COVID-19 Testing: The Basics
COVID-19 testing is a fast-growing field that is evolving as our understanding of SARS-CoV-2 improves and more test manufacturers enter the market. Whether you are taking a test prescribed by your doctor or choosing a test for your organization, it is important to choose the right type of test to give you the most useful information.
COVID-19 testing can be categorized into 2 main groups: testing for active SARS-CoV-2 infection or testing for past SARS-CoV-2 infection. Active infection indicates that a person has virus that is replicating and that they could infect others. Past infection indicates that an individual has recovered from COVID-19 and has no actively replicating virus.
![Antigen and molecular tests Antigen and molecular tests](/sites/default/files/styles/rich_text_half_size/public/2024-04/test-types-molecular.jpg?itok=4rsjsKuJ)
To test for active infection, diagnostic antigen or molecular tests are used. Antigen rapid tests detect the presence of viral proteins (antigens) in a patient sample and can provide results in under a half hour. In contrast, molecular tests amplify existing viral genomic material from a patient sample. These tests can detect if a patient has a current infection, which can help patients and healthcare providers make decisions about treatment and isolation to reduce spread.
![Serology tests Serology tests](/sites/default/files/styles/rich_text_half_size/public/2024-04/test-types-serology.jpg?itok=HpTJT2ss)
To test for past infection, serology tests are used. Serology tests detect the presence of antibodies produced by our immune system in response to a pathogen and are specific to certain proteins (antigens) of those pathogens. The presence of antibodies specific to SARS-CoV-2 indicates that a person was exposed to the virus and is currently seropositive for SARS-CoV-2-specific antibodies.
Defining the Accuracy of Tests
Diagnostic Approval Process During the COVID-19 Pandemic
Glossary: COVID-19 Testing Technical Terms
Considerations for Developing a COVID-19 Testing Strategy
Variants of Concern (VOCs) and Testing
Variants Vaccines and What they Mean for COVID-19 Testing
Webinar Series: Lessons Learned from Organizations Implementing Testing Strategies
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