Question about viruses

[stvdv]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

I remember @shunyadragon wrote a little about viruses on RF. I don't know if you are a real expert, but if so, then I hope you know the answer.

NOTE:
I read on internet 2 totally different explanations. 1 claiming it takes time to get "used" to it's new host, so a virus won't get transferred to another host, just like that, and the other claiming a virus can be transferred just like that, so please only answer if you "KNOW", not just if you "know how to google". Because I do not trust "google info" so much anymore. I see too many lies and contradictions on the internet. There is bacterial warfare already for decades, so I am quite sure, that experts know exactly how all works, also with Corona, only they also know how to hide it from the public (maybe good, because viruses better not get in the hands of terrorists).

 

[mikkel_the_dane]

Well, you won't get an answer on the Internet or even if you ask a real life biologist. How? Because you still have to have trust, unless you do it yourself and that will take years of training and research.
Cross-Species Virus Transmission and the Emergence of New Epidemic Diseases
So either this is a part of the "fake news" or you can trust it as such.

With the standard you demand, you can't know anything or get an answer at all.

Regards
Mikkel

 

[exchemist]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

I remember @shunyadragon wrote a little about viruses on RF. I don't know if you are a real expert, but if so, then I hope you know the answer.

NOTE:
I read on internet 2 totally different explanations. 1 claiming it takes time to get "used" to it's new host, so a virus won't get transferred to another host, just like that, and the other claiming a virus can be transferred just like that, so please only answer if you "KNOW", not just if you "know how to google". Because I do not trust "google info" so much anymore. I see too many lies and contradictions on the internet. There is bacterial warfare already for decades, so I am quite sure, that experts know exactly how all works, also with Corona, only they also know how to hide it from the public (maybe good, because viruses better not get in the hands of terrorists).

I don't claim to specialist knowledge of this, but my understanding is that some viruses are capable of infecting more than one species of animal. For instance the current coronavirus has been shown to be able to infect domestic cats, though not dogs.

Secondly, viruses are not static: they have a tendency to mutate spontaneously. This can happen at any point, causing the virus to create new variations of itself as it goes. These variations will be under selection pressure, as with any other evolutionary process.

My understanding of how some new strains of 'flu' have previously arisen in China is via ducks, pigs and people being in close proximity, such that a duck virus can sometimes infect pigs, then mutate, while present in the pig population, into a form that can infect humans as well as pigs. Hence a new virus appears in humans, with some characteristics of the original duck virus which are likely to be unfamiliar to the human immune system.

The current coronavirus is said to resemble some bat viruses. As in the duck/pig case, an intermediate animal is thought to have been involved, presumably because bats and people don't come into contact very much.

So, returning to your question, I believe the answer is that some viruses can infect more than one species and then, due to their tendency to mutate, variations can appear that are able to go on to infect further species still.

 

[Terry Sampson]

Coronavirus Disease 2019 (COVID-19)
U.S. Centers for Disease Control and Prevention (CDC) (March 27, 2020)

Key Points

• Coronaviruses are a large family of viruses. Some cause illness in people, and others cause illness in certain types of animals.
• Coronaviruses that infect animals can sometimes be spread to people, but this is rare.
• We do not know the exact source of the current outbreak of coronavirus disease 2019 (COVID-19). The first infections were linked to a live animal market, but the virus is now primarily spreading from person to person.
• The first case of an animal testing positive for the virus in the United States was a tiger that had a respiratory illness at a zoo in New York City.
• We do not have evidence that companion animals, including pets, can spread COVID-19 to people or that they might be a source of infection in the United States.
• CDC is aware of a very small number of pets outside the United States reported external icon to be infected with the virus that causes COVID-19 after close contact with people with COVID-19.
• We do not have evidence to suggest that imported animals or animal products pose a risk for spreading the 2019 novel coronavirus in the United States.
• Further studies are needed to understand if and how different animals could be affected by COVID-19.

