PCR detection holds great significance in dealing with human Infectious Diseases. Clinically, it can rapidly identify the specific pathogens causing infections, be it bacteria, viruses or fungi. For diseases like COVID-19, PCR tests provided quick and accurate diagnosis in a short time, guiding timely isolation and treatment. It can also detect emerging or mutated pathogens, helping public health officials to take preventive measures promptly. Moreover, PCR allows for monitoring the effectiveness of treatment, as the decline in pathogen load can be tracked. In essence, it's a powerful tool safeguarding public health against infectious threats.