Clinical Guidelines from IAP state that oral Cefixime (Monocef-O) is the first line antibiotic. However, antibiotic-resistance in Salmonella is growing, & so if fever is not improving, you will need revision of antibiotic, depending on the antibiotic-sensitivity pattern (hopefully culture would have been taken prior to starting Cefixime)
Next Steps
Review with pediatrician with your concerns regarding persistent high fever