 [ Symptoms ] can warts on hands spread to genitals [ Disease ] hi notice that if your on higher dose than you should of thyroxine to treat hashimoto then it can cause low grade persistant fever low grade persistant fever has many causes however in your case you are showing no other significant symptom beside being tired and sleepy did you get in contact with animals lately so possibilitys are no 1 rickettsia which is caused by gram negative infection which means blood and urine cultures won t usually show it unless you are specifically looking for it no 2 chlamydia psittaci infection no 3 hiv no 4 cancer good luck