On Feb. 1, 2016 the World Health Organization (WHO) declared the Zika virus a Public Health Emergency of International Concern. While Zika is not a direct threat to Canada, physicians should be prepared to answer patients’ questions.
Understanding the Zika virus
Zika virus has been reported in Africa and parts of Asia since the 1950s, and in the southwestern Pacific Ocean in 2007. In 2015, Zika virus emerged in South America with widespread outbreaks reported in Brazil and Colombia.
The Zika virus is mainly spread though the bite of an infected mosquito. On rare occasions, the virus has also been transmitted through:
- sexual contact with an infected person
- blood transfusions from infected donors
An infection in a pregnant woman could be transmitted to her baby through the placenta or during delivery.
There has been no reported spread by casual person to person contact.
No vaccine or medications are available to prevent or treat Zika infections.
The Canadian situation
The Public Health Agency of Canada (PHAC) reports that this mosquito is not present in Canada; our environment is considered to be unsuited for their survival, thereby keeping the probability of transmission here low. There have been 55 travel-related cases of Zika in Canada to date and 1 locally acquired case through sexual transmission have been reported in Canada. PHAC updates cases on Thursday of each week.
It is recommended that pregnant women and those considering becoming pregnant discuss their travel plans with their health care provider to assess their risk and consider postponing travel to areas where the Zika virus is circulating in the Americas.
Canadian Blood Services has announced a 21 day waiting period for blood, cord blood, and stem cell donors who have traveled outside Canada, the US, and Europe. Héma-Québec has also implemented the same change.
Contact the office of your provincial/territorial Chief Medical Officer for further information and guidance.
Some Canadian international air carriers require a note from a health care professional before they will consider making changes to a reservation for flights to countries affected by the virus.
Symptoms and health concerns
Zika virus typically presents with mild symptoms. Only 1 in 4 people infected with Zika virus are believed to develop symptoms. It usually takes between 3 to 12 days for symptoms to appear after infection. The disease symptoms are usually mild and last for 2 to 7 days.
The most common symptoms of Zika virus are headache, muscle and joint pain, mild fever, rash, and inflammation of the underside of the eyelid.
Some countries have reported an increase in birth defects in babies of mothers who were infected during pregnancy. These defects include:
- abnormally small heads (microcephaly)
- incomplete brain development
There is scientific consensus that Zika virus is a cause of both microcephaly and Guillain-Barré Syndrome.
To lower the risk of being infected with Zika virus: use insect repellent; cover as much of the body as possible with long, light-coloured clothing; empty, clean or cover containers that can hold water to remove places mosquitoes can breed; and sleep under mosquito nets.
Compiled with information from the PHAC and WHO.