Monthly Archives: November 2024

News this Week

This week marked a very concerning development in H5N1. A teenager in British Colombia is the first known case of H5N1 in Canada. It’s an odd coincidence that the province is adjacent to the first US state to have had a confirmed COVID case in 2020.

There are two things about this that are the most alarming. First, the teen didn’t have any underlying medical conditions. “The teen first went to the emergency department on Nov. 2 and was tested and sent home, but returned to hospital days later when symptoms worsened” and is now in critical condition. We don’t have any details other than presumptive pneumonia, but to me that suggests that they developed acute respiratory distress syndrome (ARDS) induced by a cytokine storm.

ARDS is a serious lung condition that occurs when fluid builds up in the tiny air sacs (alveoli) in the lungs, leading to critically low oxygen levels in the blood. This condition can develop rapidly and is often associated with severe illnesses or injuries, such as sepsis, pneumonia, COVID-19, or trauma.

This is what was happening with the Spanish Flu in 1918. “British military doctors conducting autopsies on soldiers killed by this second wave of the Spanish flu described the heavy damage to the lungs as akin to the effects of chemical warfare.”

There hasn’t been an update on the teen recently, which I suspect may mean no improvement.

The second alarming thing is the results of the sequencing of the virus from the teen. One thing about H5N1 so far has been that the virus has not been easily spread person to person. However, the virus from the teen had two key changes in the hemagglutinin gene. Hemagglutinin is a protein on the surface of certain viruses, including influenza, that binds to the sialic acid receptors on cells that it will infect. Think of it as the key that unlocks the door to gain entry into the cell. Those two substitutions are known to enhance binding to mammalian receptors, ie, it makes it much more easy to infect a person.

Why this Is Important

I tweeted this almost two years ago.

We are getting very close to human-to-human transmission. That risk will increase significantly as seasonal influenza comes into play. Influenza is a very sloppy replicator and will mix its genes as well as mop up genes from the environment.

People simply do not comprehend the scale of what could happen with H5N1.

Even if we took a more conservative mortality rate of 25%, that still means 600 million deaths worldwide. For another perspective on that number, it would be like everyone in the United States (except those in Massachusetts) dying…TWICE.

Those number also are assuming that everyone infected would get good healthcare. We don’t have that capacity, so the numbers would likely be much higher.

In addition, it also doesn’t reflect the mortality related to other causes as supply chains and services are disrupted.

There is another wild card today that didn’t exist in 1918 – immunocompromised people. If cytokine storms are the result of a healthy, overactive immune system, what happens at the other end of that spectrum among those with untreated HIV or are on immunosuppressants? Does that mean that they could amplify the virus and become superspreaders? I tweeted about this as well.

The COVID pandemic should have alerted us to how fragile supply chains are, but we continue to live in denial about that. Even domestic production is no panacea in the world of climate change. This was obvious due to the shortage of IV fluids as a result of the remainder of Hurricane Helene passing over North Carolina.

We live in a world of very complex systems. The more complex a system is, the more opportunities it has for failure. This problem was addressed very well in an article by Debora Mackenzie in the New Scientist in 2008. This is the one to read if you really want to have a grasp of this threat, but it is behind a paywall. I found the text of it here as well.

If you wonder how I sleep at night, lately, not very well.

Note: CDC had changed the structure of a data file this week, which made the percentage of ED visits break in my state files. I looked at trying to fix them all, but then realized that there will likely need to be a massive data overhaul in about a week since hospitals are required to report data again. This will require a complete rebuild of the file for each state, so I decided to just wait and see what kind of data is available next week.

Epidemic curves are simply a means to represent cases or deaths over time. For example, are the deaths from the Spanish Flu from different cities. Note at the peak in NYC, the mortality rate was running about 6%.

It’s also worth pointing out there there was a small wave in late June/July which can be more easily seen here.

That’s almost reminiscent of how smaller waves preceded both the delta and omicron waves from COVID, which also disproves the claim that viruses get milder over time. It’s also worth pointing out that once rapid tests came out, that cases really don’t paint an accurate picture of the burden of COVID in the US anymore, which is why I plot wastewater, positivity, and ED visits on the site.

Another way to analyze the impact of a disease is to view deaths by age group. Normally, influenza has a U-shaped curve, with most of the deaths occurring in the very young and very elderly, as represented by the dotted line on the graph below. During the Spanish Flu pandemic, there was a w-shaped curve (solid line), with a disproportionate amount of death in the young and healthy. In this case, the likely cause was a cytokine storm driven by the virus. Those with developed, healthy immune systems were at higher risk of this outcome as the immune system over-responded to the infection. In fact, the damage was so sever that the lung tissue from those victims looks like it had been exposed to chemical weapons.

A Brief Aside about COVID Mortality

Here’s a graph of COVID acute mortality in the US. COVID deaths are undercounted for a number of reasons, contrary to minimizers claims. Yes, a few get miscategorized, but that is the exception rather than the rule.

The red line on the right is what I want to emphasize and is my expectations for the future. COVID causes MANY chronic diseases as well as immune system disruption. The line represents the climb in chronic disease deaths from these sequelae. Acute COVID deaths will likely continue their normal wave patterns (unless we get a much better vaccine) built on top of these deaths. This of it as the x-axis curving up due to chronic disease deaths. Of course, these will likely be undercounted as COVID deaths as well. This is a VERY different pattern than what we see with seasonal influenza. It can cause other problems, but that generally happens within a few months of infection, such as a rise in acute myocardial infarction deaths, which are related to the inflammatory process of influenza. COVID is different in that it causes small clots in blood vessels, leading to focal tissue damage, death, and scar tissue from oxygen starvation, which will take a number of years to manifest.

A H5N1 Curve

People will notice a very obvious difference with a H5N1 pandemic compared to COVID if it starts and maintains the mortality (25-50%) we have seen in the past. In addition, it is spread more readily than COVID because it is also spread by contact and fomites, which suggests it will be much more transmissible.

That would result in a much higher and narrower wave of death. To illustrate that in comparison to COVID, something like this would not be surprising. That will cripple healthcare instantly and will make the supply chain problems we had since the start of the pandemic look like child’s play.