Dengue in Delhi: when to test, and what a falling platelet count means
NS1 works early, antibodies work later — testing on the wrong day gives a false reassurance. What to watch for, and the warning signs that mean hospital, not home.
Delhi sees a dengue surge every year after the monsoon, roughly September through November. Testing at the right moment makes a real difference to how useful the result is.
Timing decides which test works
Dengue testing has a sequence, and this is the single most misunderstood part:
- NS1 antigen detects the virus itself. It is reliable in the first five days of fever and becomes progressively less so afterwards.
- IgM antibody appears from around day five, as the body starts responding.
- IgG antibody indicates past infection, or a repeat infection.
Test on day two with antibodies alone and you may get a negative in someone who genuinely has dengue. Test on day eight with NS1 alone and the same thing can happen. This is why a combined NS1 + IgM + IgG panel is the sensible default when the day of illness is uncertain.
Why the platelet count is repeated
A complete blood count matters as much as the dengue test itself. Platelets typically fall from around day three, reach their lowest point near days five to seven, and recover afterwards.
What doctors watch is not a single number but the trend, which is why they ask for a repeat count every day or two during the illness. A stable count of 90,000 is far less concerning than one that has dropped from 150,000 to 90,000 in a day.
Warning signs — seek care immediately
The dangerous phase of dengue often begins as the fever falls, which is exactly when people assume they are recovering. Go to a hospital without waiting for a test result if there is:
- Severe abdominal pain
- Persistent vomiting
- Bleeding from gums or nose, or blood in vomit or stool
- Black, tarry stools
- Restlessness, confusion, or unusual drowsiness
- Cold, clammy skin
- A sudden drop in urine output
Managing the milder course at home
Most dengue is managed at home with rest and fluid. Two points worth stating plainly:
Take paracetamol for fever. Avoid ibuprofen, aspirin, diclofenac and similar anti-inflammatory painkillers — they increase bleeding risk, which is the specific danger in dengue.
Fluid intake matters more than most people expect. Plain water, ORS, coconut water, soups. Dehydration is what turns manageable dengue into a hospital admission.
Papaya leaf extract
It is widely used and widely asked about. The evidence for a meaningful effect on platelet counts is weak and inconsistent. It is not a substitute for monitoring, fluids, or medical attention — and if it delays someone seeking care for the warning signs above, it does harm.
General information, not medical advice. Fever with any warning sign needs same-day medical assessment.
Tests mentioned in this guide
Common questions
On which day of fever should I get a dengue test?
NS1 antigen is most reliable in the first five days. From day five, IgM antibodies become useful. A combined NS1 plus IgM and IgG panel covers both windows.
How low do platelets have to be before it is dangerous?
There is no single number — the trend matters more than a snapshot, and clinical warning signs matter more than either. Severe abdominal pain, persistent vomiting or any bleeding needs immediate care regardless of the count.
Can I take ibuprofen for dengue fever?
No. Avoid ibuprofen, aspirin and similar anti-inflammatory painkillers, which increase bleeding risk. Paracetamol is the appropriate choice.
Do I need to repeat the blood count?
Usually yes. Doctors typically repeat the platelet count every day or two through the illness, because the direction of change is what guides decisions.