<prompt> Incubation period for diptheria and salmonella is1-2 days and 20-40 days2-6 days and 7-21 days2-6 days and 10-14 days1-2 days and 10-14 days  <response>: Diphtheria Causative agent : Corynebacterium diphtheriae, a gran positive non-motile organism Diphtheria is an endemic disease in India Source of Infection Carriers are more impoant as source of infection: 95 of total disease transmission Nasal carriers are more dangerous than throat carriers Incidence of carriers in a community : 0.5-1 Immunization does not prevent carrier state Incubation period : 2-6 days Mode of transmission Droplet infection main mode, directly from cutaneous lesions anf fomites. Ref : Park 25th edition Pgno : 235 Typhoid Causative agent : Salmonella typhi Reservoir of infection : Man cases and carriers Source of infection : Faeces, urine of casescarriers primary source and water, food fingers, flies secondary sources Incubation period: 10-14 days Mode of transmission : Faeco-oral route, urine-oral route Ref: Park 25th edition Pgno : 174,258 