The Omnidemic Discussion Thread

[alert]

I have nearly posted this thread perhaps a dozen times, but finally felt the need in light of the recent announcement of an H5N6 human fatality in China:

http://www.flutrackers.com/forum/showthread.php?t=222782

Up until 2009, human infections with non-circulating influenza viruses were rare. Other than the avian H5N1 virus, I aware of only two single fatal human infections worldwide with a non-circulating influenza virus before 2003:

http://www.cdc.gov/mmwr/preview/mmwrhtml/00021592.htm ,

and the infamous 1976 swine flu scare.

Then the H7N7 virus killed a veterinarian in the Netherlands in 2003. Then we had the H1N1 pandemic in 2009. And since then, there have been fatal human infections with H3N2v, H6N1, H10N8, H7N9, and now H5N6. In addition to those, non-fatal human infections with non-circulating influenza viruses of subtypes H1N1 (multiple avian and swine viruses), H1N2 (swine), H3N2 (swine), H7N2 (avian), H7N3 (avian), H9N2 (avian), and H10N7 (avian) have been reported. I'm sure I'm leaving some out; I can't keep track of them all anymore. So why is this happening? I can think of several possibilities, each worse than the last:

1. This is just the result of increased surveillance following the 2009 pandemic. Possible, but unlikely. Some of these viruses have caused clusters of fatalities. I can't imagine they would have been missed even pre-2003.

2. Humans are coming into contact with infected animals on an increased frequency. This is potentially dangerous, as it only takes one wrong reassortment to produce a pandemic, perhaps a severe one. This is precisely what happened in North America in 2009, when swine H1N1 and H3N2 viruses reassorted into the 2009 pandemic virus.

3. The 2009 H1N1 pandemic introduced a virus with avian and swine characteristics into the human population, and that virus has lent its genetic material into other pandemic candidates, increasing the risk of a follow-up pandemic. We know the H3N2v virus has the M gene from H1N1pdm09. It is not clear whether any of the latest threats carry any genetic material from this virus.

4. But there is one worse possibility, the one that I am naming this thread after. It is possible that something (perhaps a combination of #2 and #3 above?) is casing all or nearly all human, avian, and swine viruses to repeatedly reassort and recombine into every combination imaginable, and that some of these viruses are infecting humans. We know that the H7N9 virus is a reassortment of two avian viruses, an H7N9 and H9N2. There is a danger that most of these viruses could end up in the human population all at once.

A pandemic is when a single flu virus infects much of the world at one time. It comes from the Geek root "pan", meaning all. I am coining the term "omnidemic" (apologies if someone else has used this word first!) for the possible event when a large number of influenza viruses emerge into the human population at the same time, repeatedly reassorting with each other. The phenomenon would be something like what happens with bacteria in an NDM-1 infection, where the germs would be swapping genes so frequently as to be impossible to target. This would foil any attempt at a vaccine due to current methods, as the viruses would be mutating too fast. This could potentially be worse than even an H5N1 pandemic.

Is this a real risk? I can't tell.

We do know that since 1918, at least, only one or two influenza A viruses have circulated worldwide at a time. But what about before 1918? No one knows. Is it possible, that without much global travel pre-20th century, different viruses circulated in differ parts of the world, and that only globalization produced the concept of the "current seasonal" flu? If that is indeed the case, the concept of a single circulating flu might be an anomaly of the 20th century? If so, would it not be surprising, if influenza A played yet another nasty trick on humanity and produced the age of omnidemic?

Any thoughts?

 

[Vibrant62]

Re: The Omnidemic Discussion Thread

I have similar concerns, but my logic process is slightly different.

The world has an unprecedented number of humans living on it. the current global population is @7billion souls, supported by an ever increasing number of factory farmed animals (poultry, swine and cattle) living in ever closer proximity to each other. These populations are also increasing exponentially.