 

[stvdv]

Well, you won't get an answer on the Internet or even if you ask a real life biologist. How? Because you still have to have trust, unless you do it yourself and that will take years of training and research.
Cross-Species Virus Transmission and the Emergence of New Epidemic Diseases
So either this is a part of the "fake news" or you can trust it as such.

With the standard you demand, you can't know anything or get an answer at all.

Regards
Mikkel

Thanks for the reply. But you missed my point as to the trust issue

I trust someone who studied for it and shares his knowledge. If such a person shares it here on RF, then the information is first hand information
(Of course someone could pretend to "know" on RF, but that would be stupid, because if we find out (and we will), he will be known as a big liar)

If someone like me, who never studied viruses, googles the internet and find something, that is totally different, as he has not the knowledge himself, to know the difference between "truth" and "fake" information, as he is not a virologist himself.

Thanks for the link though, I did find something, that confirmed what I wanted to know, and from the context I know it was not "fake"

 

[mikkel_the_dane]

Thanks for the reply. But you missed my point as to the trust issue

I trust someone who studied for it and shares his knowledge. If such a person shares it here on RF, then the information is first hand information
(Of course someone could pretend to "know" on RF, but that would be stupid, because if we find out (and we will), he will be known as a big liar)

If someone like me, who never studied viruses, googles the internet and find something, that is totally different, as he has not the knowledge himself, to know the difference between "truth" and "fake" information, as he is not a virologist himself.

Thanks for the link though, I did find something, that confirmed what I wanted to know, and from the context I know it was not "fake"

Well, I am not an expert on anything as such in the standard sense. But I have learned a lot about how learning works and how to understand a general claim of knowledge regardless of the field.
In other words overall the world is a set of regularities and you can learn to spot claims who deviate from that.

So here is my "model" for viruses. They are not the host, they enter the host and since animals including us are fairly similar I need a good reason to accept that a virus at all can't "jump" between species.

So I look at a link as to where it is from and how it fits what I overall know about the world. Sometimes I learn something new and have to revise my knowledge. Other times it fits with what I already knew.
You did the same in effect.

Regards
Mikkel

 

[Polymath257]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

I remember @shunyadragon wrote a little about viruses on RF. I don't know if you are a real expert, but if so, then I hope you know the answer.

NOTE:
I read on internet 2 totally different explanations. 1 claiming it takes time to get "used" to it's new host, so a virus won't get transferred to another host, just like that, and the other claiming a virus can be transferred just like that, so please only answer if you "KNOW", not just if you "know how to google". Because I do not trust "google info" so much anymore. I see too many lies and contradictions on the internet. There is bacterial warfare already for decades, so I am quite sure, that experts know exactly how all works, also with Corona, only they also know how to hide it from the public (maybe good, because viruses better not get in the hands of terrorists).

First of all, there is a very wide variety of viruses. There are viruses that only infect bacteria, viruses that only infect plants, etc.

Viruses consist of some sort of genetic material (DNA or RNA) surrounded by proteins and sometimes by a lipid membrane. They enter a cell by attaching to certain 'receptors' on the cell and inducing the cell to let in the genetic material. From there, the take control over the cell's genetic machinery, forcing it to make the proteins of the virus, which spontaneously assemble to make new viruses.

Because viruses have RNA or DNA, their genetics will spontaneously mutate. Because they don't have the repair machinery that cells usually have, those mutations tend to accumulate faster. Yes, this is a type of evolution. Those viruses that lose their ability to infect, will stop doing much of anything.

Next, each 'species' of virus infects a particular type of cell, whether in the lungs, or intestines, or whatever. This is determined by the outer proteins of the virus and which receptors on which cells it can bind to. This means that if two animal species (I assume animal, but the basic idea works for plants, bacteria, etc) have basically the same type of cell and if they make a similar enough receptor, the virus will be able to infect both species of animal. This is very common. Most human infectious diseases ultimately came from animals.

