Zika virus spreading 'explosively,' WHO warns
CTVNews.ca Staff, Published Thursday, January 28, 2016 7:41AM EST, Last Updated Thursday, January 28, 2016 11:21AM EST, http://www.ctvnews.ca/health/z...-who-warns-1.2755434
CTV News Channel: 3 Canadians infected with Zika
With concerns that the Zika virus is “spreading explosively,” the World Health Organization is convening an emergency committee on Monday to decide if the outbreak should be declared an international health emergency.
In a statement Thursday morning, WHO Director-General Dr. Margaret Chan said there is an “extremely high” level of concern about the virus, which may be linked to a serious birth defect and neurological problems in some parts of South America.
“Questions abound. We need to get some answers quickly,” she said.
Although there is still no proof that Zika is responsible for a sudden spike in the number of babies being born in Brazil with abnormally small heads – a condition called microcephaly -- a causal relationship between the virus and birth defects “is strongly suspected,” the WHO statement said.
“The possible links, only recently suspected, have rapidly changed the risk profile of Zika, from a mild threat to one of alarming proportions,” Chan said.
“The increased incidence of microcephaly is particularly alarming, as it places a heart-breaking burden on families and communities.”
The virus is also being linked to an increase in cases of Guillain-Barre syndrome, a condition in which the body’s immune system attacks the nervous system.
The Zika virus has spread to more than 20 countries in the Americas in the last year. It is transmitted by a species of daytime mosquito called Aedes aegypti. Earlier this week, the WHO said the virus is likely to spread to every country in the Americas, except Canada and continental Chile.
Dr. Chan said Thursday it is concerned about the lack of immunity in the newly affected areas in the Americas, as well as the absence of a vaccine, any specific treatments, or any rapid diagnostic tests.
“For all these reasons, I have decided to convene an Emergency Committee under the International Health Regulations,” she said, adding that the committee would meet in Geneva.
“I am asking the committee for advice on the appropriate level of international concern and for recommended measures that should be undertaken in affected countries and elsewhere. I will also ask the Committee to prioritize areas where research is most urgently needed.”
Millions of asymptomatic cases
In a conference call with journalists Thursday, Sylvain Aldighieri, head of WHO's epidemic response team in the Americas, said there could be as many as 3 to 4 million cases of Zika in the Americas over the next year.
He said that estimate was based on the previous spread of dengue fever, which is also carried by the same mosquito species.
But Aldighieri noted that the vast majority of those cases will be asymptomatic, meaning they won’t show the typical rash and fever that Zika infection can cause in 20 per cent or patients. This "silent circulation" of the disease may make tracking the virus’ spread more difficult, he said.
Dr. Bruce Aylward, who runs WHO's outbreaks and health emergencies department, noted in the conference call that there is a lot of uncertainty on these estimates which are likely to change as more is learned about the virus and its spread.
He added that WHO is working with both the global scientific community and industry leaders to help develop a Zika virus test, treatments and perhaps a vaccine. He added that Monday’s emergency meeting will also look to prevent “inappropriate” travel or trade bans.
As for where it will spread next, Aylward says any countries that already have dengue fever should be on the lookout for Zika infections.
Earlier on CTV’s Canada AM, Dr. Vanessa Allen, the chief of microbiology with Public Health Ontario, said she felt the concern about the Zika virus was justified.
“It’s new because it’s in a population that has never been exposed to this virus. A lot of people are getting sick and I think it’s appropriate for us to mobilize in this case. I think there’s a lot still to be learned about the virus,” she said.
Allen said her hope is that the wealth of knowledge around the world can be mobilized to begin working on ways to protect people from the virus. That could include the development of a vaccine, although she warned that would take years.
“Usually, it takes at least 10 years for a vaccine to be developed and fully checked to make sure it’s safe for production,” she said.
That process could be expedited the way it was for the Ebola virus, she said. In that case, a vaccine went to the human trials stage much faster than normal. But she said a vaccine is likely a long way off, even in the best-case scenario.
“Certainly, it would not be in the phase of several months; it would be several years,” Allen said.
She added that other tools to fight the virus could be developed in the meantime. They could include better diagnostic tests and perhaps targeted Zika treatments, as none currently exist.
With files from The Associated Press28, 2016.
China's Margaret Chan, General Director of the World Health Organization, WHO, speaks about the Information Session on Zika virus for WHO Member States, during a WHO Executive Board session, at the World Health Organization (WHO) headquarters in Geneva, Switzerland, Thursday, Jan. 28, 2016. (Martial Trezzini/Keystone via AP)
An Aedes aegypti mosquito is photographed through a microscope at the Fiocruz institute in Recife, Pernambuco state, Brazil on Jan. 27, 2016.(Felipe Dana / AP Photo)