Dengue Fever

Add to my Report Print Email

What is it

Dengue fever is a viral disease spread by infected mosquitoes that can cause severe flu-like symptoms. In some cases, it leads to dengue haemorrhagic fever – also known as severe dengue – which can bring about significant internal bleeding and organ failure.1

Who is at risk

Dengue fever cannot be contracted in Canada. All Canadian cases have been diagnosed in travellers bitten by mosquitos where dengue is present, such as urban and semi-urban areas in tropical and subtropical regions. A visitor’s risk increases if they stay for an extended time in these areas.2 Most people infected with dengue virus are able to recover. However, about 2.5% of people who progress to severe dengue and dengue shock syndrome will die.3

What are the symptoms

Infection with the dengue virus can cause severe flu-like symptoms. In some cases, it may lead to severe dengue or dengue shock syndrome, which can be fatal. However, most people infected show no symptoms at all.3

Symptoms that do develop usually appear within three to seven days (and sometimes up to 14 days) after being bitten by an infected mosquito. They generally include:3

  • fever
  • severe headache
  • pain behind the eyes
  • muscle and joint pain
  • a rash

Symptoms of severe dengue and dengue shock syndrome include:3

  • bruising and mild bleeding (such as from the nose or gums)
  • persistent vomiting
  • severe abdominal pain
  • difficulty breathing

How is it spread

The four types of dengue viruses that cause dengue fever are spread to humans through bites from infected mosquitoes, with the highest risk during the day from sunrise to sunset.4

How is it prevented

There is currently no approved vaccine for dengue fever in Canada. Travellers to dengue-prone regions should protect themselves from mosquito bites, whether outside or inside buildings.5

Protections include:

  • covering up in light-coloured, loose fitting, long-sleeved clothes
  • tucking in shirts
  • wearing long pants and shoes or boots (not sandals)
  • taping the cuffs of pants or tucking them in
  • wearing a hat
  • using insect repellent on exposed skin
  • staying in well-screened accommodations
  • sleeping under a mosquito net

How is it treated

There is no specific treatment for dengue fever. But infected patients can recover and control their symptoms with medical care.7

A person who recovers from one of the four types of dengue will have lifelong immunity against that particular type but not against the three others. Immunity from one type can also increase the risk of developing severe dengue if exposed to any of the other types.2

For further information regarding dengue fever, please speak with your healthcare provider.

REFERENCES

  1. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. (2014) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever.html
  2. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. Risks. (2014) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever/risk.html
  3. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. Symptoms. (2014) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever/symptoms.html
  4. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. Causes. (2014) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever/causes.html
  5. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. Prevention. (2016) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever/prevention.html
  6. Government of Canada. Travel. Travel Abroad. Travel Health and Safety. Insect Bite Prevention. (2016) https://travel.gc.ca/travelling/health-safety/insect-bite
  7. Public Health Agency of Canada. Infectious Diseases. Dengue Fever. Treatment. (2014) https://www.canada.ca/en/public-health/services/infectious-diseases/viral-haemorrhagic-fevers/dengue-fever/treatment.html