Quick answer. Dengue is a mosquito-borne viral infection spread by the Aedes mosquito and is endemic in Singapore year-round. Symptoms usually appear 4-7 days after a bite: sudden high fever (2-7 days), severe headache with pain behind the eyes, muscle and joint aches, rash, and easy bruising or bleeding. There is no specific antiviral cure, so treatment is supportive: rest, fluids and paracetamol for fever. Avoid ibuprofen and aspirin, which raise bleeding risk. Watch for warning signs like severe abdominal pain, persistent vomiting, bleeding or lethargy, which often start as the fever drops, and go to A&E immediately.
Dengue fever is one of the most common acute infections in Singapore and circulates throughout the year, with case numbers tracked weekly by the National Environment Agency (NEA). It is caused by the dengue virus and spread by the Aedes mosquito, which breeds in clean, stagnant water around homes.
Most people recover with rest and fluids, but a small number develop severe dengue, which can be life-threatening. Knowing the warning signs and when to seek emergency care is the most important part of managing dengue safely.
At a glance
| Feature | Common dengue symptoms | Warning signs (go to A&E) |
|---|---|---|
| Fever | Sudden high fever for 2-7 days | Fever subsiding but feeling worse, not better |
| Pain | Headache, pain behind the eyes, muscle and joint aches | Severe or persistent abdominal pain or tenderness |
| Gut | Mild nausea, reduced appetite | Persistent vomiting; black or bloody stools |
| Bleeding | Mild gum/nose bleeding, easy bruising | Heavy bleeding, blood in vomit or urine |
| Behaviour | Tiredness, feeling unwell | Drowsiness, restlessness, lethargy or confusion |
Symptoms and how dengue progresses
Symptoms typically develop 4 to 7 days after an infected mosquito bite. Classic features include:
- Sudden onset of high fever lasting 2-7 days
- Severe headache, often with pain behind the eyes (retro-orbital pain)
- Muscle and joint aches
- Skin rash
- Nausea and vomiting
- Mild bleeding such as nose or gum bleeding, or easy bruising
A dangerous phase can begin as the fever starts to come down (around day 3-7). This is exactly when warning signs of severe dengue may appear, so do not assume you are recovering just because the fever has dropped.
Warning signs: when to go to A&E
Severe dengue is a medical emergency. Go to the nearest A&E immediately if you or your child develop any of these warning signs, which often start 1-2 days after the fever subsides:
- Severe or persistent abdominal pain or tenderness
- Persistent vomiting
- Bleeding: gum or nose bleeding, black stools, or blood in vomit or stool
- Restlessness, drowsiness or lethargy
- Cold, clammy skin, pale appearance or feeling faint
Infants, older adults, pregnant women and people with chronic conditions are at higher risk and should seek care early.
Treatment: supportive care, not antibiotics
There is no specific antiviral treatment for dengue, and antibiotics do not work against viruses. Care is supportive and focuses on:
- Rest and staying well hydrated (water, oral rehydration salts, soups)
- Paracetamol for fever and pain
- Avoiding ibuprofen, other NSAIDs and aspirin, as these can increase bleeding risk
Your doctor may arrange blood tests to monitor your platelet count and haematocrit. A low or falling platelet count, signs of fluid leakage, or warning signs may mean you need hospital admission for monitoring, intravenous fluids or, rarely, blood transfusion.
The Aedes mosquito and Singapore's dengue situation
Dengue is spread by the Aedes aegypti mosquito (with Aedes albopictus as a secondary vector), which bites mainly during the day and breeds in clean stagnant water as small as a 20-cent coin. All four dengue serotypes (DENV-1 to DENV-4) circulate in Singapore, and the predominant type shifts over time.
NEA publishes weekly dengue case numbers and active cluster maps and runs control measures including inspections, fogging and Project Wolbachia, which releases male Wolbachia-carrying Aedes aegypti to suppress the mosquito population. A field study published in 2024 reported over 70% lower dengue risk in release areas. Check NEA’s dengue page to see if you live in or near an active cluster.
Vaccines: Dengvaxia and Qdenga status
Dengvaxia is registered with the Health Sciences Authority (HSA) in Singapore for individuals aged 12 to 45 years, given as three doses. It works best in people who have had a previous dengue infection and is generally not recommended for those who have never had dengue, as it may increase the risk of severe disease in that group. Pre-vaccination testing and a discussion with your doctor are important.
Qdenga (TAK-003) is approved in several other countries, but as of 2026 it is best to check directly with HSA or your doctor for its current registration status in Singapore. Vaccination is not a substitute for mosquito-bite prevention.
Prevention: Mozzie Wipeout and bite protection
Reduce breeding around your home using NEA’s B-L-O-C-K steps at least weekly:
- Break up hardened soil in plant pots
- Lift and empty flowerpot plates
- Overturn pails and wipe their rims
- Change water in vases and flower pots
- Keep roof gutters clear and add BTI insecticide
Protect yourself from bites with repellents containing DEET, picaridin or IR3535, reapplied as directed, and by wearing long, covering clothing. If you have dengue, continuing to prevent bites helps stop you passing the virus on to others.
Recovering safely at home
If your doctor advises home care, the priority is rest, steady hydration and close watching for warning signs. Drink water, oral rehydration salts, soups or juices regularly, and take paracetamol for fever and pain. Do not take ibuprofen, other anti-inflammatories or aspirin, as these raise the risk of bleeding. Keep your scheduled blood tests, because platelet counts can fall during recovery. Remember that the most dangerous phase often begins as the fever drops, so do not assume you are in the clear simply because you feel cooler.
How to prepare for a clinic or A&E visit
- Note when your fever started and track your temperature and fluid intake.
- Bring a list of medicines, existing conditions and whether you are pregnant.
- Tell the doctor if you live in or near an active dengue cluster.
- Go straight to A&E if warning signs appear, rather than waiting for an appointment.
Special situations
Infants, older adults, pregnant women and people with chronic conditions are at higher risk of severe dengue and should seek care earlier. A second dengue infection with a different serotype can be more severe, so do not assume a milder course just because you have had dengue before.
Common questions
Can I catch dengue more than once?
Yes. There are four dengue serotypes, and infection with one gives lasting protection only against that type, so reinfection with another is possible.
Why avoid ibuprofen and aspirin?
They can increase the risk of bleeding and stomach irritation, which is particularly unsafe in dengue. Paracetamol is the preferred option for fever and pain.
Related guides
- Best GP & Family Clinics in Singapore — our editorial shortlist
- GP & family clinics directory
- Hand, foot & mouth disease
- Influenza (flu)
- Shingles (herpes zoster)
Sources
- HealthHub (MOH) – Dengue Fever
- SingHealth – Dengue Fever (symptoms, warning signs, treatment)
- NEA – Dengue Cases (weekly situation, clusters, B-L-O-C-K)
- NEA – Project Wolbachia (Wolbachia-Aedes Suppression Strategy)
- HSA – HSA Approves Dengvaxia Vaccine
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