What should you know about pernicious malaria?

Severe malaria is caused by malaria parasites carried by infected mosquitoes. The infection can begin with fever, chills, sweating, headache, or muscle aches, but serious illness may involve confusion, extreme weakness, breathing difficulty, jaundice, seizures, or collapse. Symptoms can appear after returning from a malaria-risk area, and the illness may not follow a predictable pattern.

A travel history is essential. A blood test can look for malaria parasites, but an early result may not settle the question if symptoms continue. Clinicians may arrange repeat testing and assess blood counts, glucose, kidney function, and other signs of severe illness.

If fever or flu-like illness develops during travel or after return from a malaria-risk area, seek medical care urgently and state the countries visited, travel dates, mosquito bites, prevention medicines, and previous malaria history. Do not rely on medicines left from an earlier trip or delay care while waiting for symptoms to follow a pattern. Treatment depends on the parasite, severity, pregnancy status, and local resistance patterns, so it must be prescribed.

For future travel, arrange a travel-health consultation early enough to discuss malaria prophylaxis, bite prevention, accommodation, and an emergency plan.

Go to emergency care immediately for confusion, fainting, seizures, severe weakness, difficulty breathing, persistent vomiting, inability to drink, yellowing of the skin, dark urine, or rapidly worsening fever. A child, pregnant person, older adult, or person with reduced immunity should be assessed promptly for any fever after possible exposure.

Ask which tests are needed and whether they should be repeated, what warning signs to watch for, which treatment is being considered, and when it is safe to return to normal activity. For travel, ask which prevention plan fits the destination and your medicines or health conditions.