Diptheria and Hepatitis A are contracted as a result of poor sanitation conditions usually. In Russia at the end of the 1980's thousands and thousands of people died of Diptheria as a result of the immunisation's not being carried on when the government collapsed. In Britain Diptheria was common before immunisation was introduced. The reason Diptheria,Whooping cough,Measles and Polio among other illnesses have been eradicated in Britainis because we have the injections to stop them given to us when we are a few months old.
Tetanus jabs usually are usually every few years,your doctor would have records of when you need one.