Many claim the figure is in the region of 500,000 to 2 million. A new study “Medical Tourism Services Available to Residents of the United States” published in the Journal of General Internal Medicine, which surveyed 45 agencies specialising in medical tourism concluded that the total number since these agencies started is around 13,500. This chimes with McKinsey research which puts the real number at 65,000 to 80,000.

I’m not surprised by these much lower figures. The idea of a vast outflow is ridiculous. I well remember the boss of Apollo, the leading Indian hospital chain telling me that Apollo saw a few hundred westerners a year.

But the real story isn’t the tourist flows from the western countries. It is the tourist flows from countries with failing healthcare systems to countries with good medical facilities. Many of the latter are not in the West.

Take Libya. When I was last there in 2009 a senior official told me that a fifth of the population (around 1m people a year) leave for treatment abroad every year. They go in these vast numbers to Jordan or Tunisia.

Even poor countries like the Ukraine send 40,000 patients a year westwards (according to the Ukrainian Ministry of Health).

This is where the real opportunity is today and it is why individual international healthcare policies are set to explode.