For highly infectious pathogens where cases may be asymptomatic (i.e. norovirus, Hepatitis A), it may be necessary to require a negative stool or multiple tests before returning to work
 

With many pathogens, ill cases can continue shedding the organism in their stool for days to weeks even after they stop experiencing symptoms
 

Consult epidemiology and/or healthcare providers on when food workers can return to work