Zika and Microcephaly: Pieces of the Puzzle

by | Apr 28, 2016 | Infant and Children's Health, Pesticides and Solvents, Pregnancy and Lactation

Written by Joyce Smith, BS. An increasing mosquito population, overuse of pesticides, vaccines and the Zika virus may all play a potential role in the increasing prevalence of microcephaly in Brazil.

The Zika virus was discovered in a rhesus monkey in the Zika forest of Uganda in 1947 and was first reported in humans in 1952. 1 Like its relatives, the yellow fever virus, dengue virus and West Nile virus, it is spread by the ubiquitous Aedes mosquitoes. Lab tests such as ELISA testing and Reverse-transcription PCR are often necessary to differentiate this virus from its cousins. 2

Zika was first identified in Brazil in 2015 where it was associated with microcephaly in the infants of some women who were pregnant when they contracted the disease. 3 Clinically, it is a self-limiting febrile illness presenting with low fever, sore muscles, headaches and rarely a mild rash. However, there is increasing evidence of a link between Zika virus and Guillain-Barré syndrome and microcephaly. 4 5 6 Since it is spread from mother to fetus, there is also concern that an infected mother will have a microcephalic baby.7

Does the Zika infection cause microcephaly?

Interestingly in 2014, only 150 cases were reported for the entire country of Brazil, a very small amount for such a large country with nearly 3 million annual births. 8 Yet approximately one year later (February, 2016) Brazil reported 41,801 cases of which only 404 were actually microcephaly.8 Of these 404 cases, only 17 actually contained the Zika virus. (Only 4.2% were shown to have any connection with Zika.) The poverty-stricken northern state of Pernambuco accounts for one-third of these cases. February 4th of 2016 Colombia’s President Juan Manuel Santos reported “no evidence of Zika having caused microcephaly in his country,9 though it has diagnosed 3,177 pregnant women with the virus. 9

On the other hand, approximately 25,000 infants in the United States will be diagnosed annually with microcephaly (head circumference <-2 SD). That is 25,000 per year in a country with a population of just under 323 million. 10 Compare that with, at most, 3,500 cases in Brazil, a country of about 209 million people. 11 The US does not have a Zika problem. However, microcephaly may result from any insult that disturbs early brain growth and can be seen in association with hundreds of genetic syndromes. 12

So what may have contributed to these sudden outbreaks of microcephaly in Brazil in 2015?

Factors as well as cofactors may have played a pivotal role. Among them are the following:

An Emerging Mosquito Population:

It was also in July of 2012 that the GM mosquito was introduced into Brazil with the goal of reducing the mosquito population and “the incidence of dengue fever.” However, the GM mosquito is engineered so the offspring (larvae) will die off before they mature, with the caveat that tetracycline is not present during their development. Tetracycline can override the DNA of the GM mosquito. Brazil ranks 3rd in the world for tetracycline use in its animals. According to an American Society of Agronomy study, 75 % of this antibiotic is excreted back into the environment and feeds the GM mosquito. This, coupled with a climate of extended high temperatures and stagnant water, has increased the survival rate of the GM mosquito from an estimated 4% to 15% or more. 13

Overuse of Pesticides and Herbicides:

Brazil also appears to be reckless and irresponsible in its use of pesticides. Many highly toxic and banned pesticides that are linked to congenital defects are used liberally and without proper equipment and safety protocols. GM crops, introduced by the Bill and Melinda Gates Foundation (BMGF) in 2012. 14 GM crops helped Brazil become the world’s top exporter of certain agricultural products. 15 Unfortunately, GM crops require larger amounts of pesticides than non- GM crops. In fact, in the year 2012, Brazil purchased more pesticides than the United States. 16 Following the WHO’s classification of glyphosate as a “probable carcinogen”, Brazil’s National Cancer Institute labeled GM crops responsible for the massive use of insecticides. 15

