evidence: Tests that detect current infections with SARS-CoV-2, the virus that causes COVID-19, are known as viral tests. There are two types: a Nucleic Acid Amplification Test, or NAAT, and an antigen test. [...] The Centers for Disease Control and Prevention says NAATs "are unlikely to return a false-negative result of SARS-CoV-2," and it recommends laboratory-based NAATS, the most sensitive tests, to confirm infection. An antigen test is designed to detect a SARS-CoV-2 protein, typically the nucleocapsid protein. Also conducted via a nasal or throat swab, antigen tests are less sensitive than NAATs but inexpensive and can usually produce results in about 15 minutes. Getting a result from a laboratory-based NAAT test can take hours or even a few days.