Contract tracing hasn't worked at scale anywhere. It's a nice idea conceptually, but the problem is psychological. People stop caring about tracing when 98% of all trace connections are false positives. If a person is infectious for a week and the r0 is around 1 then only 1 person of all the people they've been in contact with will actually contract the virus on average. The other 50+ people, assuming they can even be traced, get a false positive. Or to put it differently, people have to be called 50 times and get tested and self-isolate 50 times before they actually test positive. And for younger people 80% of cases are completely inconsequential. You might think 50 contacts is unrealistically high, but most people still go to work, to school, see friends, use public transportation, etc.
Covid19 would also be over if people with symptoms would just stay home. But that's clearly not happening either. We've got to be realistic about how people behave in the real world.
Mutations aren't a serious concern. Because when viruses mutate it's the strains that are more infectious and less lethal that win out.
Covid19 would also be over if people with symptoms would just stay home. But that's clearly not happening either. We've got to be realistic about how people behave in the real world.
Mutations aren't a serious concern. Because when viruses mutate it's the strains that are more infectious and less lethal that win out.