If the best way to fight swine flu is to avoid it, how do we still know so little about its transmission?

What’s the most important thing one should know about the flu? Knowing how not to catch it, of course. And yet, no one, not even the most informed experts know how H1N1 and seasonal influenza are transmitted.

Everyone agrees that prevention is key. Accordingly, we have received plenty of information on how to behave during a flu pandemic. A pamphlet entitled “Know How to Prepare for the H1N1 Flu Virus – Knowledge is Your Best Defence” was sent to all Canadian households by the Public Health Agency of Canada. Most of the space in this well designed pamphlet is devoted to prevention: washing hands and surface areas, the transmission from hands to eyes, nose, and mouth, coughing and sneezing into arms rather than hands, the distribution of the vaccine, and the need to stay at home if you get H1N1.

This list suggests that the flu is mostly spread by contact. And I observe that this message has arrived – a great communication success. Hand sanitizers abound and the one person I have met wearing a facemask explained to me that it helps keep hands away from the nose and mouth. We all “know” now that influenza is spread mostly through indirect contact.

And yet, the nation’s top experts humbly surmise that we don’t know. The website of the Canadian Medical Association Journal recently published a news item entitled “Conflict emerges over value of hand-washing as a preventive flu transmission measure” and quoted Dr. Donald Low, Microbiologist-in-Chief at Mount Sinai Hospital in Toronto, dismissing the evidence for the current hand hygiene recommendations.

Dr. Low earlier chaired a panel of top experts for the Council of Canadian Academies. Their report on influenza transmission states: “The current weight of evidence suggests that transmission of influenza by inhalation is more probable than by indirect contact” and “The panel concludes that although the occurrence and relative importance of the contact route for influenza transmission have not been demonstrated, or indeed studied in humans, contact transmission likely occurs.” In sum, it is possible that wearing (good) masks trumps washing hands.

Ponder for a moment a single word in the quote above: the most important element of the science of influenza has still yet to be studied. How is this possible? Did the medical establishment forget to study the transmission of flu? Probably not – the experts readily know that they don’t know. Is it too hard to study? Probably not, medical science is very advanced now and most of the relevant data is decades old. By elimination, it seems we need to look at the culture of science and the incentives driving scientific research.

Perhaps this type of research is too old-fashioned to be of interest to our top researchers. Perhaps it does not fit into a culture of apprenticeship where students want to learn the latest methods and instruments in order to secure a job at the end of an expensive education. I don’t know the answer, but I do know that an important lesson is emerging here: the humble flu virus turns out to be an important mentor telling us that we must think hard about our approach to science and education.