Themost recent update from the Department of Education lists schools that are newly closed today and others that will reopen. It also itemizes certain specific programs -- for disabled students, for example, or for kindergartners registered at one school who share a site with another school -- which will close, while the schools that host them will remain open.

It's not clear why decisions were made to close parts of specific buildings -- and even less clear how flu viruses may be contained across arbitrary, human-imposed borders in a single physical structure. To this non-epidemiologist, closing part of a school seems baffling: the virus can't discern which students it affects, or where they attend school, or which program is theirs. Viruses don't ask questions; ask any parent with more than one child what happens when one gets sick.

If the contagion is sufficient to warrant protecting some of the students in the building, why not protect them all?