CRISPR-Based Detection of Viral Hemorrhagic Fevers at the Point of Care

Viral hemorrhagic fevers (VHFs) are highly lethal diseases that often present non-specific, influenza-like symptoms in their early stages, making clinical recognition and differentiation from other febrile illnesses difficult. This overlap underscores the critical need for diagnostic tests that are both sensitive and specific. Point-of-care (POC) diagnostic tests are an invaluable tool for detecting and controlling the spread of pathogens that threaten public health, such as VHFs, as these require fast, accurate diagnostics to ensure biosafety and appropriate mobilization of resources during outbreaks. Current molecular and serological diagnostic tests, while efficient and effective, lack the characteristics required of a POC test (POCT) to quickly and easily respond to a VHF outbreak while maintaining a low cost. Clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostic tests have gained popularity as POCTs due to their inherent attractive qualities, including high sensitivity and specificity, adaptability, low cost, quick turnaround time, and ease of use. However, studies on the development of CRISPR-based POC diagnostic tests for VHFs are limited. This review summarizes the current CRISPR-based POCTs for VHFs, including Ebola virus (EBOV), Lassa virus (LASV), Dengue virus (DENV), and Crimean-Congo hemorrhagic fever virus (CCHF). The isothermal pre-amplification methods commonly paired with CRISPR-based tests, such as loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA), are also discussed.