Now, if the genetics of a virus mutate, this mutation can sometimes allow the virus to bind to similar cells in a new animal species. This allows a new population for the virus to spread into and, when it happens, is favored by the evolution. This is how viruses can begin to infect a new species (like humans).

So, to answer your basic questions:

Yes, it is possible for an animal virus to mutate and gain the ability to infect humans. It requires a specific mutation to allow for this, though.

Yes, it is possible for a human virus to mutate and gain the ability to infect an animal species. It requires a specific mutation to allow for this, though, and will tend to be specific to that new animal species (being able to infect cats doesn't make it able to infect dogs, for example).

Yes, it is possible to a strain of virus to infect more than one species of animal. Usually, when it does so, the species of animal are close to each other (different species of cats, for example), but not always.

It isn't a matter of 'getting used to a new host'. It is a matter of having a genetic mutation that allows it to infect a new host. How long it takes for such a mutation is highly variable. But once it happens, it will be infectious in the new host.

In general, a virus that has mutated will spread quickly to a new host because the host doesn't have immunity. It takes time for the host species to gain immunity.

 

[shunyadragon]

Well, you won't get an answer on the Internet or even if you ask a real life biologist. How? Because you still have to have trust, unless you do it yourself and that will take years of training and research.
Cross-Species Virus Transmission and the Emergence of New Epidemic Diseases
So either this is a part of the "fake news" or you can trust it as such.

With the standard you demand, you can't know anything or get an answer at all.

Regards
Mikkel

The reference provided is excellent and broadly science based with many references to research in recent years.

 

[MNoBody]

and ...if a specific virus mutates [ which they tend to be disposed to do]
then whatever 'vaccine' may have been developed to deal with it, will no longer work as the mutation makes it different enough for the 'vaccine' to be ineffective.
according to the virologists
which is the constant problem with things of this nature.

 

[Jayhawker Soule]

See CDC: If You Have Animals ...

 

[Valjean]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Viruses must gain access to a cell to do any damage. Cells have external membranes whose purpose is to let some things in and keep other things out. To get in, most viruses must have some surface structure that properly keys into locking structures on a membrane's surface. If a virus has a "key" that fits, the cell will take it in.

Cells evolve, they change. Membrane keys that exclude a particular virus, chemical or bacterium can change to admit them.
Viruses evolve, too, though their "evolution" is more a product of copying errors than reproductive variation. In any case, their "keys" can change, too -- to fit a previously unlockable key.

Often viruses that infect only a specific animal can change to access the cells of a different animal. This is how influenza came to be a human disease. It "jumped species." It originally was a bird virus that changed in a way to enable access to pig &/or human cells.

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

How long a new viral disease takes to spread depends on a lot of things: how well it can exploit a hosts cellular machinery, which cells it infects, how it's spread, population dynamics of hosts, &c. It can be fast or slow.
Virulence depends on chance genomic changes. Usually multiple changes are needed to facilitate widespread infection, so it takes several steps to become really adept at infection -- but not necessarily. A virus may chance on a really effective variation that enables rapid growth and transmission.

 

[stvdv]

@mikkel_the_dane
@exchemist
@Terry Sampson
@Polymath257
@shunyadragon
@MNoBody
@Jayhawker Soule
@Valjean

Thank you all for the your information. I try to stay 1 step ahead of Corona, and knowledge is a good step. I used to go to India every year, not taking hepatitis vaccin, and every year I got hepatitis (ca. 4 times). Finally I decided to take a vaccination, and never got it again. What a relieve. But with Corona, I better not take that chance (that one might kill me).

 

[stvdv]

and ...if a specific virus mutates [ which they tend to be disposed to do] then whatever 'vaccine' may have been developed to deal with it, will no longer work as the mutation makes it different enough for the 'vaccine' to be ineffective according to the virologists which is the constant problem with things of this nature.

