A Theory That Raises Questions

E. Fuller Torrey, a Washington psychiatrist with a long interest in schizophrenia, said the link between early maternal infections and schizophrenia is strong. He believes that infections and immune reactions in young children, not just maternal infections during fetal life, might be involved in elevating the risk for schizophrenia.

Animal research conducted by Caltech's Patterson along with William Carpenter and James Koenig at the Maryland Psychiatric Research Center at the University of Maryland appears to support the theories of Brown and others.

Pregnant rodents given flu infections seem more likely to have offspring that show some of the behavioral symptoms of schizophrenia, such as social withdrawal and anxiety. When the effect of maternal antibodies is blocked, the offspring do not go on to develop such symptoms.

Patterson said he also hoped to see new epidemiological studies that specifically looked at whether pregnant women given flu shots had offspring with a higher risk of schizophrenia than pregnant women who did not receive flu shots.

"It is true that vaccinations do not cause the same degree of immune activation as an infection," he said. "But if you are recommending universal vaccinations for every woman who is pregnant, you are asking for increased risk for schizophrenia because some women are going to have a very strong reaction."

What should pregnant women do until useful policy conclusions can be drawn?

Experts say the best bet is probably to stick to official public health guidelines on the flu shot, and to try to limit infections and stress during pregnancy.

"I was raised in the Midwest, so I believe the best motto is, 'Everything in moderation,' " Koenig said. "Keep your life as well balanced as possible." ¿

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