Dengue Fever
Dengue is a viral infection spread by the Aedes mosquito, which bites in daylight and breeds in small collections of clean standing water — a cooler tray, a plant pot, an uncovered tank. In Punjab it peaks from late August to November, after the monsoon. Most people have a hard week of high fever, severe headache, pain behind the eyes, aching muscles and joints, and a rash, and recover completely. The danger is not the fever: it is the critical phase on days three to seven of illness, which usually begins just as the temperature comes down and the patient appears to improve. In that window fluid can leak out of the blood vessels, and the warning signs are severe abdominal pain, repeated vomiting, bleeding from the gums or nose, blood in vomit or stool, restlessness or drowsiness, cold clammy skin, and passing much less urine than usual. Any one of those means going to hospital immediately. Treatment is fluid, monitoring and paracetamol; aspirin, ibuprofen, diclofenac and injections into muscle must be avoided because they increase bleeding. A falling platelet count is monitored rather than treated on its own, and platelet transfusion is a hospital decision made for bleeding, not for a number. Papaya leaf juice, goat milk and kiwi do not treat dengue, and the hours spent obtaining them are the hours that matter most.
Health writers · Aslam Clinic
What dengue is
Dengue is caused by a carried by the Aedes aegypti mosquito. There are four types of the virus, called serotypes, and infection with one gives lasting protection against that type only. That is why a person can get dengue more than once, and why a second infection with a different serotype carries a higher risk of the severe form.
The mosquito matters as much as the virus. Aedes bites during the day, most actively in the two or three hours after sunrise and before dusk. It breeds in small volumes of clean water close to houses — the tray under an air cooler, a plant pot saucer, a discarded tyre, a bucket on a roof, an uncovered overhead tank, even a bottle cap. It does not breed in sewers. This is why dengue control is a household job rather than a municipal one, and why it follows the monsoon: in Punjab the runs from about late August into November, with cases falling away when night temperatures drop.
How the illness moves
Dengue does not follow the pattern of most fevers, and understanding its three phases is the single most useful thing a patient or a family member can know. Symptoms begin four to ten days after the mosquito bite.
| Phase | When | What happens | What to watch |
|---|---|---|---|
| Febrile | Days 1-3 | Sudden high fever, severe headache and pain behind the eyes, aching muscles and joints, nausea, a flushed face | Keep fluids going. Paracetamol only. Get a blood count and an NS1 test |
| Critical | Days 3-7, as the fever falls | Fluid can leak out of the small blood vessels. The count falls and the packed cell volume rises. Most people pass through this without trouble; a minority go into shock | This is the window. Any warning sign means hospital immediately. Daily blood counts. Do not relax because the fever has gone |
| Recovery | Days 7-10, sometimes longer | Leaked fluid returns to the circulation, appetite comes back, and a characteristic itchy rash often appears on the hands and feet as the skin recovers | Too much intravenous fluid at this stage can overload the circulation, so drips are reduced. Exhaustion lasting two to four weeks is normal |
The symptoms
- Fever, sudden and high, often 39 to 40 degrees Celsius, with shivering.
- Headache, severe, and pain behind the eyes that is worse on moving them.
- Muscle and joint pain severe enough to earn dengue its old name of break-bone fever.
- Nausea, vomiting and loss of appetite, often with a metallic taste.
- Rash. A flushed face and neck in the first days, then from about day three a widespread red rash, and in recovery an itchy blotchy rash with pale islands, classically on the palms and soles.
- Minor bleeding. Bleeding gums when brushing, a nosebleed, or pinpoint red spots in the skin that do not blanch when pressed.
- Extreme tiredness, which outlasts the fever by weeks.
Not everyone gets all of these, and a mild dengue infection can look like any other viral fever. In the season, in an area with cases, a fever with a severe headache and body aches should be treated as possible dengue until a blood test says otherwise.
How it is diagnosed
- NS1 antigen detects a viral protein and is the test to ask for in the first five days of fever. A positive NS1 confirms dengue. A negative one late in the illness does not exclude it.
- IgM antibody becomes positive from about day five onwards. Ordering it on day two is a common and wasted expense.
- , repeated daily from about day three. Two numbers matter: the count, which falls, and the haematocrit or packed cell volume, which rises when plasma is leaking. A rising haematocrit with a falling platelet count is the combination that signals the critical phase, and it is more informative than either number alone.
- , which is typically low in dengue and helps distinguish it from a bacterial infection.
- , because dengue commonly inflames the liver, which changes what painkillers are safe and occasionally causes .
- of the abdomen and chest, looking for free fluid around the gallbladder, in the abdomen or around the lungs — direct evidence of plasma leak.
Platelets: what the number does and does not mean
Almost every conversation about dengue in Pakistan becomes a conversation about platelets, and much of it is wrong. are the cell fragments that plug small leaks in blood vessels. In dengue the count falls, usually reaching its lowest point around days five to seven, and then recovers on its own over two to three days without anything being done to it.
