Dr. Michael Mina:

Not at all. It is just an inaccurate assessment. If the goal, again, is to limit and block transmission and track transmissible people, the mathematics is very simple. I will give an example that everyone can understand. A person is positive on a PCR for about 30 days. We know the isolation window proposed by the Centers for Disease Control and Prevention, CDC, is only ten days. The WHO has seen that a ten-day isolation window is appropriate. That means ten days is the maximum infectious period, but with a PCR positive test it is 30. Doing the simple division of ten days of transmissibility divided by 30 days of being PCR positive, means that only around 30% to 40% sensitivity should be expected of a transmission-indicating test when comparing it against PCR. A 50% accuracy rate is actually a good value when comparing a test with PCR. If that test is only supposed to detect infectiousness, the accuracy rate should only be somewhere between 20% and 50%, taking variants into account. It should not be more than 50% sensitive. The other 50% that is being missed are almost always people who are post-infectious in those 20 days after the isolation period.