Impact of Influenza on the Brain

From Whats Going on in There? : How the Brain and Mind Develop in the First Five Years of Lifeby Lise Eliot, Ph.D.; 2000 October 3; page 80

There have been some suggestions that maternal flu infection can have long-lasting effects on a baby’s brain. While influenza is nowhere near as dangerous as the other infections we have considered — it has not been linked to any specific malformations, prematurity, or other obvious adverse outcomes of pregnancy — some researchers suspect that it increases the odds of later-emerging mental deficits. For instance, one line of research has detected a link between prenatal flu and schizophrenia, suggesting that the viral infection, particularly around the sixth month of gestation may interfere with neuronal migration in such a way as to disturb later cognitive and emotional functioning. Another study suggests that second-trimester influenza infection increases the chances that a child will be dyslexic, perhaps because of similar neuronal perturbations. Yet another hints that influenza in the one month before or three months following conception may increase the chance of neural tube defects, even if the mother did not run a temperature.

All these findings must be regarded as highly speculative at this point. But given the potent effect of other viruses on prenatal brain development, the idea that influenza might significantly perturb neuronal organization is not unreasonable. Further research may clarify these issues soon, so pregnant women will know how vigilantly they need to protect themselves from catching the flu.