There are many news stories currently about the Zika virus, including a possible link with infant microcephaly. The news coverage is sometimes too decided on such possibilities, and it may be worthwhile to stand back a bit from decisions. Microcephaly can have several causes. I’m not a medical practitioner, but even a non-specialist can get a bit of calm perspective from reviewing some of the info sources.

The WHO (world Health Organization) website has some Q&A about the Zika virus, and includes this text:

“Should pregnant women be concerned about Zika?

“Health authorities are currently investigating a potential link between Zika virus in pregnant women and microcephaly in their babies. Until more is known, women who are pregnant or planning to become pregnant should take extra care to protect themselves from mosquito bites.

“If you are pregnant and suspect that you may have Zika virus disease, consult your doctor for close monitoring during your pregnancy.

“What is microcephaly?

“Microcephaly is a rare condition where a baby has an abnormally small head. This is due to abnormal brain development of the baby in the womb or during infancy. Babies and children with microcephaly often have challenges with their brain development as they grow older.

“Microcephaly can be caused by a variety of environmental and genetic factors such as Downs syndrome; exposure to drugs, alcohol or other toxins in the womb; and rubella infection during pregnancy.”

[end of quote from WHO] Source URL: http://www.who.int/features/qa/zika/en/

Another possible cause of microcephaly is exposure of the fetus to radiation. Here is a text from the “Mother to Baby” website supported by the the state of Illinois, USA:

“CNS [Central Nervous System] defects and Growth Retardation

“Manifestations of in utero irradiation in humans are microcephaly, mental retardation and other CNS defects, and growth retardation (Mole 1991). Microcephaly is the most common malformation reported after exposure to a high dose of radiation during pregnancy. In one study, 25% of children exposed to more than 100 rads of radiation during gestation were microcephalic or hydrocephalic (Goldstein and Murphy 1929, 1930). Almost all microcephalic children irradiated in utero were mentally retarded and had short stature as well. The incidence of microcephaly rose with increasing exposure (Brent et al. 1993).”

[end of quote from “Mother to Baby” website] Source: http://fetal-exposure.org/radiation-and-pregnancy/

Another, non-medical, resource on the relationship between radiation exposure and microcephaly is found in Susan Southard’s book “Nagasaki: Life After Nuclear War” (2015): “Microcephaly — a condition defined by a significantly smaller-than-average head size in proportion to a child’s body, reduced life expectancy, and decreased brain function — occurred in approximately 15 percent of children exposed to radiation in utero up to 1.25 miles from the hypocenter [of the atomic bomb explosion], a rate almost four times higher than for those not exposed.” [page 177]. Also, on page 190,. a study is cited that exposure during weeks 8-15 after conception was much riskier than exposure in later weeks of pregnancy.

Bottom line for a cautious non-specialist reader: There can be a variety of causes of the observed high incidence of microcephalic infants. A possible connection with the Zika virus is worth investigation, but also it is advisable to investigate possible presence of other causative factors. WHO is doing those investigations. We should not rush to decision and action about a possible mosquitoes and Zika virus causation, if that would result in other avenues of inquiry being abandoned. It is worthwhile to reduce mosquito populations in general, because of other diseases they can transmit (Dengue fever, for instance). But, regarding Zika, don’t let media frenzy divert investigative focus.

Best wishes,
Ken Roberts
03-Feb-2016