Prior to the Zika virus it was generally thought that microcephaly (small head—small brain) was an expression of abnormal formation secondary to developmental intrinsic causes, genetic in origin. Then comes the microcephaly secondary to a Zika virus infection. So, in these cases it was not a genetic cause but an infection origin.
The history of medicine has shown many diseases thought to be of environmental causes or cause unknown was shown to be infectious in origin when the microscope was invented and causative bacteria were seen.
Further etiologies were determined when the electron microscope let researchers see the virus. Thus it appears that all these conditions thought to be of unknown etiology were caused by infection.
It seems we are on the verge of more breakthroughs as researchers look for infectious agents as the cause of cancer, inflammatory bowel disease and the auto immune conditions. A perfect example in my professional career is the stomach ulcer. As a medical student I was told duodenal/stomach ulcers were caused by poor diet, “nerves” and stress. Then, low and behold, a physician demonstrated the ulcer to be caused by a bacteria, H.pylori! Instead of resorting to surgical removal of the ulcer we now threat with an antibiotic and the ulcer heals.
Whether it is the Zika virus or the H.pylori bacteria, infection once again comes to the forefront. Researchers have found infectious particles, prions, smaller than a virus to be the cause of human disease. We must learn from history and current conditions and realize at least in the past, disease etiology riddlers have been solved by finding the infectious agent.
I am sharing these thoughts with you, the reader, so that you can be informed parents. Time will tell and I feel by reflecting on the past it sometimes opens the gate to the future. The Zika infection shows what was thought to be a genetic condition, congenital microcephaly can in fact be a sequela to an intra uterine infection. The next medical frontier is intra cellular space where micro particle can disrupt cell function and cause clinical disease.