This work shows a world overview of the SARS-CoV-2 diagnostic methods, analyzing their effectiveness and sensitivity. With a special emphasis on biosensors, specifically, those that are based on fiber-optic technology, explaining simply their operation and their ability to detect diseases such as SARS-CoV-2. With these technological advances, the clinical diagnosis will be made: faster, cheaper, and applied to patients in remote places where there are no hospitals or clinical laboratories, either due to poverty, geographic difficulties, or violence, factors found in Colombia.