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Knock wood, but my wife and I remain sniffle-free so far. Our boy (almost 5) is over it. Our baby (7 weeks) still has a runny nose which we have to treat with saline drops and the aspirator (known as the "booger sucker" around our household) but seems to be getting over it. It seems like the Kleenex antivirals and conscientious hand washing have kept us safe. Good job too, it'd be the worst possible time at the beginning of the semester.
Years ago I worked my way through grad school at the local sewage treatment plant as a plant operator class B and lab tech class C. (Or a "turd herder" if you prefer, a job not nearly as unpleasant as you think.) I was told when I went to work that studies had shown that new workers typically experienced a rise in upper respiratory tract infections for the first six months, then back to normal. This isn't because our immune systems get strengthened but because workers develop the reflex of washing their hands every time they come inside, handle samples etc. Wastewater treatment operators and lab techs wash their hands an estimated 40 times per eight-hour shift.
It would be an interesting study to try and estimate how much the drop in mortality rates in the industrialized world is due just to soap.