An article over at Science-Based Medicine (an American medical blog) by Mark Crislip alerted me to a Mexican study relevant to H1N1 vaccinations in Canada.
This latest study (and it’s published, too — imagine that) demonstrates no link between seasonal flu vaccines and the H1N1 vaccine. In fact the study showed a small protection effect of the seasonal vaccine against H1N1 infection. Whaaaaat?
This runs contrary to a policy-changing, vaccine schedule-convoluting, unpublished, non-peer-reviewed study from Canada that suggested that the seasonal flu vaccine increases the risk of H1N1 infection (for example).
There were pro(s) and cons to the government’s decision to change the vaccination schedule based on preliminary unpublished results:
- H1N1 is bad news. Err on the side of caution and do whatever any study suggests that may help reduce the total number of infections.
- A huge decision was made based on unpublished preliminary data.
- The change wasn’t implemented across Canada because of provincial health policy, causing fear and confusion. (What’s our province doing? Why aren’t we doing the same thing as Province X? I already got vaccinated, am I in danger? Etc.)
- Some of the reasoning seemed faulty. For example, the idea that there was an increased risk of H1N1 infection because the body’s defenses were diverted for seasonal flu. Ok, let’s say that I don’t get the annual vaccine. So I’m at increased risk for the seasonal flu — maybe I get it and then I’m still at increased risk for H1N1 anyway? So why not just get vaccinated so at least I’d have one flu instead of two? I am not an infectious disease doctor, though, so I may be missing the full benefit of skipping the vaccine (if any), as suggested by the Canadian study…
Huge changes were made to the vaccination schedule based on one study. Yet there are other studies, now, showing opposite results. This situation demonstrates the problem with “policy by press release” rather than relying on a body of literature and an emerging pattern. People were not willing to wait for more information due to the risk of H1N1. But the problem is that acting on unconfirmed (and possibly false or misleading) information can be as risky as not acting at all.
With no supporting information to justify changing the status quo, it might have been better to leave well enough alone. I suppose future studies after this season can look at the infection rates across provinces to see if the different vaccination schedules had any impact.
I’m hoping that everyone who needs them has access to vaccines, can get them on time, and is not hindered by confusion. I appreciate the difficult decision that health officials had, and appreciate that they were trying to act in what they thought was the public’s best interests, but in the future I hope health policy is decided based on more concrete, or at least more widely-supported, evidence.