A powerful agricultural lobby and weak government enforcement has made violations of pesticide rules a common occurrence in Brazil.16 Women are in direct contact with pesticides by inhaling and absorbing them through the skin. 17 A study addresses the pesticide use on tomatoes with respect to workers who handle and apply the toxic, banned pesticides: “Women washed the pesticide application equipment, generally in the work environment, without protective clothing or without observing the recommended three-fold washing process.” 18 Of the women who participated in the study, 32% were pregnant more than 5 times, 71% reported miscarriages and 11% reported having mentally and/or physically impaired offspring. Lab analysis revealed ethylene thiourea (ETU), an endocrine disruptor, exceeded maximum residue limits by 78%.19 This pesticide can potentially cause goiters, birth defects, and cancer in some experimental animals 18 20 and is classified as a potential human carcinogen by the United States EPA. 18

Today there is also an ongoing controversy regarding the possible adverse effects of glyphosate on the environment and on human health. Reports exist of neural defects and craniofacial malformations from regions where glyphosate-based herbicides are used. 21 Research also validates the neurological damage done by these herbicides. 22

The Vaccine Initiative:

A growing number of pertussis-related deaths (80,068 “suspected cases”) with 80% occurring in infants under 3 years of age were reported from 2007-14. 23 7 In late 2014, Brazil’s Ministry of Health, in an attempt to control the resurgence of pertussis, mandated the TDaP (Tetanus, diphtheria, and acellular pertussis) vaccine for all pregnant women as part of its routine vaccination program. Women between the 27th and 36th weeks of pregnancy and up to 20 days prior to the expected date of birth received TDaP produced by GlaxoSmithKline.

Because of a shortage of the DTaP vaccine, the highly reactive DTP vaccine was also administered along with the Measles Mumps Rubella (MMR) vaccine. None of these vaccines is considered safe during pregnancy. The FDA cautions against the safety of DPT for pregnant women and GSK warns of inadequate toxicity and fertility studies and that TDaP should “be given to a pregnant woman only if clearly needed”. 24 Vaccines including the pertussis containing DTaP was among the vaccines associated with brain inflammation and seizures in newborns and infants. 25 26 Other recent studies validate the brain damage done by highly neurotoxic aluminum adjuvants that can pass through the underdeveloped blood brain barrier of the growing fetus and newborn to do neurological damage, including autism and other auto immune manifestations. 27 28

The Latin American Collaborative Study of Congenital Malformations (ECLAMC) produced a document that analyzed the occurrences of microcephaly following the reported increase in microcephaly cases in Northeastern Brazil in 2015.Their document concluded the following: “In summary, when we ask ourselves if there is a microcephaly epidemic in Brazil, or if there is a causal relationship between maternal infection with the ZIKV and children born with microcephaly, we face problems in all epidemiological steps to clarify the Rumor.” 29

It is evident that Zika virus along with the emerging mosquito population, the vaccine initiative, and the increasingly excessive use of poisonous pesticide and herbicides may have all played a role in the increasing incidence of microcephaly. This begs the question, “Is Zika really the problem and will a vaccine against Zika reduce the incidence of microcephaly?”

Addendum: A special report, just published April 18th, 2016, in the New England Journal of Medicine states that, by using both Shepard’s and Bradford Hill’s criteria, the authors were able to conclude the following: “sufficient evidence has accumulated to infer a causal relationship between Zika virus infection and microcephaly and other severe brain anomalies.”30

References:

