If I understand correctly, measles can be very contagious 4 days before rashes appear (through respiratory droplets from coughing). I think a person could mistakenly think they just have a cold or flu (or Covid) before rashes appear. It can also have a ~12 day incubation period without symptoms (but I don't think it's very contagious before symptoms appear).
If I understand correctly, measles can be very contagious 4 days before rashes appear (through respiratory droplets from coughing). I think a person could mistakenly think they just have a cold or flu (or Covid) before rashes appear. It can also have a ~12 day incubation period without symptoms (but I don't think it's very contagious before symptoms appear).