krissie
i answer ur question here.. i didn't reply u straight away cos I only know for hep A and B, not sure for cholera/ salmonella.
Reason for vaccination for Hep B for me is that Hep B infections result in a long term carrier status that puts u at risk of Liver Cancer/ cirrhosis.
For Hep A, cholera, salmonella.. these all cause an active infection and then there is no carrier status. Immunization just prevents active disease. Altho for salmonella, after the active disease it is shed in the faeces for up to a few months making it infective still, so this is of concern esp in workers handling food so usu. hawkers are required to be vaccinated for this. I didn't bother to vaccinate my maid actually i just make sure she's not hep b positive as my whole family is immunized and didi is but hasn't completed his vaccination yet. To me, Hep B is more infectious and has a high prevalence rate in the local population.
cholera, salmonella is spread by saliva and fecal-oral route from person to person. Cholera is a water borne bug and can be spread by drinking affected water, and eating affected food. Salmonella also from affected food and water.
Hep B is spread by blood route so unless u deal with blood products its not easily spread. Hepatitis B is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, coughing, sneezing or by casual contact.
Hep A is also by fecal oral route.
For me, i think food handlers have to be vaccinated for salmonella, but i'm not sure for about cholera.. usually cholera is associated with poor hygiene conditions and is not prevalent here.