If you are living, like me, on the northern hemisphere of our planet, then you know that winter is coming. Tomorrow, summer time daylight saving will end in many countries and darkness will take most of our day, until spring.
This will also be the season where Influenza viruses will circulate in abundance, some old, some new. If we are lucky, we have already met the old ones in previous years, and our immune system will recognize them. It's the new ones we should be concerned with most. They emerge from the bodies of their hosts with a new appearance; a make over. When they infect their host, they will, in fact, mix and mingle with other flu viruses they meet. Because, make no mistake, people will get infected with more than one flu virus at a time. And we become a biological dating site, where new generations of virus are born and emerge to the world. Some of these new generations will just have a new coat, a new disguise to evade the immune memory of the population. But others, they will have mutated in a whole new type, recombined entire parts of their virus-parents, and some of these combinations no man alive may have encountered before.
And we become a biological dating site, where new generations of virus are born and emerge to the world.
You know what makes matters even worse? Humans are not the only host for flu virus. They can infect and multiply in birds and pigs too. So in most countries were birds, pigs and humans live close together, we offer massive biological dating sites for the influenza virus to generate new types, that the world has not seen before.
You think this only happens in China, in remote rural areas? Wrong. Take a look at the map below, made in 2003 in the Netherlands, where poultry (chickens) and pigs are packed with hundreds of thousands together on an industrial scale in productions farms. And the Netherlands is the most densely populated country of Europe. Seventeen million people living in close proximity with 100 million chickens and sixteen million pigs. An influenza virus' paradise.
And do you think you can only be infected by another host with influenza by touching them at close distance? Wrong again. Look at this video in an article of the New England Journal of Medicine. It shows you how far a sneeze travels.
In addition, infected slime droplets from flu patients can stick to any surface that you and I can touch with our bare hands: door knobs, taxi cab seats, ticket counters at the train station, railings at the base ball or soccer stadium, the report card that your grand child brings home from school. You name it. The list goes on.
And the Netherlands is the most densely populated country of Europe. Seventeen million people living in close proximity with 100 million chickens and sixteen million pigs. An influenza virus' paradise.
So, do we hide? Do we stock our basement with food for 22 weeks - because that is how long the flu season can last each year - and barricade our doors?
No. We vaccinate.
Flu vaccination is our best way of protecting against the new strains that emerge each year. While we enjoy summer on the northern hemisphere, influenza specialists all around the globe hunt for new types and flu virus with new wardrobes on the southern hemisphere. During the southern winter, they trace, catch and harvest these new flu viruses and use them to produce a new generation of vaccines, able to protect vulnerable people from these new threats.
And those vaccines offer the best chance to protect our vulnerable people - the very old, the very young, those with cardiac diseases, diabetes, kidney diseases, lung diseases etcetera - from an infection that could devastate their lives, or kill.
And now you may think. "Ah, so this is only risky for the vulnerable. I am healthy, so I do not need this vaccine". Wrong again. Though it is true that healthy adults have a much lower risk of dying from a new influenza infection, it still happens. Or hospitalisation, even intensive care.
But the most pressing reason for healthy adults to vaccinate is the vulnerable group around them. Parents and grand parents, or patients. This is why Health Care Workers have duty to take flu shots every year. This is not only a medical duty, it is a moral one too, as Dr. Stanley Plotkin tells us in the excellent e-course on seasonal flu vaccination, freely available at the ECDC Virtual Academy.
So Winter is coming, and I know what I am going to do to prepare myself.