CRISPR-Based Point-of-Care Testing (POCT) Devices for Detection of Opportunistic Pathogens

Pathogens are microorganisms that can cause disease in humans or animals. There are many microorganisms that in general do not infect or act as commensals, but in a situation of compromised immunity of the host, these microorganisms cause diseases. These types of pathogens are called opportunistic pathogens; they are mainly bacteria or fungi, but sometimes, protozoa and viruses can also behave like opportunistic ones. Many times routine detection methods even with PCR or isothermal techniques are time-intensive and require sophisticated instruments, and highly proficient personnel, which makes this type of method not very useful in point-of-care treatment (POCT). A new emerging technology based on Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated nuclease (Cas) sensing (CRISPR-Cas) system is a powerful tool for anything from genome editing to disease-causing pathogen identification. This specific and sensitive system has a high potential to become one of the leading detection systems for POCT. This chapter summarizes the various methods of detection based on CRISPR-Cas system on different opportunistic pathogens.