The count is a marker of where you are in the illness. It is not, by itself, what makes dengue dangerous. The plasma leak is, and the leak is measured by the haematocrit, the blood pressure, the pulse and the urine output — not by the platelet number. A person with a platelet count of 40,000 who is drinking, passing urine and warm to touch is in far better shape than a person with 90,000 who is vomiting, restless and cold.
| Count (per microlitre) | What it means | What is usually done |
|---|---|---|
| Above 150,000 | Normal range | Routine care, daily count during the critical phase |
| 100,000-150,000 | A mild fall. Extremely common in dengue | Fluids, paracetamol, a daily blood count, and the warning signs explained to the family |
| 50,000-100,000 | A moderate fall, still expected | Counts once or twice daily. No injections into muscle, no , soft toothbrush. Admission if any warning sign appears |
| 20,000-50,000 | A marked fall | Usually admitted for observation. Bleeding precautions. Still no automatic transfusion |
| Below 20,000 | A severe fall | Inpatient care. Transfusion is considered for significant active bleeding, or where a doctor judges bleeding risk high — a low number on its own is not an indication |
Fluids: the treatment that actually works
There is no medicine that kills the dengue virus. What saves lives is preventing by replacing fluid at the right rate at the right time, and most of that can be done by mouth at home in the febrile phase.
- is the best choice, because dengue loses salt as well as water. Ordinary water alone, in large amounts, is not as good.
- Also useful: rice water, thin daal water, clear soups, fresh lime with a pinch of salt and some sugar, yakhni, coconut water, and milk if it is tolerated.
- Avoid dark red, brown or purple drinks. If vomiting starts, no one can tell whether the colour is the drink or blood. This is standard WHO advice and it is genuinely practical.
- Judge by urine, not by volume drunk. Passing a reasonable amount of pale urine at least every four to six hours means the fluid is enough. Small amounts of dark urine, or none for six hours, is a warning sign.
- Small amounts, often, beats large amounts occasionally, especially when there is nausea.
- Intravenous fluid is for hospital: in the critical phase the right rate changes hour by hour, and both too little and too much do harm. A drip set up at home or in a small clinic without monitoring is not a safe substitute for admission.
Fever and pain: paracetamol, and nothing else
Paracetamol is the only that is safe in dengue. For an adult the usual dose is 500 mg to 1 g every six hours, with a ceiling of 4 g in twenty-four hours — and less if you weigh under 50 kg, drink alcohol, or have been told your liver tests are abnormal, which is common in dengue. For a child the usual dose is 10 to 15 mg per kilogram per dose, up to four doses in a day. Check the label of every product you take: many combination cold remedies contain paracetamol and it is easy to double up without realising.
The remedies that circulate every season
Every dengue season brings the same list: papaya leaf juice, goat milk, kiwi fruit, dragon fruit, wheatgrass, and a range of packaged tonics sold with a platelet claim on the label. It is worth being direct about these, because a family being told to find them at midnight is a family not going to hospital.
- Papaya leaf extract has been studied in small trials, mostly of low quality, and some report a faster rise in platelet count. None has shown that it reduces bleeding, shortens hospital stay, or saves lives — which are the outcomes that matter. It commonly causes nausea and vomiting, which is the last thing a dengue patient needs. It is not in the WHO guidance or in any national dengue protocol.
- Goat milk, kiwi, dragon fruit and wheatgrass have no evidence behind them at all in dengue.
- The real harm is time and attention. The critical phase is a window of a few hours in which fluid and monitoring change the outcome. Spending those hours sourcing a remedy, or feeling reassured because one has been taken, is how a treatable case becomes a severe one.
- If a family wants to give papaya leaf juice alongside proper fluids, monitoring and hospital care, it is unlikely to do direct harm beyond the vomiting. It must never replace any of those three.
Getting dengue twice
Recovering from one serotype protects against that serotype for life, and against the others for only a few months. A later infection with a different serotype carries a higher risk of severe dengue, because the antibodies from the first infection can help the second virus enter cells rather than neutralising it. In practice this means a person who has had dengue before should treat a new dengue fever with more caution, not less, and should have a blood count from day three rather than waiting.
Two dengue vaccines exist and are used in a small number of countries under specific conditions — one of them only in people who have already had dengue once. Neither is part of routine immunisation in Pakistan. Mosquito control remains the only prevention available here.
Stopping it at home
- Empty and scrub, weekly. The eggs stick to the sides of a container and survive drying, so tipping the water out is not enough — the sides need wiping. Cooler trays, plant pot saucers, buckets, bird baths, water for animals, the tray under a fridge.
- Cover every water store. Overhead tanks, underground tanks, drums and buckets with a tight lid or a fine mesh.
- Clear the roof and the yard. Tyres, broken pots, plastic sheeting, unused sinks and construction debris hold water after rain.
- Repellent in the daytime. Aedes bites in daylight, so a mosquito net at night protects only partly. Use repellent on exposed skin and wear long sleeves and full trousers, particularly at dawn and dusk.
- Screens on windows, and an insecticide spray in dark corners and under furniture where the mosquito rests.
- Protect the patient too. A person with dengue who is bitten passes the virus to the next mosquito. Someone with dengue should sleep under a net during the day as well as at night, for the household's sake.
When to see a doctor
See a doctor within the first two days of any fever during the dengue season, particularly if there are cases nearby, and ask for an NS1 test and a blood count. Do not wait for a rash and do not wait for the fever to break.
Have the blood count repeated daily from day three to day seven. Arrange for someone to stay with the patient through that window, and make sure that person knows the warning signs by heart. Go to hospital the moment one appears. Certain groups should be seen early and have a lower threshold for admission at any stage: infants, adults over 60, pregnant women, and anyone with , kidney disease, heart failure, a bleeding disorder, or who takes a blood thinner.
Common questions
Still not sure what to do?
Reading about a symptom only goes so far. A doctor who can ask you questions and examine you will get further in ten minutes than any article can.
