**4. Conclusion**

Taking into account the present situation of a pandemic it becomes extremely essential to develop a fast, effective, risk-free, and reliable method for diagnosis of COVID-19. There are several diagnostic methods available today for detecting the virus but each method has its pros and cons. Attributes such as accuracy level, complexity of instrumentation, the need for sample preparation & purification, operational and capital cost, time, geo-spatial availability, high technical skills and so on are to be considered before finalizing the best method of testing. The use of RT-PCR diagnosis for the virus is common and widely used everywhere due to its higher accuracy, sensitivity and reliability but due to its expensiveness, it cannot be afforded by lower incomes countries and is also a not suitable method for screening a large population at a time. Many new diagnostic methods such as RT-LAMP and CRISPR based technologies are also emerging which provide rapid, user-friendly, higher specificity & sensitivity, efficient and low-cost diagnosis of SARS-CoV-2 and can be deployed on the airports, office buildings, schools, etc. due to their nature of the simple operation, however, CRISPR has a little risk of contamination associated with it. Rapid serological methods based on antibodies/antigens are proving to be faster tests but not always give faster results and are not recommended because of their limited research. Currently to overcome the COVID-19 pandemic developing rapid, reliable, and novel biosensors for the detection of the virus is of much interest and will prove to be paradigm altering in surveillance, once perfected. The development of new SARS-CoV-2 biosensors is focused on the detection of biomarkers from human hosts, rather than antibodies or immunoglobulins. Developing sensitive, space-friendly, and portable biosensors can prove beneficial for the quick diagnosis of the virus.

With diagnosis, another important aspect is the assessment of disease prevalence in an area. The infection spread of SARS-CoV-2 is rapid and mostly happens through air, hence checking the prevalence of disease only after appearance of symptoms may not help in controlling the spread of virus. For that, advanced tools such as GIS or modeling techniques have to be used which can act as an early warning system. The GIS technology enables the local authorities as well as general public to recognize particular hotspots and take preventive measures in the right time. GIS based platforms and models can help in management of spread

#### *Evolution of Diagnostic Methods and Prevalence Detection of COVID-19: A Review DOI: http://dx.doi.org/10.5772/intechopen.99241*

of virus through visualization and data analytics. Many tools and techniques use GIS for contact tracing and identification of containment sites. Another way the early warning system can be established is through wastewater sample analysis for analysis of virus. The time lag functions can be developed for various areas through thorough sampling and analysis of wastewater and disease prevalence in the area in order to understand the disease progression and forecast in that area. While this chapter discusses major techniques used for diagnosis and prevalence of COVID-19 among the population, the researchers are continuously working on finding better methods. The chapter comprehensively covers the methods being used currently for targeting and managing the spread of this virus and should helpful in getting an overview related to the tools and techniques being used for the assessment.
