Fever (pyrexia)

Fever — body temperature above 100.4°F (38°C) — is the body's response to infection or inflammation. In Tier-2 India the typical causes shift with the season: viral fevers (including norovirus and seasonal flu) year-round, dengue and chikungunya during and after the monsoon, typhoid through warmer months, malaria in some pockets, and COVID-19 still occasionally appearing in waves.

When fever is worrying

Most viral fevers settle in 3-5 days. The ones that need attention:

• Fever above 102°F (38.9°C) lasting more than 24 hours, especially with chills.
• Fever in an infant under 3 months — always come in.
• Fever in someone immunocompromised (cancer treatment, post-transplant, severe diabetes).
• Fever with a rash.
• Fever with severe headache and neck stiffness (rule out meningitis).
• Fever with breathlessness.
• Fever that comes back after seeming to settle.
• Fever lasting more than 5 days.

What we test

Standard workup at Asian Hospital for a fever > 48 hours: CBC, CRP, dengue NS1 + IgM, malaria smear or rapid test, Widal (after the 5th day for typhoid), urine routine, sometimes chest X-ray. The pattern of results combined with the timeline narrows down the cause in most cases within a single OPD visit.

What to do at home

While you arrange a doctor visit: paracetamol 500-1000 mg every 6 hours (max 4 g/day in adults). Plenty of fluids. Rest. Avoid wrapping in heavy blankets — that traps heat. Cool sponging is safe if temperature is very high. Avoid aspirin (especially in children — risk of Reye's syndrome) and avoid antibiotics without a doctor's prescription (most fevers are viral; antibiotics don't help and create resistance).