There was a story in the NZ Herald this week regarding a Measles outbreak in Auckland and the response to this event by the Powers That Be. Whether or not the action taken (keeping unvaccinated children at home following possible contact with carriers) is correct, either practically or ethically is a question that will be endlessly discussed by others. I would like to focus on a point made in the article about vaccination coverage in New Zealand children. It was implied that approximately 25% of NZ children are unvaccinated, at the moment data is collected at childhood “milestones” 6,12,18 and 24 months of age. At 24 months the coverage is 77%, after this age no information (currently available) is collected but it is reasonable to expect that the numbers do not climb appreciably after this age.
I found it interesting that the article did not mention that compared with other developed countries this coverage is practically dismal. The coverage in the USA is >95%, though school attendance is predicated upon receiving vaccinations exemptions are available. In the UK where recently there have been concerns over vaccination rates dropping encouraging outbreaks over there, the coverage is still >80%. Even Australia has 82% coverage at age 5. The target coverage for NZ is >95%. Why do we lag behind?
According to the National Childhood Immunisation Survey conducted in 2005, 25% of those whose children do not receive the vaccinations have made this choice due to fears of vaccine safety (another 5% had concerns over a particular vaccine). 3% of respondents reported that they did not believe vaccines work at all. More mundane reasons were also quite prominent: child was on a different schedule or immunisation was done overseas – 19%, medical reasons – 11%, thought the child was vaccinated/not sure if vaccinated ~10%. A laundry list of other reasons each had <3%. Compared with the US where the reasons mostly cited were “Philosophical or Religious beliefs against vaccination” ~66%. Considering that in many states exemption due to religious reasons are about the only ones the law will accept (barring medical reasons) this is likely to cover a wider array of actual reasons.
How should NZ tackle the vaccination issue?
See also:
Evidence Based Thought: What’s wrong with catching the Measles?
Scepticon 
Yikes! I hadn’t realised our figures were so low!
Don’t know if you’ve seen it but the Science Media Centre has a new post out on the safety of the Gardasil vaccine – very relevant considering how widespread people’s concerns about vaccine safety seem to be.
Very interesting, thanks! The post touched very tangentally on something that I have been thinking about in that while the opponents may endlessly argue about it not being 100% effective, to me that isn’t the point. It’s another way to reduce the risk, not remove it entirely. Nay sayers always seem to view these things in black and white, if it’s not completely effective then it’s useless.
Only 77% coverage @24 months for MMR? Crap, even not having a background in epidemiology, aside from stuff from Orac, that means it’s exceedingly easy for measles to spread…
As for dealing with it? Given the school policies in the US of students having to be fully vaccinated in order to attend school is working, it might be an idea to put it into practice in NZ. Plus a good deal of public education about the impacts of measles, and the safety of the MMR vaccine, designed to counter much of the lies and BS spread by the anti-vaccination groups. An emphasis on relative risks might also be useful, since people seem to weight immediate outcomes perceived as highly negative much higher than long-term negative outcomes, regardless of the actual probability of the immediate negative outcome.
There are several good points here that you raise. First about vaccine coverage, the actual numbers of children vaccinated is one thing but the additional percentage for whom the vaccine is not effective (eg. poor immune response etc.) does mean that these numbers are quite concerning and provides further basis for the seemingly draconian action taken in this case.
I am certainly not averse to making vaccination compulsory for school children but I suspect that this would be difficult to implement due to a percived reduction of autonomy. Hey we still have people complianing about Flouride in the water, vaccines are more invasive than that. It also raises the question of whether exemption should be given for more that just medical reasons. As noted above the US will allow exemptions for religious reasons even though this goes against the spirit of the policy. Should we follow suit? or do we dismiss religion as a valid reason for putting the wider community at risk? How would this decision affect public backing of the project? In addition this provides a cover for those who want to opt out of the vaccination program for other reasons see here.
Finally on risk, the is a tendency for people to be more averse to causing harm that allowing harm to occur, thus despite the vaccine safety record the fear that the parent the “did” something that “caused” thier child harm will remain. How do we overcome this? Education may be the answer but I suspect it will be more complicated that that.