Facts, figures, history and cool science

Yeah, we are supposed to be a bunch of old codgers on this site (not!), but I doubt there are too many of our members that were around during the great 1918 flu epidemic.  Certainly none that were old enough to remember what happened.  I have been reading some fascinating accounts of this pivotal era in our history and I thought I would share my insights with you.  You know what they say, you either learn from history or you repeat the same mistakes over and over.

Lessons from history

The great flu pandemic of 1918 killed anywhere from 20- 40 million people world wide. That is more people than got killed in World War I, more people than the “Black Death” (bubonic plague) killed over a 4 year period (1347 – 1351).  The impact of the 1918 flu was so stark that for the first time in ‘recent’ history the average life span in the US decreased by 10 years!

Roughly a third of the world population got infected.   Back then human population was around 1.5 billion, give or take.  We are now at four times that number, at roughly 6 billion. The 1918 flu was spread from country to country by troop movements during WWI. Today we don’t think twice about getting on a plane to go some place. Back then we had few anti-viral medications and sketchy understanding of what was going on.  Today we are dealing with a worldwide financial meltdown.  Hospitals have been cutting bed capacity for years in order to improve bottom line profits and few can handle a surge in demand.  There is chronic nursing shortage and just-in-time manufacture as well as outsourcing means we live on the edge a lot more than we used to.  Back then people were more self-reliant, more willing to work together as close knit communities.  Today we live from paycheck to paycheck, no resources of money, food or much of anything else set aside for a rainy day.  As for close knit communities, most of us now consider ourselves lucky to have cyber friends that we do not have to meet face-to-face.

“One physician writes that patients with seemingly ordinary influenza would rapidly “develop the most viscous type of pneumonia that has ever been seen” and later when cyanosis appeared in the patients, “it is simply a struggle for air until they suffocate,” (Grist, 1979). Another physician recalls that the influenza patients “died struggling to clear their airways of a blood-tinged froth that sometimes gushed from their nose and mouth,” (Starr, 1976). The physicians of the time were helpless against this powerful agent of influenza. In 1918 children would skip rope to the rhyme (Crawford)”

I had a little bird,
Its name was Enza.
I opened the window,
And in-flu-enza.

Who was most at risk?

Looking back, scientists now understand that when the 1918 flu struck very few people had any kind of immunity to this brand new flu virus.  As in any “unknown” situation, our immune systems sensed grave danger and struck back will all guns blazing.  Below is the citation for one of the most important papers on the subject.

1918 Influenza: the Mother of All Pandemics

Jeffery K. Taubenberger* and David M. Morens†
*Armed Forces Institute of Pathology, Rockville, Maryland, USA; and †National Institutes of Health, Bethesda, Maryland, USA

Younger people in the prime of their lives have stronger immune systems.  When their immune systems went into over-drive trying to fight a virus they have never seen before, much of the damage was done by the “cytokine storm” unleashed by the patients’ own immune systems.  Their lungs became a bloody pulp as a result of their own immune systems behaving like Keystone Cops on steroids, shooting first and asking questions later.

Does this mean old geezers like us have a get-out-of-jail-free card?

Not on your life!

Below is a diagram I got from the Taubenberger  paper. The dotted line is generic annual flu mortality, number of people who died in each age group (death per 100,000 persons).  As you can see, the very young and the very old were most at risk of flu related death. We have a “U” shaped graph.

Now let us look at the solid line, the mortality rates observed during the 1918 flu.  We have a “W” shaped graph.  The very young and the very old still died at the highest rates. The difference is that during the 1918 pandemic there was a clear bump in the graph representing a much higher than normal rate of death in the 14 -45 year age group. The pandemic graph is “W” shaped.

Take home lesson is this for us:  the very young, the very old, the sick and the frail are still at risk. And I want to highlight this point: the majority of the deaths were due to overwhelming pneumonia.  If you have CLL, COPD, asthma, bronchitis or any other chronic pulmonary health issue, you are automatically in the high risk group. No kidding. As I have written dozens of times, the single biggest vulnerability for CLL patients is pneumonia – viral or bacterial.

Are we done with the “Swine flu”?

Not quite yet, according to the experts.

My crystal ball is no better than yours, I have no idea whether the present behavior of the H1N1 virus (Swine flu) will continue for a while longer and then fade away.  It seems to be very communicable, it has no problem with human-to-human transmission, but the fatality rate is reassuringly low. If it stays that way into the future and gradually fades into the background, we can count ourselves lucky and go on with life.

