It may be the annual “cucumber time” or Trump-fatigue, but childhood vaccination is dominating Dutch news. The problem: the proportion of children being immunized against, for instance measles, is (slowly) declining and approaches the level that offers herd protection. That is a risk for children in the time window between passive protection by mothers’ IgG and active immunisation (at 14 months) and for persons that cannot be immunized for medical reasons. We were familiar with parents refusing immunization of their kids for religious reasons (because someone forgot to mention vaccination in the bible), but now non-religious and well-educated parents do the same. These “philosophic refusals” mostly decide to do so on information derived from internet. How can epidemiology help us to curb this problem?
Consider measles, which has a classical S-I-R epidemiology: newborns start as Susceptibles, until they become infected (and Infectious) and then Recover (or not, but then they just disapper from the equations). Once the disease is introduced in the pool of susceptibles, the number of infected/infectious rapidly increases, as long as there are sufficient contacts between infectious and susceptibles. The success of disease spread results from the number of contacts between infectious and susceptibles, and as that declines the epidemic stutters to extinction. Immunization reduces the number of susceptibles (bringing kids directly from S in R, depleting the pool of S without casualties!). And now the modern world (antivaxers, internet, social media, etc) increases the number of susceptibles (as if the birth rate has exploded). And these susceptibles are no longer clustered, as in the “bible belt region”, but dispersed in inner cities.
From a theoretical point of view there are very simple and effective measures: If we forget about culling (killing all susceptibles as in veterinary medicine), changing the contact network structure could also be very effective. How to reduce contacts between infected and susceptible kids? We have 12 provinces and we are approaching 1/12th of the kid population not being immunized….
Another solution brought forward is mandatory immunization, either universal (as in Italy) or for those kids attending daycare-centers (as in Australia (I think): “no jab, no play”). Yet, both seem to conflict with our constitutional rights of self-decision and body integrity, some claim. And “no jab, no play” is discrimination and denies kids constitutional right of teaching….
If you really want to reach Dutch people, you should go through their purse, some say. The government supports parents financially (the amount inversely related to income), and why not make that reimbursement depending on vaccination (“no jab, no pay”)? Done in Australia (I think) and now proposed in our country, but 1) this creates social inequality (“you only have a choice to refuse if you’re rich”), 2) won’t be effective (“refusers typically are high-educated and high-income”). The latter, though, doesn’t hold for the typical cheap Dutchman/woman, I guess.
And then we have the intellectually ignorants that think that all problems can be curbed by better information (flyers, websites, television advertisements), more science, or that we must accept that even well-educated persons do stupid things.
If you haven’t seen the solution by now, the only alternative remaining is to consider vaccination-refusal as child abuse. For which we have laws and measures.
How this debate will end? I don’t know, but this lesson in history was in todays newspaper:
In the Netherlands, vaccination with cowpox (against the real pox) became mandatory in 1814 for all children whose parents received financial support from the authorities. In 1823 this was extended to all children attending school. Yet, religious lobbyists succeeded to allow freedom of choice in 1857. In the 1870s a large outbreak killed 23,000, and vaccination was again made mandatory. Until 1928, when religious lobbyists, again, succeeded to allow freedom of choice.
We better change our medical curriculum and bring back childhood infections.