Zika Virus

DR.PAUL TALKS ABOUT ZIKA VIRUS ON CTV OTTAWA(January, 2016):

UPDATED AUGUST 5, 2016: WE NOW KNOW THAT ZIKA CAN BE TRANSIMTTED SEXUALLY IN THE SPERM. MORE RECENTLY, THE FIRST CASE OF WOMEN TO MAN TRANSMISSION WAS REPORTED IN NEW YORK.

IN ADDITION, CASES HAVE NOW BEEN REPORTED IN FLORIDA, FROM LOCAL MOSQUITOES.  IN FACT AT THE TIME OF THIS UPDATE, THE CDC HAS ISSUED A TRAVEL ADVISORY FOR PREGNANT WOMEN TRAVELLING TO CERTAIN PARTS OF MIAMI, FLORIDA.

The Zika virus, part the Flaviviridae family of viruses, was first seen in Africa and parts of Asia during the 1950’s and in the southwestern Pacific Ocean area in 2007. In 2015 Zika appeared in South America. According to the Public Health Agency of Canada, locally acquired cases have been reported in Brazil, Chile (Easter Island), Colombia, El Salvador, French Guyana, Guatemala, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Suriname and Venezuela.

How do people get infected?

Although we do not fully understand this virus, we know that most people infected got it from the bite of an infected  Aedes species mosquito. The mosquito can then pass the virus to other people by biting them. These mosquitoes are typically found in tropical climates, breed in domestic stagnant pools of water, are daytime biters and feed both indoors and outdoors. We also suspect that pregnant mothers can transfer the virus to their unborn babies and that it may be transmitted sexually and via transfusion. At this point, it seems that this virus can only infect humans and primates.Anyone living in or traveling to an area where Zika virus is found and has not already been infected with Zika virus is at risk for infection, including pregnant women.

Symptoms of Zika infection

About 20% infected with Zika will get sick and for them, the illness is usually mild. In fact, most people may not even realize they have been infected. Symptoms typically begin 2 to 7 days after being bitten by an infected mosquito and commonly include:

  • Fever,
  • Rash,
  • Joint Pain,
  • Conjunctivitis (Red Eyes).

The diagnosis can be confirmed by a specific blood test. Note that once you have been infected by Zika, you are thought to be protected against future infections.

Consequences of Zika infection

Although most people infected with Zika, do not suffer any serious consequences, recent findings in South America have shed light on the possible effects of the virus on unborn babies. In late 2015, a Brazilian health authorities indicated an alarming increase in the incidence of microcephaly (abnormally small head) among newborns born in areas where Zika virus was known to be in circulation.  Microcephaly indicates that the brain has not developed properly during the pregnancy. This can result in possible devastating, long-term intellectual and physical consequences

Prevention and precautions

Currently, there is no medication available that prevents or treats the infection and there is no vaccine. So the approach focuses on avoiding travel to areas with Zika, mosquito control and mosquito bite prevention. Importantly, because of the possible link to microcephaly in babies, travel alerts have been issued for people traveling to regions and certain countries where Zika virus transmission is ongoing: Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Suriname, and Venezuela.More specifically, the CDC recommends special precautions for pregnant women and women trying to become pregnant:

  • Pregnant women in any trimester should consider postponing travel to the areas where Zika virus transmission is ongoing. Pregnant women who do travel to one of these areas should talk to their doctor or other healthcare provider first and strictly follow steps to avoid mosquito bites during the trip.
  • Women trying to become pregnant should consult with their healthcare provider before traveling to these areas and strictly follow steps to prevent mosquito bites during the trip.

What about the risk in North America?

To date in Canada, one case of Zika infection has been confirmed in a person that came from Brazil(known as an imported infection). The only way this individual can transmit the virus is if he/she is bitten by the Aedes species mosquito which then spread the virus by biting others. We know that the Aedes species of mosquito cannot live in our colder climate so there is literally no chance that the virus can be spread in this way in Canada, and most of the Northern USA. However in southern USA(warmer temperatures), where the mosquito can live and survive, transmission is possible. Accordingly, public health authorities are monitoring the situation very closely.