Fever is a common problem in children. Temperature greater than 100.4 degree Fahrenheit (38 C) measured rectally or through ear thermometer is labelled as fever. When temperature is measured in the mouth, temperature of 100 degree F, and in the axilla 99 degree F is labelled as fever.
Most common cause of fever is viral infections. Fever may be the only symptom for the first 24 hours (i.e., viral fevers). The onset of symptoms (runny nose, cough, diarrhea, etc.) are often delayed. The cause of the fever usually can't be determined until other symptoms develop. That may take 24 hours. Viral infections get better on their own and antibiotics are not needed for these. See the section on 'cough and cold' for further detail on viral infections.
If fever lasts more than three days, or if there are no associated viral symptoms at all after two days of fever, or if at any point the child appears unwell, is lethargic, irritable, not eating or drinking, then a physician should be promptly consulted and other causes besides viral infections should be explored. There are many causes of fever besides viral infections in Pakistan, and they include Typhoid, Malaria, Dengue etc. Please consult your doctor who will advise proper work up and treatment. Antibiotics should generally be prescribed only after appropriate tests are done.
Remember that fever in a child less than three months old children is an emergency and must be promptly evaluated.