So, are you saying that when they find a vaccin, it might not work anymore after some time? They need to update the "anti-virus (vaccin)" (in computers I know this to be true; did not know this also is the case for real-life viruses). My hepatitis-vaccination worked miracles for many years luckily.

 

[Daemon Sophic]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

I remember @shunyadragon wrote a little about viruses on RF. I don't know if you are a real expert, but if so, then I hope you know the answer.

NOTE:
I read on internet 2 totally different explanations. 1 claiming it takes time to get "used" to it's new host, so a virus won't get transferred to another host, just like that, and the other claiming a virus can be transferred just like that, so please only answer if you "KNOW", not just if you "know how to google". Because I do not trust "google info" so much anymore. I see too many lies and contradictions on the internet. There is bacterial warfare already for decades, so I am quite sure, that experts know exactly how all works, also with Corona, only they also know how to hide it from the public (maybe good, because viruses better not get in the hands of terrorists).

Whether you knew it or not, you have asked a very complex question with a lot of very complex steps in answering it.

@exchemist did a nice job of explaining the process here...

.....
Secondly, viruses are not static: they have a tendency to mutate spontaneously. This can happen at any point, causing the virus to create new variations of itself as it goes. These variations will be under selection pressure, as with any other evolutionary process.

My understanding of how some new strains of 'flu' have previously arisen in China is via ducks, pigs and people being in close proximity, such that a duck virus can sometimes infect pigs, then mutate, while present in the pig population, into a form that can infect humans as well as pigs. Hence a new virus appears in humans, with some characteristics of the original duck virus which are likely to be unfamiliar to the human immune system.

The current coronavirus is said to resemble some bat viruses. As in the duck/pig case, an intermediate animal is thought to have been involved, presumably because bats and people don't come into contact very much.

So, returning to your question, I believe the answer is that some viruses can infect more than one species and then, due to their tendency to mutate, variations can appear that are able to go on to infect further species still.

If I may elucidate a little further in answering the OP....
A virus, let’s say living in a bat (a mammal) is invading a cell and producing 1 million copies of itself before releasing those copies into the bats bloodstream, where it then infects tens of thousands of other cells, each one making 1 million copies.......and then millions of cells each one making another million copies apiece, etc.... This bat virus has a viral shell with very specifically shaped proteins on its surface. These proteins act like keys to interact with the proteins on bat cell surfaces. A very specific lock and key set.

Each time the virus is replicated there is a small chance of a minor mutation, many of which will kill the virus, many others will do nothing at all, and rarely one change will alter the shape of the surface key proteins.
One slight mutation might make the key work on other similarly related mammalian cells. Normally with a population of thousands of bats living alone in a cave, if one bat gets one virus that now has a key that can open human cell surface protein “locks”, then nobody cares, because eventually that bat will grow old and die without ever encountering a human; and its human-infective virus will die with the bat.
But if there is a human who loves to go to the cave and pet (or eat) the bats, then there is now a much higher chance that during this human’s normal day, being impotently assaulted by millions upon millions of bat viruses with nothing attaching to his human cells......he may now encounter that one bat with that one viral particle that actually can attach to a human cell and insert itself and multiply. He then goes home to his loving family and infects all of them in the following days. Now the spread begins in the human population with this brand new mutant bat/human evolved virus.

So @stvdv , the virus does not get into a human, and then “adapt” over time to work in humans. Rather a fluke mutation occurs within the billions of viruses in the non-human animal population. Then chance brings it close enough to a human to infect them. The mutation is rare in the extreme to make a virus able to transfer from one species to another, and it will likely just kill off that line of viruses, but it only takes minutes or hours to replicate a virus with or without this new mutation/defect.
However, if you now mix that herd/flock/swarm of non-human animals in close contact with a crowd of humans, there is a VERY small chance that EVENTUALLY one little defective ugly duckling of a virus will land on fertile human “soil” to bloom into a fully functioning human virus.
So how often do swarms of bats get a nasty virus in their population? I don’t know.
Out of all the wild bat swarms on Earth, how many are in frequent close contact with humans? I don’t know, but I’ll guess at ‘very, very few’.

