What is an antigen test and how does it work?

Table of Contents

1. Introduction to Antigen Tests
2. Mechanism of Action
3. Comparison with Other Testing Methods
4. Immuno Company Solutions
5. References

Introduction to Antigen Tests

Antigen tests are diagnostic tools used to detect the presence of antigens, typically proteins, on the surface of pathogens such as viruses. They are commonly used in identifying infections caused by viruses like SARS-CoV-2, the virus responsible for COVID-19. Antigen tests provide rapid results, making them useful for quickly identifying and isolating infected individuals.

Mechanism of Action

Antigen tests work by utilizing antibodies that specifically bind to antigens present on the surface of the pathogen. Here's a step-by-step explanation of how an antigen test operates:

1. Sample Collection: Typically, a nasal or throat swab is used to collect a sample from the patient.
2. Application: The sample is applied to a test device containing antibodies that recognize and bind to the target antigen.
3. Reaction: If the target antigen is present in the sample, it will bind to the antibodies, forming an antigen-antibody complex.
4. Signal Development: The test device contains a detection mechanism, often a color change, indicating the presence of the antigen-antibody complex.
5. Result Interpretation: Results are read visually or by a machine, indicating either a positive or negative result for the presence of the antigen.

Antigen tests generally offer a sensitivity between 50% and 80%, and specificity rates are often greater than 98%, depending on the test design and pathogen.

Comparison with Other Testing Methods

Compared to polymerase chain reaction (PCR) tests, antigen tests offer faster results, usually within 15-30 minutes. However, PCR tests are typically more sensitive and can detect lower quantities of viral material, leading to higher accuracy. Antigen tests are a cost-effective alternative for mass screening, especially in settings where rapid diagnosis is essential.

Immuno Company Solutions

Several companies specialize in producing reliable antigen tests. These solutions offer advanced features for improved accuracy and ease of use:

1. ImmunoTech Rapid Test: Offers a sensitivity of 85% and a specificity of 99%. Designed for convenient home and clinic use, providing results in under 20 minutes.
2. QuickAntigen+ Kit: Utilizes enhanced signal amplification technology, resulting in a sensitivity of 90% and a specificity of 99.5%. Suitable for large-scale testing in community settings.
3. AntigenSure Pro: Focuses on specific antigen markers to improve sensitivity (92%) without sacrificing specificity (98%). Ideal for high-risk environments like hospitals and nursing homes.

References

1. Bullard J, Dust K, Funk D, et al. Predicting infectious SARS-CoV-2 from diagnostic samples. Clin Infect Dis. 2020.

2. Scohy A, Anantharajah A, Bodeus M, et al. Low performance of rapid antigen detection test as frontline testing for COVID-19 diagnosis. J Clin Virol. 2020.

3. World Health Organization. Antigen-detection in the diagnosis of SARS-CoV-2 infection. September 2020.