Real time population data here

Each speicies is able to be infected by different influenza's and put it alltogether and you have a 'viral soup' that is unprecedented, and where cross infections between species occur, there will also be an exponentially increased risk of reassortments, in line with the exponential increases in populations of both animals and humans. The vast majority of such events are evolutionary 'dead ends' and they never develop into anything. However the greater the frequency of such events, the greater the risk that a) one will be capable of infecting humans and b) humans will be in close proximity and c) the virus is able to adapt to become a pandemic rather than die out.

Now add your very valid points about pH1N1 into the mix and its capacity to infect both pigs and some birds, and humanised elements of the influenza genepool will have entered the avian genepool.

Now, the counter to this is that historically, as one novel flu strain has emerged in humans it has outcompeted existing strains, which have subsequently disappeared. pH1N1 replaced the old seasonal human H1N1 as far as I am aware, but did not displace H3N2.... so this in itself is a novel occurence.

Based on the above, and your observations, then yes. I think we are at risk of successive pandemics with short pandemic intervals as the signs are that while human flu's have historically been limited to H1, H2 and H3 virus types, H5, H6, H7 and H9 avian types may be adapting to mammals, at the very least and that the evolution of a highly avian pH1N1 may have opened pandoras box.

I am reminded of the old school biology experiments where a colony of amoeba or protozoa are given optimal levels of everything they need for division and growth, with the exception of space. Populations grow exponentially, until a critical mass is reached when a massive die off occurs.

I cannot help but wonder if humans are in a similar position right now.

 

[Giuseppe]

Re: The Omnidemic Discussion Thread

It is clear that with novel technological tools and increasing effectiveness of field use of these tools, the frequency of identification of rare influenza virus infections became higher than in the past.

China made great progress in ehancing health infrastructure and laboratory capabilities, and after recent H7N9 outbreaks the broad sensitive PCR assays made possible the detection of more avian-origin viruses infection.

It is not surpring, thus, to see all these H5N6, H6N1, H10N8 etc cases, because of the great advances in laboratory testing ability and technology, as well as the high degree of expertise from a rapidly changing society where people are reaching higher skills that in other part of the world.

The environmental resources exploitation is one of the possible reasons behind the reduction in the distance of animal-human interface, which means more chances for viruses to pass from a species to another.

But it has to be reminded that China is the crucible of a big number of avian species and their pathogens, and the very high human population density makes the region prone to pandemics.

So, I do not see all these changes under the skies, a part the massive and sometimes unbelievable advance in the Chinese society.

Perhaps, it is time to recognize how the things changed in the former Empire of Celestial Peace...

 

[Shannon Bennett]

Re: The Omnidemic Discussion Thread

Polio is on the rise, big Ebola outbreak, Japanese encephalitis, chickungunya is now in the new world, SARS, MERS, MRSA, drug resistant tuberculosis, so many new emerging diseases added to many old scourges revisiting us. People are forced into drinking unsafe water, living in squalor, moving into places that used to be rain forests and meeting strains of virus that kill. Foul air and contaminated soil add to the equation. So too do factory farms. And don't forget to add civil unrest which prevents a rapid response and, just plain human stubbornness and pride which also closes the doors to a swift resolution. Cars, trains, buses and aircraft can take an infected person a long way, in very close proximity to a great many people, before he even knows he is sick. I think that all of these diseases have always been around and even infecting people but now we know about them. What used to be a local and mostly limited outbreak now has the potential to become a pandemic. Better research, instant reporting remind us all every day about just how scary the world can be. More people, more infected, rapid transit, and drug resistance all make me nervous. We truly do live in interesting times.

 

[Giuseppe]

Re: The Omnidemic Discussion Thread

The example of chikungunya is even more interesting: in a developed nation, the vector-borne virus may be controlled quickly, as happened in Italy during 2007 autoctonous outbreak.

But if the same virus starts to infect mosquitoes in Haiti the picture may change dramatically.

The alien species of insects are invading regions never affected thus opening the way for more opportunity for spreading of vector-borne illnesses.

As said by Shannon, poverty, wars, unequalities are playing a pivotal role in the overall decreasing life expectancy in various part of the world.

