Dude, where’s my flu?

I’ve written about this elsewhere on social media, but decided to create a blog post for it so I can just refer to it rather than writing it all out as needed. A stitch in time and all that.

A common question I’ve heard from some Qonion is what happened to the flu? I’m not entirely sure of why they are asking this, but my best guess is that they are trying to dismiss a lot of persons listed as being covid-19 positive and/or in the hospital or dying are not actually sick with covid-19 but actually just have the flu. To that degree it is a sister to the Qonion refrain that covid-19 is no more serious than the flu (actually, covid-19 is much more serious than the flu).

They seem to be focused on the absence of reporting on influenza cases, or the apparent reduction in influenza cases compared to pre-covid-19. So I thought I’d clarify a few things that you can keep in mind whenever you hear or come across this argument.

Flu Season

It’s not flu season in Bermuda yet. Flu season in Bermuda is roughly in line with the US flu season, generally October to May, with peaks in December through to February. As such, those raising the question about the lack of flu cases before October can easily be answered by pointing out that it’s not flu season, so hardly a surprise that there’s no flu cases. Not that you can’t get flu outside of the flu season, it’s just much less likely. Having said that, October is coming up, so you would expect to see public health messaging soon with a focus on encouraging people to get the flu shot. Not only is this to reduce the risk of illness and death from the flu in general, but as we’re still dealing with covid-19 for the foreseeable future, there is a strong public health desire to reduce the overall strain on our healthcare system. In general, flu shots are available in Bermuda from late September on, and I encourage readers to take advantage of their availability.

Public Health Precautions Work On Flu Too!

It is true that the world, and Bermuda, has seen a large decline in flu cases from March 2020 to the present, in both hemispheres (flu season in the southern hemisphere is roughly May to October). This is quite easily, simply and logically explained by pointing out that the same public health measures taken to deal with covid-19 are the same public health measures that would also deal with the flu. Namely, wearing of masks, handwashing, hand sanitizing, social distancing, lockdowns and remote working, as well as reduced travel. The same measures used to reduce the rate of covid-19 transmission also reduce the rate of influenza transmission. What was novel since March 2020 was that the seriousness of covid-19 meant we collectively really ratcheted up these public health measures. If we were to regularly wear masks, remote work, reduce travel and clean our hands regularly for flu outbreaks, we would have seen much smaller flue outbreaks pre-covid-19. No one at all should be surprised whatsoever that rates of influenza were greatly reduced in both 2020 and 2021 (so far). Reduced international travel is certainly a key role in this – remember the flu season in the North is October to May and in the South it’s May to October. What happens is when the environmental conditions for flu disappear in one hemisphere it keeps going in the other hemisphere. When you remove or greatly reduce travel between hemispheres, you sort of create a circuit breaker for flu transmission in general.

Flu Shots!

In 2020 there was a lot of public health resources invested in increasing the uptake of flu shots. I haven’t seen the exact rates for Bermuda, but it’s likely our rates followed that of the UK and the USA. The reason for this increased push to get people to take the flu shot? Covid-19. Basically, the covid-19 vaccines were not readily available at that point and from a public health perspective there was a fear of a second and even a third wave of covid-19 during the flu season, and the combination of a health system already struggling to deal with covid-19 cases also having to deal with flu cases, as well as the potential for persons to suffer from both covid-19 and the flu at the same time, wasn’t exactly a rosy picture (and indeed, our second and third covid-19 wave occurred during regular flu season). So from the public health perspective it made complete sense to push the existing flu vaccines to greatly reduce the influenza part of that threat equation. The flu shots are pretty effective for the flu – about 40% to 60% effective in reducing risk of flu illness. As a result, through a combination of higher than normal flu vaccination rates and the public health precautions in place for covid-19, that also work for the flu (see above), it’s absolutely not surprising that flu rates would have been less in 2020-2021 to date than previous years.

Schools

School children play a major role in flu outbreaks, and flu season in general. As a result of covid-19 we have seen a lot of schools go to remote learning, and when able to do in-person learning they were applying covid-19 precautions (social distancing, handwashing, hand sanitizing, regular cleaning of facilities, masks, etc.). The result was to largely remove schools from the equation of flu outbreaks, meaning greatly reducing their role in the 2020-2021 flu season.

Less Flu Post Covid-19 Easily Explained

Quite frankly, that we have collectively seen less flu since covid-19 really hit the West in March 2020 is easily explainable. You just need to reflect on it and it’s easy to understand why flu rates were down. There’s no conspiracy involved – just simple cause and effect, in this case, actions as a result of covid-19 had the side-effect of also reducing flu rates.

The Sting In The Tail – The Flu Strikes Back?

Having addressed why flu rates have been down since covid-19 hit our shores it is useful now to turn to the question of what happens next? And there we come to some potentially bad news…

With less influenza variants around due to the reduced flu season (thanks to the reasons above), this does mean that there has been less potential for mutations (the opposite is the case with covid-19, which is why we’re seeing successive waves of variants). This means it is theoretically easier for the 2021-2022 flu vaccine to be more effective than usual. Which is good. The flip side however is that due to the reduced flu season, less people than normal have encountered the flu, meaning our collective immune system is a bit rusty with this annual virus. Which means we are potentially at risk of seeing a particularly bad flu season, a sort of revenge of the flu, simply because our immune systems are less ready for the flu than we would be normally.

This can, of course, be largely headed off if a large number of the community takes advantage of the flu shots. The flu shots give our immune system the heads up they need to prepare. The challenge is that those who didn’t take the flu shot last year are more vulnerable to the flu this year, so if anything we need to see an increase in flu vaccination rates for the 2021-2022 flu season – a tall order, considering last year saw an abnormal uptake and since then the anti-vaxxers have come front and center into public health debates.

My prediction? Well, I feel we’re in line for a very bad flu season. And I feel we are at risk of the ‘twindemic’ of both a covid-19 wave and flu season peaks coinciding. Those most vulnerable to a future covid-19 wave in the midst of the upcoming flu season remains the unvaccinated persons, however the threat of our hospital being overwhelmed like it is currently while also having to deal with an unusually bad flu season is high.

All I can say is I hope I’m wrong. Both on the 2021-2022 flu season being bad and on successive covid-19 waves during the upcoming flu season. Myself, I’m not going to take any chances, and I encourage readers to take advantage of the soon to be available flu shots.

8Andrew Starling, Marilyn Starling and 6 others2 commentsLikeCommentShare

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s