“I don't think he should be kept out of school forever but it seems sensible to apply a 3 week 'quarantine'.
We do it for other much less serious illnesses so itseems ridiculous to not take precautions in this case.” We don’t quarantine for any illnesses which are not yet symptomatic. Even illnesses like chicken pox and measles we only quarantine once symptoms are apparent, and rightly so, even though e.g. cp is contagious for several days before symptoms appear (unlike ebola).
People really do need to take a step back and seriously think about what it is they are proposing here – essentially that anyone from certain countries be ostracised from society for a three week period “just in case”. In so doing you are labelling all people from certain African countries as a risk to our children when this simply is not the case. If we’re not careful we’re going to end up with a situation where everyone who is black will be viewed with suspicion “just in case” they’ve been to one of “those countries” and could pose a risk. Is this the kind of society we want to live in? Perhaps we should give everyone from Siera Leone a bell on entry which they can ring at passers by to declare themselves to be “unclean” as in biblical days. 
The death rate from ebola is currently high not because of the strain of the virus but because of the infrastructures of the countries where it has emerged. In the cases where people have been brought back to the UK/US to be treated they have iirc all survived. Death rates from other diseases such as malaria are excrutiatingly high in Africa not because of the illness but because of the infrastructure to deal with it.
And the
\link{http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/case-counts.html\figures}
are also important: Siera Leone for instance has a population of 6 million people. The total deaths from ebola in Siera Leone is 879. The total confirmed cases in Siera Leone is 2455, so actually their death rate is much, much lower than the 70% which has been bandied about on this thread and elsewhere. But 2455 as a percentage of six million is neglidgeable. But the infrastructure of a country needs to be taken into account when looking at these stats – one in eight women die in childbirth in Siera Leone for instance, so you simply cannot commute a figure of a 70% death rate from a country with that kind of infrastructure to one like the UK.
A bit of perspective goes a long way IMO. Whereas hysterical panic achieves nothing.
And no, it is not comparrible to deciding whether or not to vaccinate your child. People choose not to vaccinate their children for any number of reasons – and that choice is generally an informed one. Choosing to complain about a child visiting your school on the basis of where he comes from and the headlines you might have read is nothing short of ignorant and there is nothing informed or intelligent about it.