Saturday, April 16, 2016

New Zika research: It just keeps getting worse

Hawai`i continues to be on the alert for Zika virus, and there are increasing good reasons for concern.

Here are some updates on Zika virus.

The Centers for Disease Control and Prevention have confirmed the link between the mosquito-borne disease and babies born with shrunken heads, a condition called microcephaly.

Here’s the ScienceDaily piece on that. 

 The report from CDC was published in the New England Journal of Medicine under the title,  “Zika Virus and Birth Defects — Reviewing the Evidence for Causality.” The original paper is here.

There’s a caveat here. This isn’t original research, but a review of the original research done by others, and it concludes that, considered as a whole, the connection is inescapable. 

Here is the language they used: “we evaluated available data using criteria that have been proposed for the assessment of potential teratogens. On the basis of this review, we conclude that a causal relationship exists between prenatal Zika virus infection and microcephaly and other serious brain anomalies.”

In adults, Zika has been associated with a neurological disease called Guillain-Barre Syndrome. Now, another new paper suggests that adults with Zika are also at risk for a rare autoimmune disorder, acute disseminated encephalomyelitis.

The connection between Zika and this brain disease is still not entirely locked up. Brazilian researchers found 151 cases of brain disorders among Zika patients. Only a very few came down with acute disseminated encephalomyelitis. 

The paper on this was presented this week to the conference of the the American Academy of Neurology. The ScienceDaily story on it is here. 

It is, once again, not a smoking gun, but there are reasons for concern, and there are worries about why and how Zika attacks the brain. 

“Clinicians should be vigilant for the possible occurrence of (acute disseminated encephalomyelitis) and other immune-mediated illnesses of the central nervous system," said James Sejvar, with the Centers for Disease Control and Prevention.

There have been suggestions that Zika may not only be transmitted by mosquito, but that it might be spread directly between humans through sexual activity. A new French study, reported in the New England Journal of Medicine and here on EurekAlert,  confirms it.

"Their analyses have shown 100% genetic correlation between the form of the virus present in a man who contracted the virus in Brazil and that of a woman who had never travelled in the epidemic area, but who had sexual relations with him," the EurekAlert article said.

Oh, and here's an interesting piece, also in ScienceDaily, about a new mosquito trap, developed by Canadian and Mexican researchers, that may help reduce the populations of the Aedes mosquitoes that carry Zika.

See RaisingIslands’ previous posts on Zika here.

© Jan TenBruggencate 2016

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