Why does rats and rodents have so many diseases ?

[nec209]

The rats are loaded with diseases some no cure if person gets rat bite.The rats for sone reason do not seem to get sick and immuned to most diseases .Yat the carry the diseases .

 

Yet on the other hand insects do not seem to really carry diseases it is mostly insect venom that is problem to people.

[charles brough]

The rats are loaded with diseases some no cure if person gets rat bite.The rats for sone reason do not seem to get sick and immuned to most diseases .Yat the carry the diseases .

 

Yet on the other hand insects do not seem to really carry diseases it is mostly insect venom that is problem to people.

Are you sure that rodents carry more diseases dangerous to us than other wild animals or are you just associating them with the Midieval Plague?

 

Also, flies, mosquitos and some other insects do carry diseases dangerous to us.

 

Do you read over and check your posts before you post them? You should . . .

 

Peace

[nec209]

Are you sure that rodents carry more diseases dangerous to us than other wild animals or are you just associating them with the Midieval Plague?

 

Also, flies, mosquitos and some other insects do carry diseases dangerous to us.

 

Do you read over and check your posts before you post them? You should . . .

 

Peace

 

I was talking to buddy I know and infectious diseases came up and saying human and animals are very conplex life form where fish and rodents are older life form and less conplex . And insect are very crude life form and very old.

 

Saying there be more infectious diseases in more conplex life form and new life form . Going on to say you can probably give any fish or insect a infectious diseases and nothing will happen.

 

But human and animals are more conplex life form and new and do not know how to cope with infectious diseases .

 

May be we need better immune system.

 

Also rats eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat. So they pick up loads of dieseases but their immune system is a lot lot stronger.Rats are often in sewers and places like that so they pick up loads of dieseases but their immune system is a lot lot stronger than ours so they dont get sick .But if they bite us we get sick and may die.

[Arete]

I was talking to buddy I know and infectious diseases came up and saying human and animals are very conplex life form where fish and rodents are older life form and less conplex . And insect are very crude life form and very old.

 

In short - no.

Genetically, anatomically and functionally speaking rodents and humans are similarly complex. We have anatomically largely have the same organs, mice actually have more functional genes than humans but they both share a goodly percentage of them (70~90%). It would be very hard to - in any rational, biologically founded way characterize rats and mice as less complex than humans. http://www.nature.co...-complexity-437

In a similar sense, characterizing insects as "very crude life forms" is hard to justify. Fruit flies have a smaller genome than most vertebrates and less genes, but this has little bearing on their relative complexity. Insect anatomy, behaviour and life history can and in a number of cases is more complex than most vertebrates.

 

The anthropocentric view that humans are the most complex life forms on the planet doesn't ring true in a biological sense.

 

Saying there be more infectious diseases in more conplex life form and new life form . Going on to say you can probably give any fish or insect a infectious diseases and nothing will happen.

 

But human and animals are more conplex life form and new and do not know how to cope with infectious diseases .

 

Diseases which affect fish/insects in most cases do not affect humans and vice-versa due to environmental and host specificity of the pathogen, not differences in relative complexity. I'd think any evidence that humans suffer more disease than other organisms would suffer from rather severe ascertainment bias - we know a lot more about human diseases than animal diseases.

 

 

Also rats eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat. So they pick up loads of dieseases but their immune system is a lot lot stronger.Rats are often in sewers and places like that so they pick up loads of dieseases but their immune system is a lot lot stronger than ours so they dont get sick .But if they bite us we get sick and may die.

 

Most of the famous rodent-human transmissions (bubonic plague, leptosporisis, hantavirus, etc) are a result of rodents and humans living in close contact, allowing pathogens which normally persist in rodents to transfer to human through insect vectors, contamination of human food and water with rat feces and urine, or direct contact - i.e. being bitten.

 

This doesn't necessarily have anything to do with the same diseases you will get by coming into direct contact with waste - e.g. food poisoning via salmonella. However accumulated waste provides a resource for rodents, bringing them into contact with humans and thus causing transmission of diseases between the two species.

Edited December 21, 2011 by Arete

[charles brough]

That clears up and settles that question, post and thread!

[nec209]

Diseases which affect fish/insects in most cases do not affect humans and vice-versa due to environmental and host specificity of the pathogen,

 

Can you elaborate here?

 

I'd think any evidence that humans suffer more disease than other organisms would suffer from rather severe ascertainment bias - we know a lot more about human diseases than animal diseases.

 

If you look at most medical books there are thousands of thousands of disease both infectious diseases ,autoimmune disease , cancer and other diseases even born defects that humans have.

 

Where fish and insects do not seem to have this problem . And where animals and rodents do have this problem it does not seem to be has bad has humans .

 

I think there would be alot of money for scientist to learn about these life forms and understand the process and diseases if it is the same , more or less diseases than humans.

 

I don't understand how small insects or fish so small can get sick when they are so small.

Edited December 24, 2011 by nec209

[Arete]

Can you elaborate here?

 

Host specificity - E.g. a disease might be able to infect reptiles and birds, but not mammals. Another might be able to infect mammals and not reptiles and birds. Neither group has more diseases than the other, but they contract different diseases.

