On Vaccines, Incentives, Open Data and Public Policy

" ... When parents fail to vaccinate their children they don’t just put their own kids at risk of contracting measles, polio and other terrible diseases. Sadly, they put at risk newborns (who cannot be vaccinated) and – more critically – a chunk of the population who legitimately cannot be vaccinated or interestingly, who do get vaccinated but for whom the vaccination does not work. This is why epidemiologists refer to 'herd immunity' (it’s always nice when discussing public policy to refer to humanity as a 'herd'). Since vaccines don’t work on everyone, enough people need to be vaccinated to prevent the disease from spreading reliably. The percentages required is usually north of 80% or 90% although I’m sure it varies a little based on the communicability of the disease. Thus, what we actually have here is a free rider problem. If everyone vaccinates, then a few people opting out are probably safe if 'the herd' remains sufficiently immune to the diseases. But drop below 80% and suddenly a tipping point is reached and things can get scary. Very scary. Frighteningly, there are whole (small) schools districts in California that fall below 50% immunized. And there are normal sized school districts that sit in the 60% and 70% range. Indeed, thanks to the California Department of Public Health (CDPH), I was able to download the vaccination rates for every preschool in the state and poke through the raw assessment data myself (Sidenote: Dear CDPH administrators, please format your excel spreadsheets without merging title columns that make it impossible for users to sort the data, super frustrating). Shockingly two preschools, Kolbe Academy in Napa and the Waldorf School of Santa Barbara, had a zero kids – that is not one child - with all the required vaccines. Moreover, at Kolbe every single kid had a personal (not medical) exemption while at the Waldorf all but two had personal exemptions (meaning there parents didn’t want their kids to have vaccines) and the other two had simple not gotten around to it. Indeed at least 230 preschools in the state had kids with 'personal exemptions' from vaccines that caused total immunization rates to fall below 80%. These preschools are, in essence time bombs ..."