A novel approach to economic and social development should be considered as a priority but it seems the major powers are much more interested in a Cold War revisiting...

 

[Vibrant62]

Re: The Omnidemic Discussion Thread

Unfortunately, I think it will take a global humanitarian disaster on an unprecedented scale to change political thinking in developed economies.

Until politicians in a developed society with a good healthcare system find that, for all modern healthcare's gains, they cannot significantly protect thier own populations from an outbreak that starts in some far flung corner of the world, nothing will change. Good people exist in the Healthcare sector in the US and UK (and probably many other countries) who do understand this, but until the politicians understand it too, it changes little. Without budget allocation to overseas aid, there is no money; without money nothing can change in the more deprived countries of the world. And it is politicians who control budgets.

Sad, but true.

 

[Shannon Bennett]

Re: The Omnidemic Discussion Thread

Vibrant, I also think it will mean a revised approach to humanitarian aid. If we want the early death rates to drop then we have to educate girls worldwide. If we can get most of the girls through the fourth grade everything changes. Adult educated women make the difference between high infant mortality, care for the elderly and protection of the environment. Educated men leave home and return only to visit their wives, impregnate them, see their children, then head back to the city. Educated women tend to stay home and take care of family and their community. When infant mortality drops so too does the birthrate. Fewer people in a family means a better chance at everything; food, shelter, water, healthcare, education...

 

[Nika]

Re: The Omnidemic Discussion Thread

we ARE in the midst of at least 2 titanic global catastrophies (Fukushima and climate change) and you can see how much these have brought nations together. the human mind is not constructed in a way to effectively mitigate these predicaments. we evolved for functional communities on the level of small tribal units. any larger than about 150 adults and we fall into dysfunction. we willingly choose sociopaths to "lead" beyond 150 adults but then have the gall to wonder why it doesnt work out well for all.

 

[JimO]

Re: The Omnidemic Discussion Thread

Personally, I believe that we are seeing the end of an era that was characterized by near elimination of most deadly infectious diseases in developed countries. Antibiotic and antiviral resistance and genetic changes to circumvent immune responses have caused us to see an overall increase in death rates from infectious diseases as compared with the period between WWII and the late 20th Century. This doesn't surprise me and I think we will ultimately return to a sort of equillibrium, so to speak, where the percentage of human deaths from infectious diseases will return to levels experienced before antibiotics and vaccines. The suite of infectious agents might be different, but the outcome will be similar. I also suspect that we will see the world's population peak in the near future and then begin to decline due to this phenomenon. I just see it as part of the cycle of life.

 

[JimO]

Re: The Omnidemic Discussion Thread

Educated men leave home and return only to visit their wives, impregnate them, see their children, then head back to the city.

Not all of us...

 

[Shannon Bennett]

Re: The Omnidemic Discussion Thread

rofl, No JIm, there are always exceptional people who make exceptional choices. :angel:

I mildly disagree with you, Nika. We would not have come this far as a species if we couldn't have figured out a way to work together at least some of the time. We do see inspiring people from time-to-time that make all the difference. Mother Therese, Mahatma Gandhi, Nelson Mandela are just three in the last century that made a huge impact. Yes, we do still have those who espouse hate and fear and, we still have people who so resent change they are willing to kidnap over 200 girls and threaten to sell them for the 'crime' of becoming educated. But, we also have people who spend hours of their time working for nothing more then helping others. We are some of those people.

No one gets paid here. No one in my community, outside of about 3 people even know who I am and what I do. The same is true for all of us who donate their time here. It is also true for people who send checks to disaster relief. Or, countless other people who donate, time, money and labor to help a stranger. We can be easily duped by smooth talking conmen. Some of us resent any change so much we make poor choices in elections. But, on the whole I truly believe we mean well. And, that despite our manifold errors as a species, we can, and usually do, overcome our stubbornness and stupidity to rectify egregious mistakes. Though often not before we suffer mightily for those errors first. I just hope that in the case of climate change we haven't waited so long we can't make enough of f change to alter the course of our 'experiment'.

