Detection of African horse sickness virus by reverse transcription-PCR.

This research article presents a new, rapid method for detecting the African horse sickness virus in infected horses by using reverse transcription PCR (RT-PCR) and single primer pair amplification.

Methodology

• The approach employed to detect the African horse sickness virus (AHSV) was Reverse Transcription-Polymerase Chain Reaction (RT-PCR).
• A unique primer pair was discovered that amplified a 423 base pair fragment of the S8 gene. This gene is responsible for encoding the NS2 protein of AHSV.
• The same primer pair could amplify this fragment from all nine serotypes of AHSV, indicating the wide applicability of the method.

Detection Sensitivity and Range

• The team was able to identify between 10^1 and 10^2 copies of AHSV genomic double-stranded RNA using RT-PCR, followed by agarose gel electrophoresis and ethidium bromide staining.
• This method revealed a high sensitivity considering the small amounts of AHSV genomic RNA that could be detected.

Application of the Method

• The research team applied RT-PCR to blood samples from AHSV-infected horses which resulted in earlier detection of viremia than through the standard method of virus isolation.
• Interestingly, they also found viremia through RT-PCR in blood samples from horses infected with an avirulent isolate of AHSV, which came out negative using the virus isolation method.
• The study also extended the implementation of RT-PCR to organ samples, discovering AHSV in spleen and lung samples from horses that had died from AHSV infection.

Conclusion

• The outcomes of this research show that RT-PCR is an effective, early, and sensitive tool for identifying horses infected with AHSV.
• The use of RT-PCR can greatly speed up the process and improve the accuracy of diagnosing AHSV, thus helping in the quick treatment and control of the disease in horses.