  1. Burd I, Griffin D. The chasm between public health and reproductive research: what history tells us about Zika virus. Journal of assisted reproduction and genetics. 2016:1-2.
  2. Campos GS, Bandeira AC, Sardi SI. Zika virus outbreak, Bahia, Brazil. Emerging infectious diseases. 2015;21(10):1885.
  3. Imperato PJ. The Convergence of a Virus, Mosquitoes, and Human Travel in Globalizing the Zika Epidemic. Journal of Community Health. 2016:1-6.
  4. Shakib K. Epidemic of Zika virus and maxillofacial surgery. British Journal of Oral and Maxillofacial Surgery. 2016.
  5. Cao-Lormeau V-M, Blake A, Mons S, et al. Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia: a case-control study. The Lancet. 2016.
  6. Tang H, Hammack C, Ogden SC, et al. Zika virus infects human cortical neural progenitors and attenuates their growth. Cell Stem Cell. 2016.
  7. Sáfadi MAP. Pertussis in young infants: a severe vaccine-preventable disease. Autopsy & Case Reports. 2015;5(2):1.
  8. Cáceres M. The Zika-Microcephaly Theory’s Got Big Problems.
  9. news Yc. Colombia’s President Juan Manuel Santos said Saturday that there’s no evidence Zika has caused any cases of the birth defect known as microcephaly in his country, though it has diagnosed 3,177 pregnant women with the virus. 2016, February 4th.
  10. USA C. WUnited States Population Clock. 2016.
  11. Countrymeters. Brazil Population. 2016.
  12. Ashwal S, Michelson D, Plawner L, Dobyns WB. Practice Parameter: Evaluation of the child with microcephaly (an evidence-based review) Report of the Quality Standards Subcommittee of the American Academy of Neurology and the Practice Committee of the Child Neurology Society. Neurology. 2009;73(11):887-897.
  13. Bernish C. Zika Outbreak Epicenter in Same Area Where GM Mosquitoes Were Released in 2015. 2016.
  14. Bill and Melinda Gates Foundation Join Uup to Improve Health and Development in Sub-Saharan Africa and South Asia. 2011.
  15. GMWATCH. Brazil’s National Cancer Insstitute names GM crops a s cause of massive pesticide use.
  16. Prada P. Why Brazil has a big appetite for risky pesticides. Reuters Investigates. 2015.
  17. Aris A, Leblanc S. Maternal and fetal exposure to pesticides associated to genetically modified foods in Eastern Townships of Quebec, Canada. Reproductive Toxicology. 2011;31(4):528-533.
  18. Araujo A, Augusto L. Developing country hazards-Tomato production in Brazil–Poor working conditions and high residues threaten safety-A study of pesticide use on tomatoes in the Northern State of Pernambuco. Pesticides News. 1999(46):12-14.
  19. Burwell USDoHaHSSSM. Report on Carcinogens, Thirteenth Edition. 2009.
  20. Koller VJ, Fürhacker M, Nersesyan A, Mišík M, Eisenbauer M, Knasmueller S. Cytotoxic and DNA-damaging properties of glyphosate and Roundup in human-derived buccal epithelial cells. Archives of toxicology. 2012;86(5):805-813.
  21. Carrasco A. Teratogenesis by glyphosate based herbicides and other pesticides. Relationship with the retinoic acid pathway. GMLS 2012. 2013:24.
  22. Roy NM, Carneiro B, Ochs J. Glyphosate induces neurotoxicity in zebrafish. Environmental Toxicology and Pharmacology. 2016;42:45-54.
  23. Guimarães LM, Carneiro EL, Carvalho-Costa FA. Increasing incidence of pertussis in Brazil: a retrospective study using surveillance data. BMC infectious diseases. 2015;15(1):442.
  24. Food, Administration D. Product approval information—licensing action, package insert: BOOSTRIX®. Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis Vaccine, Adsorbed. GlaxoSmithKline Biologicals. Rockville, MD: US Department of Health and Human Services. Food and Drug Administration, Center for Biologics Evaluation and Research. 2005.
  25. Catherine BHF. Vaccines and Inflammation. International Medical Council on Vaccination. 2007.
  26. Barlow WE, Davis RL, Glasser JW, et al. The risk of seizures after receipt of whole-cell pertussis or measles, mumps, and rubella vaccine. New England Journal of Medicine. 2001;345(9):656-661.
  27. Tomljenovic L, Shaw CA. Do aluminum vaccine adjuvants contribute to the rising prevalence of autism? Journal of Inorganic Biochemistry. 2011;105(11):1489-1499.
  28. Wildemann B, Jarius S, Hartmann M, Regula J, Hametner C. Acute disseminated encephalomyelitis following vaccination against human papilloma virus. Neurology. 2009;72(24):2132-2133.
  29. Orioli JSL-CIM. ECLAMC final Document. 2015.
  30. Rasmussen SA, Jamieson DJ, Honein MA, Petersen LR. Zika virus and birth defects—reviewing the evidence for causality. New England Journal of Medicine. 2016.