 

[Vibrant62]

Re: The Omnidemic Discussion Thread

Good points everyone.

I still fear that 'neccesity is the mother of all invention' and until the necessity of equalising the opportunities for health, wealth and improving educational standards in every corner of the world is actively perceived by our leaders/ politicians/ corporations (I have to include them as they now wield more power than elected governments, right or wrong) it wont happen.

So, until the necessity arises to drive serious change, in the meantime we do what we can, as we can.

 

[Nika]

Re: The Omnidemic Discussion Thread

Im not talking about good intentions. If you think about activities that have required global cooperation one could make the case that those have always been for the prosecution of war.

We do not have effective global institutions nor effective harmonization across the globe to cope with global issues (those that require sacrifice versus gain such as in war). If we did there would be no kvetching here about the opacity of China, KSA and other countries in their disease response efforts.

I mention all of this to emphasize our human imperfections. Its not realistic to think that we will get our collective sh*t together to eradicate killer diseases, climate change, nor the completely avoidable clusterf*ck that is Fukushima. These require very serious commitment, the kind this species has not previously mounted in our time here.

 

[Shannon Bennett]

Re: The Omnidemic Discussion Thread

Alert, I failed to say this earlier but, I love your new word omnidemic. I knew instantly what it meant and was both intrigued and forced to consider the possibilities and probabilities.:tiphat:

 

[Vibrant62]

Re: The Omnidemic Discussion Thread

Nika - which is why it will take a global health catastrophe to unite the world sufficiently to take action. It is a war, just of a different kind.

Once they can see that the economics of global warming dont make sense, the world will unite behind defeating that on a war footing. the question is if it will be too late by that time. Same goes for Fukishima.

Unfortunely human foresight is not great, and uncomfortable truths will be ignored until the consequences no longer can be.

 

[alert]

Re: The Omnidemic Discussion Thread

Alert, I failed to say this earlier but, I love your new word omnidemic. I knew instantly what it meant and was both intrigued and forced to consider the possibilities and probabilities.:tiphat:

When I made the initial post here, I was referring specifically to influenza A. MERS, chikungunya, and other emerging infectious diseases do indeed post a serious threat to humanity, but they cannot reassort or recombine with circulating influenza A virus, so they should not affect the makeup of circulating flu A.

I was using the word "omnidemic" in a much more limited sense than all of you have redefined it. To me, an "omnidemic" was simply a situation in which there would no longer be such a thing as a "circulating" or "seasonal" flu because frequent reassortment between all the new emerging influenza A viruses would produce a nearly unlimited number of new, evolutionarily fit, viruses. My virology background is simply too weak to know whether or not this is a real threat, or whether something else would simply cause all the fit viruses to converge into one new flu and result in (merely) a conventional pandemic.

Obviously, for all the reasons you have also mentioned, there is also a risk of the kind of "omnidemic" you all have mentioned, where a large number of emerging diseases emerge at once. It seems we have two new threats to consider, and only one new word to use for them.

 

[alert]

Re: The Omnidemic Discussion Thread

One other thought comes to mind. Prior to 2009, we named influenza A viruses based on the city where they were first discovered. In 2009, we switched to naming them based only on their HA and NA; i.e. H7N9, H5N6.

In an omnidemic, even that naming system would fail, because there could be literally thousands of drastically different H1N1 viruses circulating (with different internal genes), the result of all the reassortments.

And any attempt to go back to the old naming system would fail, as there would be too many viruses (and each one would only last for a short time before reasserting again) to name. We might be forced to stop naming the viruses altogether. A patient would simply be diagnosed with influenza A; there would be no benefit to subtyping or sequencing the virus, except possibly to check for antiviral resistance (I can imagine both susceptible and resistant viruses would continue to circulate). The CDC wouldn't even need to check for mutations in the virus; every possible mutation would already be circulating somewhere.

