Emergent Molecular Techniques Applied to the Detection of Porcine Viruses

SIMPLE SUMMARY: In this review, we examine the application of different molecular diagnostic techniques in the pig industry; qPCR, isothermal methods, and novel techniques such as CRISPR-Cas and microfluidics platforms are discussed in detail. The main viruses affecting the health of pigs were identified, including the African swine fever virus, porcine reproductive and respiratory syndrome virus, porcine epidemic diarrhea virus, and porcine circovirus. Furthermore, the main challenges for the implementation of large-scale molecular diagnostic tests in the swine industry are discussed, which include lower costs, ease of operation for any type of user, portability for use on farms, and rapid response times. ABSTRACT: Molecular diagnostic tests have evolved very rapidly in the field of human health, especially with the arrival of the recent pandemic caused by the SARS-CoV-2 virus. However, the animal sector is constantly neglected, even though accurate detection by molecular tools could represent economic advantages by preventing the spread of viruses. In this regard, the swine industry is of great interest. The main viruses that affect the swine industry are described in this review, including African swine fever virus (ASFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine epidemic diarrhea virus (PEDV), and porcine circovirus (PCV), which have been effectively detected by different molecular tools in recent times. Here, we describe the rationale of molecular techniques such as multiplex PCR, isothermal methods (LAMP, NASBA, RPA, and PSR) and novel methods such as CRISPR-Cas and microfluidics platforms. Successful molecular diagnostic developments are presented by highlighting their most important findings. Finally, we describe the barriers that hinder the large-scale development of affordable, accessible, rapid, and easy-to-use molecular diagnostic tests. The evolution of diagnostic techniques is critical to prevent the spread of viruses and the development of viral reservoirs in the swine industry that impact the possible development of future pandemics and the world economy.