Unfortunately, those who dined at the Milan, Illinois McDonalds restaurant located at 400 West 1st Street during the month of July, and maybe even June, and are still not yet sick are not yet out of the woods.  Hepatitis A has an incubation period–i.e. the time that elapses between ingestion of the virus and onset of illness–is longer than most foodborne pathogens at 15 to 50 days.  It appears that infected workers at the restaurant may have worked until as late as July 13 or 14.  This means that, assuming July 14 is the last possible date of exposure, illness may not begin for a person infected on that date until the end of August, or the very beginning of September. 

At the risk of adding further stress to the lives of those now worried sick that they might become ill, the efficacy of immuneglobulin shots (i.e. the 5,366 innoculations that the Rock Island County Health Department has given) is not absolute.  It is effective in most cases (approximately 80-90%), but only if administered within two weeks of exposure.  Thus, anybody infected in June who received an injection in late July is probably not protected.  And obviously, those who dined at the restaurant at any point during the exposure period, and who did not receive an injection, are unprotected against the onset of illness as well.