But let us take a look again at history to see what else can happen. Below is another telling picture from the Taubenberger  paper. The first wave of the new flu struck in the spring of 1918.  It was no big deal, a mere blip in the mortality rates.  Through March – August of 1918 it spread unevenly through USA, Europe, and Asia.  Many people got infected but death rates were not that different from normal.

But starting in September through November a second (and in some countries a third) wave of flu infections / death struck.  This time there was no mercy.  Look how high the death rate was in the second wave!  So many people died so quickly that all resources were stretched to the breaking point. Historical accounts from those dark days talk about many people who died because there was no food, no help for routine illnesses, general lack of resources that we take granted in a civil society.

You tell me:  how well do you think our present day society will do if all of our resources of modern day living dry up quickly?  I think we got a taste of it in this country when bad storms devastated much of the coastline of Louisiana and other Gulf Coast states, even though the rest of the country was untouched.  How much worse will it be when the whole country, the whole world is involved in the same crisis, when there is no one left to come galloping to our rescue?  People stuck in Miami highrise apartments for just a few hours during the hurricane season because electricity went out and elevators did not work complained about lack of food and water.  One old lady said all she had to eat in the apartment was a small bag of jelly beans. How many of you fall into the same group of ill-prepared folks?

Know your enemy

Here is some cool science that you can use to dazzle your kids and neighbors.

Influenza is fundamentally a bird disease, spread through out the world because wild birds migrate long distances to distant lands. The “avian flu or H5N1 of a couple of years ago is one such bird flu disease.  Fortunately for us, flu viruses that are good at infecting birds are not very good at infecting humans.  Reason for this is very simple.  Birds have hotter body temperatures than humans, bird flu viruses have a hard time adapting to our colder noses and pulmonary tracts.

Avian flu beaten by cold noses

By Clive Cookson

An important reason why avian flu viruses rarely infect people is that the human nose is too cold, according to an analysis by virologists at Imperial College London and the University of North Carolina. This may explain why the feared H5N1 avian virus has not spread readily between people, unlike the H1N1 pig virus, which recently emerged in Mexico.

The study, published in the journal PLoS Pathogens , shows that normal bird flu viruses do not spread extensively in cells at 32°C, the temperature inside the human nose – probably because they usually infect the guts of birds, which are much warmer at 40°C. The first site of infection in humans is usually the nose, where a virus would not be able to grow and spread between cells.

Pigs are a different matter

Humans and pigs share a lot of genetic traits – one reason why it is possible to use heart valves from pigs in humans with little risk of rejection.  But the flip side of that is diseases in pigs also infect humans with relative ease. One of the common features of the 1918 flu and today’s H1N1 swine flu:  both viruses seem able to infect pigs and humans with ease.

Many researches believe pigs are the perfect promiscuous mixing vessels since they are infected with ease by human, bird and pig viruses. Pigs represent nature’s own experiments in genetic engineering, mix-and-match of viral bits to see what works.  Intensive farming practices with ever closer contact between pig herds, domesticated and wild birds and human populations has made this a much bigger concern.

What’s with the H and N?

Flu strains are named for the H and N proteins, hemagglutinin and neuraminidase, which stick out from the surface of the virus like spikes.

The name hemagglutinin refers to the ability of influenza to clump (“agglutinate”) red blood cells. A typical flu virus is covered with 500 or more  hemagglutinin molecules, which together can glue many red blood cells together into a visible clump.  But the major role of hemagglutinin spikes is that they allow the flu particle to attache to sialic acid and other receptors on cells of our respiratory tracts where it replicates like crazy and causes havoc. There are three distinct types of  haemagglutinin molecules important in human infections designated as H1, H2, and H3.

While the H spikes allow the flu virus to attach itself and penetrate your hapless cells, the N (“neuraminidase”) spikes have a different function.  You see, viruses are very simple things, they do not have the machinery to replicate themselves.  For that they have to depend on the resources of the cell they infect.  Once inside a host cell, the virus takes over the machinery of its victim and uses it to make zillions of copies of itself.  Pretty soon the victim cell is completely eaten up from the inside.

Now the virus needs to get out of the bankrupt cell.  The neuraminidase spike is used to rupture and escape the infected cell, finishing the job of killing it in the process.  Typical flu viruses have 100 or more N spikes on their surfaces.  Recorded history has shown human flu types using two types of N spikes, the N1 and N2.  But there are many more N and H types out there in nature, especially among birds.  Witness the H1N5 bird flu strain that caused a ruckus couple of years ago.

WHO chief warns against false security about flu

Citizen’s Guide to Flu Preparedness

I will end with this quote I read somewhere: Life is not measured by the number of breaths we take, but by the moments that take our breath away.