 

[MNoBody]

So, are you saying that when they find a vaccin, it might not work anymore after some time? They need to update the "anti-virus" (in computers I know this to be true; did not know this also is the case for real-life viruses). My hepatitis-vaccination worked miracles for many years luckily.

apparently, so the experts in the field say, it is a worry.
....bacteria [like virus's] also mutate rendering anti-biotics useless,
look into the janitorial aspect of any hospital and see the things they now must do to combat bacteria in the building ....
cleaning compounds that need to be ever more toxic to actually get a high enough kill ratio...
most disinfectants are mostly worthless in killing the super strains of mutated bacteria......
they are almost out of chemical options completely
similar in agriculture..... pests develop resistance to the sprays to suppress or eradicate,
and the manufacturers have to make ever more virulent and toxic defenses
against an ever mutating adversary.
that, in brief, is the state of things currently.

 

[shunyadragon]

Question about viruses:

When a virus is living on an animal, is it possible it gets transferred onto a human?
When a virus is living on a human, is it possible it gets transferred onto an animal?
Are there viruses that can be transferred to multiple other beings (animals/man)?

Or is it a kind of evolution, that it takes some time, for a virus to get used to a new host?
And if it takes some time, do we speak about days, weeks, month or years?

I remember @shunyadragon wrote a little about viruses on RF. I don't know if you are a real expert, but if so, then I hope you know the answer.

NOTE:
I read on internet 2 totally different explanations. 1 claiming it takes time to get "used" to it's new host, so a virus won't get transferred to another host, just like that, and the other claiming a virus can be transferred just like that, so please only answer if you "KNOW", not just if you "know how to google". Because I do not trust "google info" so much anymore. I see too many lies and contradictions on the internet. There is bacterial warfare already for decades, so I am quite sure, that experts know exactly how all works, also with Corona, only they also know how to hide it from the public (maybe good, because viruses better not get in the hands of terrorists).

Despite his skepticism the reference @mikkel_the_dane gave is an excellent science based reference, but for some it may be a little difficult read. I liked the posts from @Polymath257 and @Valjean. I may post more in the future.

 

[stvdv]

So @stvdv , the virus does not get into a human, and then “adapt” over time to work in humans. Rather a fluke mutation occurs within the billions of viruses in the non-human animal population. Then chance brings it close enough to a human to infect them. The mutation is rare in the extreme to make a virus able to transfer from one species to another, and it will likely just kill off that line of viruses, but it only takes minutes or hours to replicate a virus with or without this new mutation/defect.
However, if you now mix that herd/flock/swarm of non-human animals in close contact with a crowd of humans, there is a VERY small chance that EVENTUALLY one little defective ugly duckling of a virus will land on fertile human “soil” to bloom into a fully functioning human virus.
So how often do swarms of bats get a nasty virus in their population? I don’t know.
Out of all the wild bat swarms on Earth, how many are in frequent close contact with humans? I don’t know, but I’ll guess at ‘very, very few’.

Thank you for your extensive explanation.
If I understand correctly, the virus always starts in animals. And because of different mutations it can happen that 1 mutation on the animal will be one that will survive on humans. But the human only "gets" it when coming in contact with that animal.

Question:
1) Do these animals also have immune systems, that will kill the viruses, so that, even if there is 1 "human mutation type" virus on the animal, that after a while this human virus will be destroyed, so that no human can get infected anymore (until a new human mutation happens)?
2) Suppose a human gets infected with this human virus, and our immune system is strong enough, will this virus then be completely killed? Or will there be a kind of balance, and the virus will stay alive (together with the human host), maybe for many years?
3) And if our immune system is not very strong, does the virus then keep on multiplying till we die. Or does it depend on the type of virus?

