A report from the Argentine doctors’ organisation, Physicians in the Crop-Sprayed Towns,[1] challenges the theory that the Zika virus epidemic in Brazil is the cause of the increase in the birth defect microcephaly among newborns.

The increase in this birth defect, in which the baby is born with an abnormally small head and often has brain damage, was quickly linked to the Zika virus by the Brazilian Ministry of Health. However, according to the Physicians in the Crop-Sprayed Towns, the Ministry failed to recognise that in the area where most sick people live, a chemical larvicide that produces malformations in mosquitoes was introduced into the drinking water supply in 2014. This poison, Pyriproxyfen, is used in a State-controlled programme aimed at eradicating disease-carrying mosquitoes.

The Physicians added that the Pyriproxyfen is manufactured by Sumimoto Chemical, a Japanese subsidiary of Monsanto. Pyriproxyfen is a growth inhibitor of mosquito larvae, which alters the development process from larva to pupa to adult, thus generating malformations in developing mosquitoes and killing or disabling them. It acts as an insect juvenile hormone or juvenoid, and has the effect of inhibiting the development of adult insect characteristics (for example, wings and mature external genitalia) and reproductive development. It is an endocrine disruptor and is teratogenic (causes birth defects).

The Argentine Physicians commented: “Malformations detected in thousands of children from pregnant women living in areas where the Brazilian state added Pyriproxyfen to drinking water are not a coincidence, even though the Ministry of Health places a direct blame on the Zika virus for this damage.”

They also noted that Zika has traditionally been held to be a relatively benign disease that has never before been associated with birth defects, even in areas where it infects 75% of the population.

Larvicide the most likely culprit in birth defects

Pyriproxyfen is a relatively new introduction to the Brazilian environment; the microcephaly increase is a relatively new phenomenon. So the larvicide seems a plausible causative factor in microcephaly – far more so than GM mosquitoes, which some have blamed for the Zika epidemic and thus for the birth defects. There is no sound evidence to support the notion promoted by some sources that GM mosquitoes can cause Zika, which in turn can cause microcephaly. In fact, out of 404 confirmed microcephaly cases in Brazil, only 17% tested positive for the Zika virus.

Brazilian doctors agree Pyriproxyfen is chief suspect

The Argentine Physicians’ report, which also addresses the Dengue fever epidemic in Brazil, concurs with the findings of a separate report on the Zika outbreak by the Brazilian doctors’ and public health researchers’ organisation, Abrasco.[2]

Abrasco also names Pyriproxyfen as a likely cause of the microcephaly. It condemns the strategy of chemical control of Zika-carrying mosquitoes, which it says is contaminating the environment as well as people and is not decreasing the numbers of mosquitoes. 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.

Abrasco names the British GM insect company Oxitec as part of the corporate lobby that is distorting the facts about Zika to suit its own profit-making agenda. Oxitec sells GM mosquitoes engineered for sterility and markets them as a disease-combatting product – a strategy condemned by the Argentine Physicians as “a total failure, except for the company supplying mosquitoes”.

The poor suffer most

Both the Brazilian and Argentine doctors’ associations agree that poverty is a key neglected factor in the Zika epidemic. Abrasco condemned the Brazilian government for its "deliberate concealment” of economic and social causes: “In Argentina and across America the poorest populations with the least access to sanitation and safe water suffer most from the outbreak.” The Argentine Physicians agreed, stating, “The basis of the progress of the disease lies in inequality and poverty.”

Abrasco added that the disease is closely linked to environmental degradation: floods caused by logging and the massive use of herbicides on (GM) herbicide-tolerant soy crops – in short, “the impacts of extractive industries”.

The notion that environmental degradation may a factor in the spread of Zika finds backing in the view of Dino Martins, PhD, a Kenyan entomologist. Martins said that “the explosion of mosquitoes in urban areas, which is driving the Zika crisis” is caused by “a lack of natural diversity that would otherwise keep mosquito populations under control, and the proliferation of waste and lack of disposal in some areas which provide artificial habitat for breeding mosquitoes”.