Vaccines protect populations in two ways. Those who are themselves vaccinated get the strongest protection. However, those unvaccinated members of the population also benefit from "herd immunity" -- the lack of sufficient potential hosts in the surrounding community. Herd immunity is sufficient to protect the small percent of the population who cannot be vaccinated for medical reasons (primarily very young babies and those with compromised immune systems).
Unions similarly provide "herd immunity" to an economy, when membership numbers are high enough. Union workers earn significantly more, on average, than non-union workers in similar jobs. However, even non-union workers benefit when employers must compete with union shops for the same labor pool. On the Las Vegas strip, Sheldon Adelson's casinos are famously non-union. However, he must compete with his unionized neighbors for employees, so his pay and benefits are comparable to those negotiated by the Culinary Workers Union. Adelson plans less largesse in Spain, where he got the government to exempt him from many of their labor regulations and allow him to import low-paid guest workers from Morocco for his proposed Euro-Vegas complex.
In recent years, the anti-vaccine movement has been growing, and union membership and clout have been declining. Both trends have thrived on ignorance (of medical science and of history and economics). As a result, once-rare diseases are making a comeback, and Americans' standard of living has been in decline:
In short, even though an hour of work by the average worker produced close to twice as much in 2007 as in 1975, his/her hourly wage declined...Between 1949 and 1974, the workforce became twice as productive and, at the same time, the hourly wage of production and non-supervisory workers rose 66 percent to $18.63 from $11.24. Why such a drastic change after 1974? One key reason is that labor union membership was at historically high levels between 1949 and 1974...Since 1974, union membership has dropped precipitously. In recent years, less than 14 percent of workers worked under collectively bargained contracts.Vaccines are not always effective, and they occasionally have unwanted side effects. However, most people have far better odds of survival if they are vaccinated, and society as a whole is much healthier when at least 93% of the population partakes. Likewise, unions do not always perfectly represent the best interests of their members. Like all human institutions, they are prone to corruption. However, our nation was much better off when unions were strong. The people who buy into the voodoo economics of supply-side tax cuts and anti-union legislation have a lot in common with the ones who buy into Jenny McCarthy's anti-vaccination bullshit.
Famous libertarians Penn and Teller illustrate the logic and science behind vaccination: