Question

why thermal screening cannot detect people who are infected but not sick​

Answer 1

Explanation:

Thermal scanners cannot detect people who are infected but are not yet sick with fever. This is because it takes between 2 and 10 days before people who are infected become sick and develop a fever.

Answer 2

Answer:

Thermal scanner can't detect the people who are infected by some disease  but are sick with fever or cough. The reason behind this is that it takes 2 to 10 days people who are infected become sick and develop a fever