I don’t know of any universal symbol.

The most common symbols used in Western newspapers, at least, are the dagger and the star of David, to indicate, respectively, Christian and Jewish deaths.

cheers ricardo — as i understand it, the dagger is used when a religious figurehead such as a cardinal or a bishop writes to the paper. I find the star of david inhabits to many biased connotations to be useful as a general symbol of obituaries. All interesting though!