Dengue, Typhoid or Viral Fever? How to Tell and When to Get Tested
Fever in Hyderabad after the rains? Learn how dengue, typhoid and viral fever differ, which test to do on which day, and warning signs that need hospital care.
By Dr Sujith ChadalaMBBS, MD (General Medicine)
Why fever is so common after the monsoon
Every year from July to November, clinics in Hyderabad see a surge in fever. Standing water allows the Aedes mosquito, which spreads dengue, to breed, while contaminated water and food spread typhoid. Seasonal viral infections circulate at the same time. In the first two or three days, all three can look very similar.
How they usually differ
| Viral fever | Dengue | Typhoid | |
|---|---|---|---|
| Onset | Sudden | Sudden, high fever | Gradual, rising over days |
| Typical symptoms | Cold, cough, sore throat, body ache | Severe body and joint pain, pain behind the eyes, rash | Abdominal discomfort, loss of appetite, headache, constipation or loose motions |
| Usual course | Better in 3–5 days | Fever 2–7 days; platelets may fall as fever settles | Persists beyond a week without treatment |
| Key tests | Usually none | CBC, NS1 (early), IgM (after day 5) | Blood culture, CBC |
These are patterns, not rules. Many people do not fit neatly into one column, which is why examination matters.
Which test on which day?
- Days 1–5 of fever: dengue NS1 antigen and a complete blood count (CBC).
- After day 5: dengue IgM antibody becomes more useful.
- Suspected typhoid: blood culture before any antibiotic is started.
- Malaria: a peripheral smear or rapid antigen test.
Testing too early or too late can give a falsely reassuring result, so tell the doctor exactly which day the fever started.
What you can do at home
- Drink plenty of fluids — water, ORS, coconut water, soups.
- Use paracetamol for fever and pain. Avoid ibuprofen and aspirin until dengue is excluded.
- Rest, and check your temperature two to three times a day.
- Do not start antibiotics on your own. They do not help viral fever or dengue.
Warning signs: go to hospital now
- Severe abdominal pain or vomiting that does not stop
- Bleeding from the gums or nose, black stools or blood in vomit
- Very little urine, cold hands and feet, dizziness on standing
- Breathlessness, drowsiness or confusion
- Fever in an older adult or someone with diabetes, kidney or heart disease who is getting worse
Call 108 or go to the nearest emergency department if any of these appear.
When to see a physician
See a doctor if fever lasts more than two to three days, is very high, comes with any of the symptoms above, or if you are older or have a long-term condition. Learn more about fever and infection care or book a consultation.
Frequently asked questions
Is the Widal test reliable for typhoid?
The Widal test is often falsely positive in India because of past infections or vaccination. A blood culture, taken before antibiotics, is the most reliable test for typhoid.
Can I take paracetamol for dengue?
Yes, paracetamol at the recommended dose is the preferred fever medicine. Avoid ibuprofen, diclofenac and aspirin because they can increase bleeding risk.
When is the most dangerous phase of dengue?
The critical phase is usually when the fever comes down, around days three to seven. Warning signs such as abdominal pain, persistent vomiting, bleeding or drowsiness need immediate medical attention.
This article is for general education only and is not a substitute for professional medical advice, diagnosis or treatment. Please consult Dr Sujith Chadala or another qualified doctor about your specific situation. Created with AI assistance.