Each of us might have our own personal flu virus.

 

[Vibrant62]

Re: The Omnidemic Discussion Thread

Alert - I do not believe that scenario would/ could evolve, although in a sense each of us does indeed have our own personal flu virus when we get flu, due to the high mutation rate.

As one flu type predominates (has a greater degree of competitive fitness) it tends to drown out others of a similar nature. The example here is pH1N1 replacing the old seasonal H1N1. If a new variant H1virus has a greater degree of evolutionary 'fitness' i.e. infectivity, it will likely drown out pH1N1, even if its an H1N2 or an H1N3

However if H5, H7, H6, H9 variant viruses were to complete a successful adaptation to humans, then it would be feasable for there to be new 'seasonal' strains so instead of humans having to contend with a seasonal H1 and H3 human virus, we could have a situation where we had seasonal strains which may include H1, H2, H3, H5, H6, H7, H9 type viruses or whatever. Some of these would 'crowd' out others but this assumes that all of these are able to increase adapation to become humanised viruses.

The benchmark is to examine what happens in avian and duck populations.

In these populations multiple flu strains circulate and are infectious. Ultimately, mammals (including humans) could end up in the same position. How soon? Such evolution would probably take millenia, but it would be a gradual process. We would likely see evidence of novel H strains appearing in swine populations first.

These links may shed some light on the swine influenza threats, as pigs are the bridge between avian and human flu types. If we were going to have a problem, we would likely see it in pig populations first.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC109961/

http://www.sciencedaily.com/releases/2013/05/130510180250.htm

http://www.irta.cat/en-us/RIT/Noticies/pages/CReSA_Virus_influenzaA_porcs.aspx

That said, if H7N9 becomes a fully human virus the rules may well change, as no one knows what the reassortment potential or outcomes would be if this enters the human influenza genepool.

 

[alert]

Re: The Omnidemic Discussion Thread

If one new flu virus, say H7N9, entered the human population, there are only 3 scenarios in my mind:

1. It replaces one or more existing flu strains.

2. It is less fit than all the existing flu strains, and dies out.

3. It reassorts with an existing flu strain, and the reassortant virus replaces both.

Either way, the situation in the first post does not occur. But what would happen if several new viruses enter the human population in a short time period?

It isn't clear to me what the interaction between such viruses would be. If virus A is more fit than virus B, and virus B is more fit than virus C, it does not seem clear to me that if viruses A and C were to both enter the human population, that virus A would be the one that continues to circulate. I could imagine a situation, similar to the children's game of "Rock, Paper, Scissors" where none of the emergent viruses is strong enough to drive out the rest, resulting in the continued circulation of all of them. We know that something similar happened in 1977 when the H1N1 virus was not able to drive out the H3N2 virus, but rather continued to circulate with it.

The analogy to birds is a good one. As it stands today, a large number of flu viruses currently circulate in birds without driving each other into extinction. Of course, no one is trying to vaccinate birds against all possible strains (as you would try to in an emerging human situation), but I think to some degree that scenario is the one I am envisioning could happen in humans. Flu viruses in birds are constantly swapping genetic material; that is where the H7N9 virus came from in the first place.

Given only 100 years of flu virus detections, and only a handful of emergences of new viruses into the human population (1918, 1957, 1968, 1977, 2009), I don't personally think I've seen enough evidence to rule out the scenario I described if multiple viruses emerge at once.

 

[Shannon Bennett]

Re: The Omnidemic Discussion Thread

Each of us might have our own personal flu virus

.

I wonder if my mine is specific to red hair. LOL

Alert, I agree with your last post and the possible scenarios. Although, eventually only one or two will actually dominate I suspect. Given that they are all novel to the human race, the cfr would be very high. Two novel flu virus circulating at the same time would be catastrophic. A one-two punch would leave us weakened by the first pass of virus A then weaken us even further and probably kill us with novel B. Novel C probably would never even be able to take hold for lack of victims. Only those who have an innate ability to fight off the virus would be left standing.