi ranged from 2 to 64 haemagluttination units (HAU), while CTG goats had 0 HAU. In conclusion, HNB staining RT-LAMP assay demonstrated reasonable potential for accurate diagnoses of PPRV and as an important diagnostic tool in areas with poor electricity supply and less sophisticated laboratory equipment.