Pregnant women heading south being warned of Zika virus

[Virus linked to birth defects prompts U.S. Centers for Disease Control and Prevention to advise expecting mothers not to travel to certain Latin American countries/CBS NEWS]

Pregnant women with plans to travel south this winter are being urged to protect themselves from a mosquito-borne virus that — while mild for adults — may be the cause of serious brain defects in babies and has prompted travel warnings from U.S. and Canadian public health agencies.

The Zika virus, spread by subtropical Aedes mosquitoes, is native to parts of Asia and Africa and is now found in a number of Latin American and Caribbean countries. Among them, Mexico, Brazil and Puerto Rico have reported locally acquired cases of the Zika virus, including up to an estimated 1.3 million suspected cases in Brazil last year.

“We are acutely aware of the potential association between the Zika virus infection during pregnancy and the possibility of having birth defects, specifically the microcephaly that’s been seen in Brazil,” said Dr. Isaac Bogoch, an infectious disease researcher at the University of Toronto involved in studies on the virus. “Women who are pregnant or are thinking about getting pregnant need to take an abundance of caution if they are going to travel to areas affected by Zika virus or may be affected by Zika virus.”

Last Thursday, Canadian researchers, including Dr. Bogoch, working in collaboration with researchers from Oxford published an analysis of the pathogen’s potential transmission patterns. Their findings suggest that a majority of people in the United States, Argentina and Italy live in areas susceptible to Zika virus outbreaks.

The main concern for researchers and public health officials is the virus’s effect on unborn babies. On Jan. 13 the U.S. Centers for Disease Control and Prevention (CDC) announced that it found evidence that may link the virus to brain defects in babies, in particular microcephaly.

Babies born with microcephaly have underdeveloped heads and brains and often experience developmental issues. The CDC reported finding the Zika virus in the tissues of four Brazilian babies who died shortly before or after their birth, including two with microcephaly. In 2014, Brazil reported 114 cases of babies born with microcephaly. In figures released last week by the Brazilian health ministry, more than 3,500 cases of microcephaly were seen in 2015.

On the heels of this new data, the Public Health Agency of Canada (PHAC) updated its Travel Health Notice on the virus on Jan. 15. While PHAC maintains the risk to Canadians is low, it urges pregnant women to take care in affected countries.

“It is recommended that pregnant women and those considering becoming pregnant discuss their travel plans with their healthcare provider to assess their risk and consider postponing travel to areas where the Zika virus is circulating in the Americas. If travel cannot be postponed then strict mosquito bite prevention measures should be followed to protect themselves against bites.”

The CDC issued similar warnings, though neither agency has yet to officially raise the risk or warning level from 2 (take special precautions) to 3 (avoid non-essential travel).

“Eighty per cent of people who are infected will not have symptoms, and the symptoms people do have are very mild. Fever, headache, muscle pains — it’s a non-specific viral illness. We rely on surveillance systems in many of these countries to see if the virus is present or not. It’s tricky to confirm Zika in an area and it might take time. Everyday there’s another country reporting the virus,” said Bogoch.

“This is what I would consider a pretty important public health issue that has the possibility to affect millions of people living in the Americas, especially women of childbearing age,” he added. “This is going to be a very active area of research moving forward.”

Despite the fact that Canada is unlikely to experience a Zika outbreak due to its cold climate, the risk remains for pregnant women travelling to affected countries. With the epicentre of the latest outbreak in Brazil, the Summer Olympics — scheduled to be held in Rio de Janeiro this year — may pose a serious public health concern.

For those travelling in affected areas, PHAC urges everyone, but in particular pregnant women or women considering becoming pregnant, to protect themselves against the Zika virus by using insect repellent and mosquito nets, wearing protective clothing and ensuring all doors and windows are screened.