ICD-10 · R50.9
Fever
Fever is a temporary rise in body temperature above 38°C (100.4°F), usually a sign that the immune system is responding to an infection. In India the most common causes are viral illness, dengue, typhoid and malaria, so any fever lasting more than three days needs testing rather than repeat self-medication.
Symptoms
Body temperature above 38°C, chills and shivering, sweating, headache, muscle aches, loss of appetite, weakness and dehydration. Warning signs include rash, bleeding gums, persistent vomiting, breathlessness, confusion or a fever that returns after settling.
Causes & risk factors
Viral infections (influenza, dengue, COVID-19), bacterial infections (typhoid, urinary tract infection, pneumonia), malaria, post-vaccination immune response, heat exhaustion, and inflammatory conditions. Mosquito-borne fevers peak in India during and after the monsoon.
Diagnosis
Temperature measurement plus history and examination. Depending on the pattern, doctors order a complete blood count, dengue NS1/IgM, malaria smear or rapid test, Widal or blood culture for typhoid, urine routine, and chest X-ray if cough is present.
Treatment options
Paracetamol is the first-line fever reducer for adults and children in India; the usual adult dose is 500–650 mg every 6 hours, not exceeding 4 g a day. Avoid NSAIDs such as ibuprofen or aspirin until dengue is ruled out because they increase bleeding risk. Fluids, oral rehydration solution and rest matter as much as medicine. Antibiotics help only when a bacterial cause is confirmed.
When to see a doctor
Fever above 40°C, fever lasting more than three days, fever in an infant under three months, rash or bleeding, severe headache with neck stiffness, breathlessness, reduced urine output, or drowsiness.