Currently, worldwide, the reverse transcriptase-polymerase chain reaction (RT-PCR) is used as a high-precision technique in detecting and amplifying specific sections of the genetic structure. In this sense, it is considered a molecular diagnostic test in the detection of SARS-CoV-2. A review of the literature was carried out on articles published in the last 5 years (2015-2020). The following databases were consulted: PUBMED (Medline), PUBMED CENTRAL, and SCIELO. Articles in Spanish and English were retrieved, according to MESH terminology: SARS-CoV-2, RT-PCR, COVID-19. RT-PCR tests that use nasal and pharyngeal swab samples are considered the standard gold test in suspected cases of COVID-19. Through the South American review of molecular tests, RT-PCR turned out to be the test of choice in the countries of South America during the period less than 7 days of infection, highlighting the in-house production in scale by Uruguay and the Loop-mediated isothermal amplification test (RT-LAMP) adapted in Peru as a rapid diagnostic alternative with principles similar to RT-PCR, only for health facilities with less equipment, infrastructure, and trained personnel. The availability of molecular diagnostic tests is also crucial for isolating positive cases and monitoring the epidemiological chain of transmission.