Do you have a sore throat? If so, visualize gold energy engulfing and soothing your throat, drink loads of tea, eat soup, stay warm, take meds if the fever gets very high. You should clean your aura with just visualisation alone until your throat gets soothed.
If it's just exhaustion, fever and sickness without sore throat, then do a raised amount of Aura and chakras cleaning, do an AoP as well and make sure to rest and don't exhaust yourself.