Swine flu: The global perspective
A few words about how the H1N1 virus is progressing on its relentless attempt to reach every corner of the globe.
New figures from the World Health Organization show the virus has now spread to more than 199 countries and territories and that there have been more than 6,000 deaths.
Although every death is a tragedy, that is a remarkably small number given that seasonal flu is reckoned to contribute to the deaths of at least 250,000 people per year. It is yet further evidence of the generally mild nature of the virus.
Having said that, swine flu has a sting in its tail.
Australia, like several other southern hemisphere countries, has recently emerged from its winter flu season.
Deaths were low compared to seasonal flu, but hospital intensive care units had not seen anything like it in 40 years; indeed, since the pandemic of 1968-70.
It sums up the apparent contradiction about this pandemic: mild for most, but very serious for a small minority.
Those at greatest risk of complications are pregnant women and anyone with an existing health condition such as asthma. That's why these groups are being immunised first.
Unlike seasonal flu, which tends to kill the frail elderly, the average age of those who've died from the virus here in the UK is 44. One in five of those who have died had no previous health problems.
As I have said before, swine flu should not be a reason to panic - nor is it something to dismiss out of hand. We can all do our bit to minimise the spread of the virus by following good respiratory and hand hygiene.
Several of you have asked about what's happening in Ukraine which, in just a few weeks, has recorded more than 250,000 cases of flu-like illness, with 235 people needing intensive care and 70 deaths.
As far as I can make out, there does not seem to be anything unusual about the outbreak there. One health official said it was probably a reflection of the poor state of the health service that the virus had had such an intense effect.
Crucially, samples of the virus have shown that it is not mutating, so is the same H1N1 pandemic strain that is circulating worldwide. As long as that remains the case, we should feel reassured.
Finally, if the virus has spread to 199 countries and territories, does anyone know where on the planet has not experienced swine flu?