Michael Mina, professor of epidemiology at Harvard, has been campaigning for weeks for what he has called shoddy, “suck” or more colloquially “crappy” tests. The idea is to break away from the current model of high precision molecular tests (PCR tests), which are still too rare in a large part of the United States, for which people often queue for hours, and wait. days, or even a week, for results.
He proposed that the US Medicines Agency (FDA) authorize the marketing of rapid tests, done at home from a strip of paper that would change color in a quarter of an hour to give the result, like a pregnancy test.
These tests have low sensitivity, i.e. they miss a lot of positive cases and therefore give a lot of “false negatives”, but for Michael Mina and other experts, this strategy would be more effective in terms of public health since at the population level, the number of identified cases would be greater than at present.
These rapid tests are good on average at detecting people who shed a lot of viruses, that is, when they are very contagious, at the very beginning, while PCR tests are very sensitive and even detect low concentrations of the virus. , which happens at the end of the illness, when people are hardly contagious anymore.
“We are so attached to high-end and expensive testing that we don’t test anyone,” said Michael Mina recently in the This Week in Virology podcast. “Maybe we just need a null test. If it is cheap enough to be used frequently, then it will maybe detect 85% of people with contagious disease, instead of less than 5% “.
The director of the Harvard Global Health Institute, Ashish Jha, returned to the charge on Monday.
“These tests are not that bad,” he told reporters. “When you are very contagious, and you have a lot of viruses in your throat and elsewhere, the test improves a lot.” However, “from an epidemiological point of view, this is exactly the moment when we want to detect people”.
Even if the rapid test misses half of the cases, it is likely that with two tests per week, it will eventually catch them.
All recall that in addition, the current system misses nine cases out of ten, since relatively few people are tested, according to the estimates of the Centers for the fight against diseases.
The FDA has yet to clear any of these strip tests, which are said to cost between $ 1 and $ 5.
“I fear that our federal government is stuck in an insane thinking pattern for this pandemic,” said Ashish Jha.
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