Different types of dengue: what to know

The dengue virus has four recognised serotypes. A person can be infected more than once because protection after one infection does not reliably protect against every other serotype. The serotype cannot be identified from symptoms alone; laboratory testing may be needed.

Clinicians also describe dengue by how serious the illness is. Mild dengue may cause fever, headache, pain behind the eyes, muscle or joint aches, nausea, or a rash. Dengue with warning signs can worsen around the time the fever settles. Severe dengue may affect circulation, breathing, or organs and needs urgent hospital treatment. The labels describe the illness at that time, so monitoring matters even when the first symptoms seem manageable.

Arrange a medical assessment if you have a fever after living in or travelling to an area where dengue occurs, especially with intense headache, muscle aches, joint pain, chills, or unusual bruising. Rest, drink fluids regularly if you can, and record your temperature and symptoms. Use only fever medicine recommended by a clinician or pharmacist; avoid aspirin and ibuprofen unless a clinician specifically tells you to take them, because they can increase bleeding risk. Prevent mosquito bites while ill so mosquitoes are less likely to spread the virus to others.

Seek urgent medical help for severe abdominal pain, persistent vomiting, bleeding from the nose or gums, blood in vomit or stool, difficulty breathing, fainting, confusion, extreme sleepiness, cold or clammy skin, or very little urine. Warning signs can appear as the fever improves, so do not assume that a lower temperature means the danger has passed. A child, pregnant person, older adult, or anyone with a significant long-term condition may need prompt advice even with less dramatic symptoms.

Ask which tests are appropriate and when they should be done, whether your symptoms include warning signs, how much fluid to drink, which medicines are suitable, and what changes should prompt urgent review. Tell the clinician when the fever began, where you have travelled, any previous dengue infection, and all medicines you take.