October 3rd 2016; updated on January 9th 2017
Early September, Minister of Health in Colombia declared end of Zika outbreak. With 78.000 suspected /7166 confirmed cases ; 21 microcephalies and 398 Guillain Barré Syndrome (GBS). It means prevalence for microcephaly estimated in a range of 2.7/10.000 to 29/10.000 at the time being. As of today we have 42 microcephalies recorded leading from 2.7/10.000 to 5.9/10.000 for the confirmed cases.
According to data, 7.9% microcephaly cases are linked/caused by Zika virus so far.
According to evidence based medecine, taking into account tested ZIKV + microcephaly cases, we get 17% of the entire microcephaly tested for ZIKV.
Question: if we all agree to say that Zika virus is involved in the immunological process leading to neural defect and microcephaly, we have to cope with other causes (83%) responsible for microcephalies. On a Global Health issue, it appears more and more obvious that studies are required to build a full picture of the root causes tree regarding microcephaly outbreak in South Americas. By comparing Brazil with Colombia, we might discover different paths to follow, especially by studying what happened in NE Brazil.
Colombia recorded a lot of GBS (>398) compared with microcephaly (>21). A interesting paper is just released in J.Autoimmun 2017 by Colombian researchers pointing out the role of Dengue antibodies. Socio-economics factors are also interfering in the process leading to neurological defects.
“All GBS patients were positive for IgG antibodies against both ZIKV and Dengue virus, and 69% were positive for Chikungunya virus.”
Some time ago, CDC and WHO have posted a statement on microcephaly caused by Zika virus. May be they jump the gun?
On Feb.1st 2016, WHO declared PHEIC with regards Zika virus threats and its potential health impacts worldwide; since, we are observing a surprising crisis management of Zika disease overwhelmed by an international political crisis.
- Starting with WHO and the funds raising in order to sponsoring both studies on Zika virus in Vitro and epidemiology surveys in Vivo. More questions raised than answered so far since the arrival of the virus in South America, mid April 2015. The emergence of new neurological diseases in link with the virus like GBS, Myelitis or microcephaly which seem to be related to an autoimmune disease are responsible for fears leading to threats for Public Health/Global Health. Pictures of microcephaly posted in Newspapers and social medias are indecent but attracting to People. “Unfortunately”, Zika is responsible for less fatalities than Ebola and is less bankable, despite a urge need to fight the disease.
- Looking at Brazil, we are focusing on the huge amount of microcephaly cases occurring since April 2015 when the Zika virus arrived for the first time in South America. In a way, Zika is a “good opportunity” to hide some of critical points with regards Politics in Brazil including but not limited to corruption scandal with Petrobras, Impeachment procedure of Mrs President. But here are other corps in the cupboard, I mean socio-economics or environmental issues: lack of potable/drinkable water pipe system, sanitation, waste management, vector control by using toxic pesticide/larvicide, poverty leading to malnutrition. It is surprising noticing that the country where started in 1992 in Rio, The precautionary principle applied to Sustainable Development, poor Public Health policy is implemented in some areas like in NE Brazil for testing and monitoring whenever an infectious disease outbreak is emerging. No doubt that budgets have been absorbed by the Olympics Games this summer.
- What is going on in US Capitol and White House? Congress is rejecting to vote funds for fighting mosquitoes and preventing vector borne diseases including Zika, Dengue and Chikungunya. President Obama has decided to move Funds allocated for Ebola to Zika (600 M$). May be a political way to push Congress to feel more responsible and liable just in case of an outbreak of Zika or an increase of microcephaly and especially at the time where Republicans and its representative Donald Trump, are not in the best shape. How avoiding to think about the TV fiction House of Cards and how politicians manipulate each others to achieve their goals. But today is no longer a fiction but true real life.
We are far from Public/Global Health issues and PHEIC despite the need for sponsoring in Vitro Laboratory studies or in Vivo Epidemiology surveys in order to bring on the table some seeds to grind for a better understanding of the pathogenesis and neurotropism of Zika virus.
While we are observing an after-peak of Zika cases in Colombia and expecting no longer to reach 600.000 despite stats predictions, what is going on in Brazil and what do we know as of today about Zika virus and its pathogenesis?
What has been confirmed from In vitro studies?
- Zika virus crosses placenta barriers;
- Zika virus crosses blood-brain barrier;
- Zika virus can infect fetus;
- Zika virus has neurotropism;
- Zika virus is responsible for:
- Guillain-Barré Syndrome (GBS)
- Zika virus is linked with microcephaly during the Q1 of pregnancy.
When comparing Brazil/Colombia at the time being, meaning with some delay in the observance of microcephaly due to later spread of Zika virus in Colombia, on 61.393 suspected cases, 11.239 pregnant, zero microcephaly recorded so far in this cohorte but Colombia has identified 50 microcephalies, under investigation, of which only 7 under review for Zika virus while waiting for 25 (half of the cohorte) final results. We would be close to 2/10.000 prevalence or less with regards microcephaly related to Zika virus…more or less the historical prevalence of microcephaly in Brazil (26 times above in 2016).
Questions remaining without answer:
- Has Zika virus mutated since arrival in Americas/Brazil?
- Is there possible co-infection:
- with Dengue?
- with CMV, Rubella?
- Is there possible dual cause:
- with a chemical?
- with larvicide, pesticide?
- with Global Health issues (environment,Socio-economics)?
In a previous blog, we pointed out the choice of Colombia as a control group for the prevalence of microcephaly in link with Zika virus in order to answer the question about Zika virus as causative microcephaly.
So May we confirm, as WHO and CDC are delivering statement, that microcephaly is definitively related to Zika virus? More evidence required by answering questions.
If WHO has launched a PHEIC with regards Zika virus and possible side effects/defects like Guillain-Barré Syndrome (GBS) or microcephaly, several scientists are now pointing out other root causes for explaining both the nature of the disability and the spread of the outbreak in South America, moslty in North-East Brazil.
Map of microcephaly in Brazil
By reviewing other risk factors which might be responsible or co-acting with the Zika virus, there are at least two questions unanswered about the key role of virus for microcephaly:
- Why microcephaly newborns are concentrated in North-East states of Brazil?
- Why socio-economics are impacting the rate of microcephaly in this location?
- Tentative answers raising global warming including but not limited to El Nino to increasing the spread of the zika outbreak by helping the growth of the vector (Aedes aegypti mosquito), are not totally convincing; even if climate change is acting as a promoting/contributing factor.
- How socio-economics issues could impact women of the childbearing age or pregnant?
- poverty,malnutrition,low access to health facilities or family planning;
- environmental factors (air/water/soil pollution or contamination,waste,…);
- hygiene & sanitation.
all of global health concerns…
Now by addressing the use of a huge amount of one chemical agent,pyriproxyfen larvicide, for a while in North east Brazil (also since 2014 in Argentina), in order to sterilize potable drinking water by eradicating disease-carrying mosquitos, may we review at International level the root causes tree of microcephaly in Brazil. One critical point is we shall no longer avoid the debate…
“Given these toxic effects of pesticides and that they are more heavily used in Brazil’s northeast region, it is not unreasonable to think that, at least in some cases, microcephaly may be due to excessive use of toxic pesticides and that these effects, have been unmasked by the Zika virus infection. It is also possible to think that microcephaly in children may have a multi-causal origin.”
As always, precautionary measures are recommended before validating the quote:
“Instead Abrasco suggests that this strategy is in fact driven by the commercial interests of the chemical industry, which it says is deeply integrated into the Latin American ministries of health, as well as the World Health Organization and the Pan American Health Organisation.”