pooled, antigen testing¶
I'm going to lay out the ineffectiveness of schools relying on weekly, pooled, antigen testing with a case study, keeping in mind both the realities on the ground and the science. In this case, we'll imagine an 8th grade teacher who gets infected outside of school. Maybe their spouse got it from work. Maybe they got it at a packed grocery. Either way, this teacher was fully vaccinated and always wears a mask, but still caught COVID anyway. Bad luck. The teacher got infected on Sunday evening, but doesn't realize yet.
Monday through Thursday, they go to work, teaching 30 students per class, for a total of 120 students over the course of a day.
On Thursday, it's time for testing. 32 of the students did not opt in. On Friday, the teacher develops symptoms and stays home. None of the students have symptoms, and are still in school that day, even though 8 of them caught COVID from their teacher. By the end of the day, 2 more students have been infected. The results of the pooled test come in and there is a positive case. This means everyone in the pool is now supposed to receive an individual test. Since it's now Friday afternoon, this will have to happen on Monday. Over the weekend, the 10 infected (but asymptomatic) students spread the infection to 12 family members.
On Monday, 2 of the infected students stay home with symptoms. The other 8 return to school and participate in individual antigen testing. During lunch on Monday, 6 more students get infected, since everyone needs to take off their masks to eat.
By Monday evening, individual results come in. Because antigen tests are less sensitive, and they are asymptomatic, only 4 students test positive and are told to quarantine By Tuesday, there are 10 infected students, none of whom are even aware.
By Thursday, 2 more have developed symptoms and stayed home without testing. 12 more students have been infected. Time to test again! Results will come in tomorrow, by which point 2 more will be infected. By the time we've gone through 2 rounds of weekly testing, 40 students, 50 family members, and an unknown number of family members' coworkers have all been infected. And we will still have infected students coming in next Monday to continue the cycle.