That is true - but as most major diseases are vaccinated against in developed countries, it will not be such a problem as in the developing nations. However, if the Philippines is anything to go by, I don't think many of the children followed isolation rules or any other preventative measures. But, as you say, it is part of the health implications of the virus and effects stemming from control methods which will be interesting to see over the next few years. There is a set of scales here in terms of health implications.