Science News

Zika virus Public Health Emergency

Mon, 8th Feb 2016

Chris Smith

A public health emergency has been declared this week by The World Health Organisation around the outbreak of Zika virus in Brazil, where as many as a million people may have been infected since last year.

Zika was first described - and named after - the Zika forest in Uganda, Africa, in 1947 where it was found in monkeys. But with the exception of sporadic human cases in the 1950s, the agent maintained a low profile. Aedes aegypti in Dar es Salaam, Tanzania

Infected individuals were rarely symptomatic, and those that were had a fleeting rash, fever, headache and sore eyes and usually an uneventful recovery.

Zika appears to have spread indolently across Asia in the 1970s, borne by the Aedes aegypti mosquito that acts as a vector for the disease.

The range of the Aedes mosquito has been expanding in parallel with urbanisation. These mosquitoes are active in the daytime and prefer to bite large animals, like humans.

They are also attracted to towns and cities owing to breeding opportunities presented by nearby rubbish tips and detritus, like old tyres, which often provide pools of stagnant water.

By 2007 Zika had made it as far as the Pacific island of Yap where it caused a relatively inconsequential outbreak, but since then levels of activity have been low. But last year it began to spread rapidly across South and Central America. Some have speculated that the World Cup in 2014 may account for the arrival of the agent in Brazil, and other possible culprits include a competitors in a rowing competition who hailed from a Pacific island.

But what is worrying health officials is the association between the sudden uptick in Zika cases and increased reports of cases of infants born with microcephaly, a condition characterised by an abnormally small brain.

Since October 2015, the country has recorded 4000 such cases. At least a proportion of these appear to tally with histories from affected mothers of their having succumbed to a rash-like illness early in their pregnancy.

The genetic material has also been recovered from the brains or the amniotic fluid of some affected cases. Although Aedes mosquitoes appear to be the main carriage vector for the virus, a further case report has been released this week suggesting that Zika may also be able to spread sexually.

The partner of a US man who had returned recently from Venezuela succumbed to the infection. Tests showed blood in the man's semen, suggesting that this was the likely route for viral transmission.

Unanswered questions currently include how long a person remains infectious in this way after they recover from the disease.

Also, some infectious disease specialists are warning that microcephaly in babies born to women infected during pregnancy might represent only the more severe end of a spectrum of problems that awaits these infants as they grow up.

"It might be like rubella, or CMV," says Oxford's Peter Horby, "where there can be problems in other parts of the body too, and we don't know about those yet."

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Seems like a scam and an outrageous coverup to me.

The recent incidence of microcephaly in Brazil is about 100 times greater than the reported number of cases associated with Zika infection. The real problem seems to stem from the government-mandated vaccination of pregnant women, an off-label use of a vaccine designed and licensed elsewere for 10 - 12 year-old kids only. Why 10 to 12? Presumably because it could harm younger kids and in the opinion of the manufacturers and the FDA, should not be administered where there is a likelihood of the  recipient being pregnant. 

Zika infection is generally considered fairly insignificant and is by no means new.

So the question is who was bribed into mandating it, and whether any official heads will roll (of course not!). Not a medical problem, just another job for the accountants and police to investigate and the politicians to sweep under the carpet. alancalverd, Mon, 8th Feb 2016

The vaccine in question is known as Tdap.

"Towards the end of 2014 Brazil mandated a Tdap vaccination for all pregnant women. The vaccine is made by GlaxoSmithKline in the UK and is called, “Boostrix”. Despite the fact that the safety of Boostrix in pregnant women has not been studied, despite the fact that the only study (one) was done on pregnant rats (according to their own reports), Boostrix became a required vaccination in Brazil. The recommended time for the dosage is between the 27th and 36th week of pregnancy."

A class C drug (antidepressant). Taking antidepressants during pregnancy led to ‘delayed fetal head growth’, according to a study.

"To make matters stickier, in 2015 The Bill and Melinda Gates Foundation donated over $300,000 to the Vanderbilt Vaccine Research Program to study the immunicological effects of Tdap on pregnant women."

"Maternal use of selective serotonin reuptake inhibitors, fetal growth, and risk of adverse birth outcomes."

tkadm30, Tue, 9th Feb 2016

Entirely sensible (though always a hell of a difficult ethical problem) to study the effect, utterly criminal to mandate its use without such testing. alancalverd, Tue, 9th Feb 2016

That's funny. Doctors in the US have been recommending prenatal TDAP vaccination since 2011 (after reviewing data indicating no relationship to birth defects)

Where are all the malformed TDAP babies in the US? (HINT: there aren't any)

It's also odd that microcephaly can be diagnosed several weeks BEFORE the scheduled immunization, leading to an interesting interpretation of causality...

I should also note that identifying intended recipients as 10-12 years of age is also misleading at best. In the US, infants get TDAP boosters at 2, 4, 6 and 15 months, and then again as preteens.

Time will tell what is actually going on in Brazil, but I don't think blaming vaccination is at all reasonable at this stage. chiralSPO, Tue, 9th Feb 2016

But vaccines are not ssris...

Drinking alcohol also leads to microcephaly, but no one (credible) claims that marijuana leads to these same defects. One must be very careful when drawing analogies between drugs that act on different pathways. chiralSPO, Tue, 9th Feb 2016

I believe this is incorrect... The FDA classified the Tdap vaccine as a antidepressant:

"The CDC recommendation for Tdap initially came as whooping cough cases rose with over 2700 in the US in 2011. Not exactly an epidemic statistic! The FDA classified the Tdap vaccine as a Class C Drug – “Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.”"

tkadm30, Tue, 9th Feb 2016

Worth reading that report very carefully. The number of women vaccinated whilst pregnant was very small (unsurprising since Tdap is not licensed for such use in the USA or indeed anywhere) and the report only discusses effects on the women. And there's a heck of  difference between a hypothetical recommendation based on a priori risk assessment, itself based on trials of selected parts (tetanus and diphtheria) of the Tdap cocktail, and the results of an actual experiment including pertussis. Think thalidomide. alancalverd, Thu, 11th Feb 2016 contains some interesting information, e.g.

alancalverd, Thu, 11th Feb 2016

Zika is common in many countries now, including Columbia and Venezuela. A rise in prevalence of Guillain-Barre Syndrome appears to be associated with this, in Brazil as elsewhere. Yet the microcephaly outbreak only occurred in Brazil. A recent study on the effects of the MMR vaccination campaign in Brazil (Soares et al) found that a small proportion of women unknowingly in early pregnancy had been accidentally given the MMR vaccine (no adverse effects were recorded,including microcephaly associated with rubella infection), so accidental vaccination can and does occur there. Microcephaly is initiated in the early weeks of pregnancy - later challenges will not cause it to occur. In South America, only Brazil has the mandatory Boostrix TDAP vaccination (Boostrix) programme - it is not used in this way in either Colombia or Venzuela. The Boostrix program started in late 2013/early 2014. The first excess of microcephaly cases was reported seven to eight months later. Join up the dots! (see my comments at Doug Cross, Fri, 4th Mar 2016

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