Rapid Antigen Testing

Lateral flow paper strip tests are uniquely scalable — even small startups with manufacturing partnerships can produce millions of strips per week. True lateral flow paper strip tests can potentially cost under $1 per test and require no equipment, instrument, or connectivity. Antigen tests are better than PCR at distinguishing currently infectious individuals from post-infectious individuals. Antigen tests lose approximately one day of detection at the very start of infection compared to PCR, during which a person is unlikely to be efficiently transmitting. Rapid antigen tests do not register a positive signal until viral load reaches approximately 100,000 particles per milliliter, roughly 100-fold higher than PCR's detection threshold. The bottleneck to mass antigen test production is regulatory authorization, not manufacturing capacity. Rapid antigen tests should be classified and evaluated as public health surveillance tools, not as diagnostic tests.