CLARIFICATION:
Much confusion about rapid antigen tests
ALL evidence - when evaluated appropriately! - shows these are VERY good at detecting infectious virus
• ~100% if used frequently
• >95% for single samples with high, most likely contagious viral loads
The tests work
Much confusion about rapid antigen tests
ALL evidence - when evaluated appropriately! - shows these are VERY good at detecting infectious virus
• ~100% if used frequently
• >95% for single samples with high, most likely contagious viral loads
The tests work
We've been evaluating rapid Ag tests on campuses. We find these tests - when used as screening w/out symptoms DO miss most PCR positives!
BUT EXPECTED! - ALL misses were previously detected and already finished isolation.
Ag is MUCH more specific than PCR for contagious virus
BUT EXPECTED! - ALL misses were previously detected and already finished isolation.
Ag is MUCH more specific than PCR for contagious virus
this is the whole point of rapid antigen tests - they find people who are currently infectious. They are fast, give crucial immediate results and unlike PCR do NOT stay positive for weeks/months after someone is no longer infectious.
This is also at the center of why people keep confusing them as low sensitivity. They simply cannot be compared against PCR RNA positives. PCR RNA remains positive LONG after someone is infectious. Making PCR a poor tool for knowing who requires isolation.
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