1. Considerring just the case study described above the phrase to describe best the parents aproach would be: If it ain't broke, don't fix it". In other words they didn't fully understand the benefits for the immune system in case of vaccination as explained by the health system representative, therefore they would refuse any invasive health approach if it's not a compulsory intervention ( emergency)
2. Health is considered to be the natural structural and functionsl equilibrium that the body has and unless is obvious that in that particular case, the natural adapting capabilities are not sufficient to surpass difficult circumstances, invasive health techniques are not regarded as necessary interventions.
3. Probably by describing in better terms and exemplify how children who were exposed to similar environmental factors or having more or less the same inhereted features experienced difficulties in adapting to given living conditions compared to those who considered vaccination