Hi I can understand your concern. Your baby has fever since last three days and already on antibiotics. Typhoid blood test ie Widal test is to be done after ten days of fever to consider it s interpretation. Before that only blood culture can tell you about typhoid. I would suggest you to monitor his fever. Give paracetamol ten mg per know six hourly. Continue with antibiotic and nutrition Be. Look for any other associated symptoms. Wait for two days. If fever persists in increasing trend and frequency then consult pediatrician for diagnosis and treatment accordingly. If baby is playing and active when not febrile then more likely this could be a viral infection. Meanwhile let her drink plenty of water and fruits. Hope this helps you.