 

[stvdv]

I read in below article the following, which if true, is a big relieve to me. But is this true? I saw that the link in the quote did not work anymore. Bummer.

What’s the best surface for killing viruses? Our skin. In the cases of both flu and cold-causing viruses, infectious particles on our hands are usually gone after 20 minutes

Between its pH and its porous nature, our body’s natural barrier to the word does a great job at killing viruses, Greatorex explained. “Our hands are quite antimicrobial themselves,” she said. “They have their own bacteria that live on them — no matter how clean you are — and they don’t actually harbour viruses that well.”

That said, any open wounds on our skin would be an easy gateway for viral infection, so remember to use those bandages.

How long do cold and flu viruses stay contagious on public surfaces?

 

[stvdv]

Below quote from below link gives a little more hope for me:

Can You Get a Virus From a Surface?
If you touch a surface that is contaminated with a virus — including COVID-19 — does that mean you will get the virus? Not necessarily. But if you don't immediately wash your hands, and then touch your mouth, nose or eyes, you could transmit the virus. However, the CDC says surface contamination isn't considered the most likely way to get coronavirus. Without a host, viruses begin to degrade pretty quickly, so what is on the surface becomes less and less potent.
How Long Can Viruses Live on Surfaces?

 

[Polymath257]

Thank you for your extensive explanation.
If I understand correctly, the virus always starts in animals. And because of different mutations it can happen that 1 mutation on the animal will be one that will survive on humans. But the human only "gets" it when coming in contact with that animal.

Question:
1) Do these animals also have immune systems, that will kill the viruses, so that, even if there is 1 "human mutation type" virus on the animal, that after a while this human virus will be destroyed, so that no human can get infected anymore (until a new human mutation happens)?
2) Suppose a human gets infected with this human virus, and our immune system is strong enough, will this virus then be completely killed? Or will there be a kind of balance, and the virus will stay alive (together with the human host), maybe for many years?
3) And if our immune system is not very strong, does the virus then keep on multiplying till we die. Or does it depend on the type of virus?

1. Yes, animals have immune systems. And just like ours, those immune systems can be overwhelmed and/or viruses can spread from one animal to another before the immune system kills them off in that particular animal.

If a mutation would allow for human transmission, but there is no human available to infect, it will spread in the original animal population just like the normal virus would.

2. Remember that the virus has probably spread in the animal host population (it will be able to infect both that animal and humans), so if several different humans interact with that animal species, it increases the risk that someone without a strong immune system will be infected.

So, yes, it is quite possible for a virus that 'could' infect humans to be present in an animal population for many years before humans interact with it enough for it to spread into the human population.

Also, that human population may not, initially, interact much with other humans, so the virus may not spread out of one locality for a while, even after it jumps to humans.

3. That depends on the type of virus. A virus that kills too quickly is less likely to be able to infect a new person before killing the one they are in. That will limit the spread of the virus (Ebola is like this). On the other hand, a virus can be 'silent' with no obvious symptoms and spread to other people. It is quite possible for a virus to NEVER cause an illness and still spread quite widely.

If you have no immune system at all, there are many, many common diseases that will kill you. This is why immuno-compromised people have to be very careful. Even bacteria or viruses that would normally be no problem can lead to death.

For those with healthier immune systems, it will be a balance. How fast does the virus spread in the body? How fast does the immune system react? Does it over-react causing its own problems?

Sometimes, viruses can become dormant: they survive in some cells but don't infect others for long periods of time. This is usually because the immune system is keeping them in check. Herpes viruses (cold sores are a type of Herpes virus, by the way) often do this. Then, when the immune system is compromised in some way, the virus can spread again, leading to illness again. This is why Herpes has flareups and remissions.

And, of course, it is also possible that the immune system will kill off all the viruses in the host. Usually, this can lead to immunity to further infection. This depends on whether the virus mutates again in a way to avoid the immune response. Flu viruses tend to mutate a lot in this way, which is why flu vaccines tend to only work for the year they are provided.