Utopia, you are standing in it!

Some public goods can be not provided much at all if even a few do not contribute – free ride. These are called weakest shot public goods. The link in the chain is only as strong as the weakest link for some public goods. The fighting against communicable diseases is an example of that.

The classic example given by that brilliant applied price theorist Jack Hirschleifer is a dyke or a levee wall around a town. It is only as good as the laziest person contributing to its maintenance on their part of the levee wall. Vicary (1990, p. 376) lists other examples:

Similar examples would be the protection of a military front, taking a convoy across the ocean going at the speed of the slowest ship, or maintaining an attractive village/landscape (one eyesore spoils the view).

Many instances of teamwork involve weak-link elements, for example moving a pile of bricks by hand along a chain or providing a theatrical or orchestral performance (one bad individual effort spoils the whole effect.)

Another example of weakest shot public goods is community cooperation after disasters. The quality of the public good provided is equal to the contribution of the weakest person who may start a criminal rampage despite the good efforts of everyone else.

People tend to be more cooperative after natural disasters. They realise their contribution is more important than normal to the maintaining of the social fabric which is currently hanging by a thread.

Vaccinations are example of a weakest shot public good. The quality of herd immunity depends fundamentally on just about everybody contributing by getting vaccinated. Not all public goods depend on the some of those contributions made. In some cases  just a few people choosing to free ride can greatly undermine the public interest.

The reverse of a weakest shot public good is best shot public goods. Example of this is the development of vaccines themselves. The public good is only as good as the best effort at developing the new vaccine with all the others efforts pointless because the best of the vaccines is chosen.

The most curious people in New Zealand to oppose measures to address the under provision of weakest shot public goods are the New Zealand Greens.

https://twitter.com/KevinHague/status/642505850360213505

The Greens are usually the 1st to stress the importance of communities working together for the common good.

https://twitter.com/KevinHague/status/642530277177192448

Herd immunity protects those who cannot be safely vaccinated including new babies, those for whom the vaccine fails, which occasionally happens, and those with compromised immunity such as adults receiving chemotherapy.

Deliriously hot @guardian sim shows why anti-measles jabs help protect your whole community gu.com/p/45f7e/stw http://t.co/H31ZKbXkqg—
Info=Beautiful (@infobeautiful) February 05, 2015

We are all in this together. It is time for the New Zealand Greens to stop pandering to those are only think of themselves and what a free ride on others including the very sick and new babies.

Source: NOVA | What is Herd Immunity?

Herd immunity requires vaccination rates of about 94%. The near universal vaccination rates required for herd immunity are to smaller margin to pander to an awkward squad who do not want to vaccinate despite the harm they do to others.

Harm to others is grounds and has always been grounds for public policy and public health interventions. Instead, the Greens are anti-science, anti-public health.

Measles is the most contagious disease known to man. Seven children died in New Zealand in the last measles outbreak in 1991. The dead are already too many from the anti-vaccination quacks and cranks.