The only thing that differs now from the 'olden days' is that it spreads so fast due to air travel. It's just one transoceanic flight away. H7N9 is alive and well in the bird population and it will likely pop up like H5N1 for a while. It can spread human to human, but, thus far it hasn't been that aggressive or we would be in the middle of a huge pandemic.
nCoV-MERS is likely far more common in the Middle East than we know and probably a lot more people are surviving it than we know. I don't expect a lot of transparency from that region. As far as 'risk assessments' go, keep in mind that any country that issues a risk assessment is doing it based on the conditions in that country as of today. As of today, in the US, you are not likely to contract nCoV.....as cases pop up here and there, and it gets more common your risk goes up.
nCoV-MERS is likely far more common in the Middle East than we know and probably a lot more people are surviving it than we know. I don't expect a lot of transparency from that region. As far as 'risk assessments' go, keep in mind that any country that issues a risk assessment is doing it based on the conditions in that country as of today. As of today, in the US, you are not likely to contract nCoV.....as cases pop up here and there, and it gets more common your risk goes up.