On the other hand, if you tested everyone using this strategy and quarantined those who tested positive, you'd eliminate Covid in two months.
If adding a magic doggie in to deliver the news would help compliance, all the better!
If adding a magic doggie in to deliver the news would help compliance, all the better!
You have too much confidence in that statement.
If false positive, false negative, and prevalence rates are all 5%, and let's say you subject 350,000,000,000 people to the dog test (ignoring the time it takes to do that and logistical difficulties with having enough dogs and handlers etc).
9.5% of society tests positive resulting 33,250,000 total positive results. Half of this number are true positives and half are false positives. That means, quarantining 16,625,000 uninfected people along with 16,625,000 infected people which results in the loss to society of their output and might also now get them infected depending on how they are quarantined.
Out of the 17,500,000 people who are infected, there will be 875,000 false negatives who will not be quarantined who will continue to spread the infection. In fact, 5% false negative rate sounds kind of optimistic. If false negative rate is 25%, 4,375,000 infected people will not be detected using this method.
You can play with the numbers using this calculator[1].
Second, let's say you put a dog at every company and every day everyone needs to be sniffed on the way in. If the false positive rate is 5%, the probability that you will not be quarantined due to a false positive during the year is 0.95*250 approx = 0.0003%.
[1]: https://www.covid2020.icu/false-positive-false-negative-simu...
What you are suggesting is to ignore the possibility that dog sniffing may result in false negatives, and administer a "real" test to anyone who's identified by a dog to be positive. Keep in mind that under reasonable assumptions, half of those people are false positives. A portion of them will falsely test positive again. However, some of the true dog test positives (anywhere between 2% - 25% of them) will falsely test negative. Therefore, this strategy will result in more infected people not being quarantined.
You do accurately describe the issue with relying solely on tests with false negatives to control Covid.
I had assumed your comment was sarcastic.
Note that if you believe prevalence is 95%, there is no reason to spend any resources on dogs, tests, or even vaccines.
Making all that effort only makes sense in a world where prevalence is assumed to be low and the effort is to keep it low.
So, let's say prevalence is 5%. Then, you method has a false positive rate of 95%. Are you OK with the implications of that?
Not to mention a ton of other illnesses. I do wonder if “the world’s governments pay everybody to stock up on food and stay home for two months” would actually be a huge win for humanity, and maybe even in the short-term it would work out cheaper than two years of 75%-lockdown :P
What's that going to do other than to cause the price of "food" to go up and cause a bunch of people to die in the worst Black Friday reenactments?
Note that while it is possible to calculate a weighted price index of food, people do not eat the weighted average of all food sold.
It is fantasies of control by people that got us to the point where every day every where governments are burning away their countries' wealth and their citizens' futures.
The quotation marks are misleading because I never referred to government control. Instead, I am referring to the "fantasy of control."
However, now that you mentioned it, in these countries with low observed infection rates, are people free to gather in groups? Are they allowed to engage in usual activities? Are they allowed to travel freely?
If the answers to those and similar questions are not all no, then, clearly not everyone is willingly isolating themselves, and people who entertain fantasies of control or directing the power of government to limit their freedoms.
They have done so without ever paying attention to the costs of such limitations on the usual functioning of human beings.
As for the freedom of gathering - we already know that with just a few weeks of not being in contact we can protect ourselves, our families and each other. There’s no martial law or curfew imposed on us - just a lockdown or a Circuit Breaker that we’ve seen as inevitable.
But somehow spreading deadly disease is you essential liberty