Dengue: symptoms, which tests and when, and when to go to hospital

What dengue is

Dengue is a viral infection spread by the bite of infected mosquitoes, which are active during the day. Many people can be looked after at home, but some become seriously ill, so it is important to talk to a doctor if you suspect it.

Common symptoms

• High fever (it can reach 40°C)
• Severe headache
• Pain behind the eyes
• Muscle and joint pain
• Nausea and vomiting
• Swollen glands
• A skin rash

Which tests, and when

Which dengue test is most useful depends on how many days have passed since your symptoms began, so your doctor decides what to order. In general, tests that look for the virus or its proteins (such as the NS1 antigen test or PCR) are used in the first days of illness, and tests that look for antibodies (IgM and IgG) are used later.

A complete blood count (CBC) shows your platelet count, which doctors follow during dengue. They look at your symptoms and examination too, not one number alone.

Looking after yourself while you see a doctor

• Rest and drink plenty of fluids.
• WHO advises paracetamol for pain and fever, and avoiding ibuprofen and aspirin because they can raise the risk of bleeding.
• Ask your doctor which medicine and how much is right for you.
• Do not delay seeing a doctor, and go to a hospital right away if any warning sign above appears.

Who is at higher risk

• People infected with dengue for the second time are at greater risk of severe dengue.
• Dengue during pregnancy can affect the baby (for example early birth or low birth weight), so a pregnant woman with a fever should see a doctor early.

Preventing dengue at home

• The mosquitoes bite during the day: cover as much skin as you can with clothing.
• Use mosquito repellent that contains DEET, picaridin or IR3535.
• Use a net if you sleep during the day.
• Cover, empty and clean water storage containers every week.
• Remove places around the home where water collects, such as old tyres, flower pots and broken containers.