influenza
"I was swabbed and diagnosed with Influenza Type A - H2N3.  I started Tamiflu about 18 hours after initial symptom onset.  Two days after starting Tamiflu, the worst symptoms are almost entirely gone.  I am still fatigued and have some respiratory crud, but the severe headache, muscle and joint pain, and fever are gone.  I have some minor, transient nausea, but I don't know if that's the medicine or the illness. 
"