Duplex nested-PCR for detection of small ruminant lentiviruses

Area of Science:

• Veterinary Virology
• Molecular Diagnostics
• Infectious Disease Epidemiology

Background:

• Small ruminant lentiviruses (SRLV) exhibit high genetic variability, complicating molecular diagnostic primer design globally.
• Existing diagnostic methods like AGID have limitations in detecting SRLV infections accurately.

Purpose of the Study:

• To develop and validate a precise duplex nested-PCR protocol for SRLV diagnosis.
• To compare the efficacy of the novel duplex nested-PCR assay against traditional methods and single-target PCR assays.

Main Methods:

• Development and testing of a duplex nested-PCR protocol using control strains (CAEV Co, MVV 1514) and field isolates.
• Analysis of sheep and goat blood samples using AGID and nested PCR targeting pol, gag, and LTR gene regions.
• Evaluation of primer efficiency for different SRLV targets (pol, gag, LTR) in sheep and goats.

Main Results:

• Nested PCR demonstrated significantly higher virus detection capacity than AGID.
• LTR-PCR showed higher efficiency in detecting SRLV in sheep, while gag-PCR was effective for both sheep and goats.
• Pol-PCR was more sensitive in detecting SRLV in goats compared to sheep.
• The duplex nested PCR assay proved more efficient in detecting multiple pro-viral DNA sequences.

Conclusions:

• A successful duplex nested PCR assay for SRLV diagnosis has been established.
• This advanced molecular technique allows for more accurate and comprehensive detection of SRLV infections in small ruminants.
• The developed assay addresses the challenges posed by SRLV genetic diversity, improving diagnostic capabilities in different geographical regions.