Which vaccine gives herd immunity
If the herd immunity is sufficiently high the occurrence of an epidemic is regarded highly unlikely. If that level of immunity is maintained and stepped up by an ongoing immunization programmed to the point where the susceptible populations are reduced to a small propoion of the population. This has been achieved in diphtheria and poliomyelitis. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 111
OPV
Typhoid
Cholera
None
Epidemiology