Malaria: Beware of Mosquitoes!

September 6th, 2011

By Marielle Bibeau, physician, International Traveller’s Clinic

Were you aware that malaria is the deadliest infectious disease among travellers? Every year, 500 million people are infected with malaria. One to three million among them will die. Nonetheless, it is possible to prevent this extremely dangerous disease by making sure that you are aware of its causes, the persons who are at greater risk, its symptoms, and preventive measures.

What causes malaria?

Malaria is caused by the Plasmodium parasite, which is transmitted by the bite of infected mosquitoes. They normally bite between sunset and sunrise.

Who are at greater risk?

Infants and pregnant women are at greatest risk of suffering from malaria. Immigrants from southern countries in which malaria is present also need to be monitored. They are less protected against the disease when they return to their home countries. Travellers suffering from specific medical conditions may also have more problems.

What are the symptoms of malaria?

Malaria is usually expressed by the onset of fever and flu-like symptoms - chills, headache, and muscle pain. Those infected may also experience digestive problems, including nausea, vomiting and diarrhea.

Plasmodium falciparum infections are the most severe cases. Such an infection may be deadly within a few days if left untreated.

Consult your physician if you have a fever when travelling or after you have returned from a journey abroad.

How can I protect myself?

Most malaria infections and deaths are avoidable if travellers follow the standard recommendations when abroad. Taking certain precautions against mosquitoes can help to prevent malaria:

  • Apply insect repellent containing 20 to 35 percent DEET (i.e., Watkins).
  • Wear light-coloured long-sleeved shirts and long pants.
  • Do not wear fragrances.
  • Use a deltamethrin-impregnated bed net or sleep in an air-conditioned room with screened windows.

Preventive medications are also available to ward off malaria; however, none are 100% effective. Be cautious and follow the mode of administration.

  • Any intolerance to an antimalarial drug should be reported to your physician so that he can write you another prescription.
  • Avoid purchasing medications in tropical countries: counterfeiting is not uncommon.

What should you do if you have fever?

Consult! Any bout of fever in a malarial zone or after returning from such an area should be considered an episode of malaria until diagnosed otherwise. A blood test will confirm the diagnosis. Medications are prescribed if the test result is positive. If you have suffered from malaria while abroad, it is important to consult your physician for a further evaluation once you have returned from your journey.

For further information, consult the CSSS-IUGS International Traveller's Clinic, located at CLSC 1200 King Street East, 819 564-5160, or visit

Sources :

Guide d’intervention en Santé-voyage 2010 (INSPQ)
Agence de la Santé publique du Canada 2009

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