Back around the turn of the 20th century (when many immigrants were coming to the U.S.), they were put into quarantine until it was determined they didn't have infectious diseases. People who had tuberculosis and certain other diseases weren't allowed to enter the country. The only vaccine that was available was the one for smallpox. Then the DPT vaccines came along, and many children were saved. The polio vaccine was invented in the 1950's, and then the MMR and chickenpox vaccines came later. Now we have immigrants from countries where there aren't vaccines entering the country without restriction, and they expose people who aren't vaccinated. Then there are the people who claim they have a religious stand against vaccines. These people don't understand the consequences of so-called "childhood diseases". They can cause encephalitis, shingles, deafness, sterility and other things. About the only thing that will get the attention of the unvaccinated individuals is to quarantine them for the duration of the illness. If that means missing work or school, then that's their consequence.