What is the measure of the temperature you feel (or perceive) when humidity is added to temperature?

The measure of the temperature you feel (or perceive) when humidity is added to temperature is the heat index (HI). This measure combines the physical quantity temperature and the humidity, which depends on temperature and the pressure of the system we analyze. The idea is to better capture the human-perceived temperature and it is also called "apparent temperature". The heat index is measured in Fahrenheit. 

Its decreasing because of illnesses

Ansradar; im guessing here; good luck : )