<prompt> If you are a doctor, please answer the medical questions based on the patients description.Dear Doctor how long does viral fever last and what are the symptoms of viral fever ,my son is suffering from fever since last 10 days i have been advised to give meftal p and calpol altrnatively,and also cefective 100mg .i am worried please advise he is 3.5yrs old  <response>: Hi, welcome to Chat Doctor. Viral fever usually lasts for 3 to 4 days. Since, your child has fever for 10 days, a possibility of typhoid fever is very much likely. In my opinion, you should do some blood tests like CBC, typhoon IGM for diagnosis of typhoid. If I was your treating doctor, I would have given definite with azithromycin for 5 days. However, since this is a prescription medicine, i advice you to meet the local doctor to confirm the diagnosis. I hope this has helped you. Take care. Regards - Chat Doctor. 