 

Environmental specificity - E.g. A disease can live underwater but not above water, or vice versa. Many diseases of ornamental fish in aquaria affect only marine or only freshwater fish, due to environmental specificity of the pathogen.

 

If you look at most medical books there are thousands of thousands of disease both infectious diseases ,autoimmune disease , cancer and other diseases even born defects that humans have.

 

 

Where fish and insects do not seem to have this problem . And where animals and rodents do have this problem it does not seem to be has bad has humans .

 

How long have scientists studied human disease compared to animal disease? How many scientists study human disease compared to animal disease?

The answer is a lot longer and a lot more - which leads to ascertainment bias. For example - if I count hairs on the head of one person1 for a hour and get 3000 - then get ten people to help me count hairs on person 2 for a whole day and get 500 000 it doesn't mean person 2 is hairier than person 1 because I spent unequal amounts of time counting hairs - is that clearer?

 

I think there would be alot of money for scientist to learn about these life forms and understand the process and diseases if it is the same , more or less diseases than humans.

 

When fish and insects start investing in disease prevention, I'm sure there will be lots of money. While humans care more about humans not getting sick than fish/insects not getting sick, there will be a bias towards funding for human disease research.

 

I don't understand how small insects or fish so small can get sick when they are so small.

 

Most diseases are smaller than a cell. Once you become visible to the naked human eye, your actual size has little to no bearing on whether a disease will affect you or not.

[Greg Boyles]

I was talking to buddy I know and infectious diseases came up and saying human and animals are very conplex life form where fish and rodents are older life form and less conplex . And insect are very crude life form and very old.

 

Saying there be more infectious diseases in more conplex life form and new life form . Going on to say you can probably give any fish or insect a infectious diseases and nothing will happen.

 

But human and animals are more conplex life form and new and do not know how to cope with infectious diseases .

 

May be we need better immune system.

 

Also rats eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat. So they pick up loads of dieseases but their immune system is a lot lot stronger.Rats are often in sewers and places like that so they pick up loads of dieseases but their immune system is a lot lot stronger than ours so they dont get sick .But if they bite us we get sick and may die.

 

 

Surely it is more likely to be the case that, rather than insects carrying more diseases than rodents, more of the diseases that rodents do carry are likely to also effect us given that we are closer to them on the evolutionary tree than we are to insects.

[hypervalent_iodine]

That really doesn't make any sense. The diseases themselves are caused by infectious vectors such as bacteria or viruses, not the rats/insects themselves. Even ignoring that, how would it make sense that a disease carried by an organism closer to us evolutionarily than another would be more likely to make us sick? I'm really not following that logic.

[Arete]

That really doesn't make any sense. The diseases themselves are caused by infectious vectors such as bacteria or viruses, not the rats/insects themselves. Even ignoring that, how would it make sense that a disease carried by an organism closer to us evolutionarily than another would be more likely to make us sick? I'm really not following that logic.

 

Host specificity (the relative taxonomic range of a pathogen) is a result of co-evolution of pathogen virulence and host immunity. A pathogen affecting insects is less likely to affect humans than one evolved in rodents because of several factors. E.g. plant diseases and human diseases are almost entirely exclusive http://www.ourfood.c...pathology.html. as are the viruses affecting insects http://www.inhs.uiuc...ectviruses.html

 

1) A rodent body and a human body are considerably more similar than an insect body is to either - therefore a pathogen evolved to thrive in mammals is less likely to do so in an insect.

2) A pathogen is more likely to be able to evade a novel host's immune system if it is similar to the immune system of the host it naturally occurs in.

3) Adaptation to a novel host that is similar to the natural host requires fewer steps than a functionally distant host. E.g. I work on Trypanosoma brucei. T.b. brucei is only infectious in livestock. T.b. rhodesiense is infectious to humans. The inclusion/exclusion of a single gene is responsible for the ability of the parasite to evade the human immune system. http://journals.camb...line&aid=324617

4) Similar hosts are more likely to live in similar environments e.g. diseases affecting freshwater fish in aquaria are often distinct from those affecting marine fish.

Edited December 25, 2011 by Arete

[hypervalent_iodine]

Thank you for the clarification, Arete.

[Greg Boyles]

That really doesn't make any sense. The diseases themselves are caused by infectious vectors such as bacteria or viruses, not the rats/insects themselves. Even ignoring that, how would it make sense that a disease carried by an organism closer to us evolutionarily than another would be more likely to make us sick? I'm really not following that logic.

 

I think you have missed the point.

 

Perhaps you do not have an in depth understanding for example of how viruses infect us.

 

It may be the case that they are not always capable of gaining access to our bodies due to differences in antigenicity of our cells, their toxins do not effect us as badly due differences in our biochemistry from that of their normal hosts or that our immune system is better able to destroy them than that of their normal hosts.

 

Viruses generally infect their host cells by first binding with fairly specific proteins embeded in the cell membrane. The specificity can vary substantially from genus or species specific to order or family specific.

 

I suppose the most obvious example is influenza which severely effects both birds and mammals, but not reptiles and amphibians. Mammals and birds are more closely related than bird and reptiles.

 

Another example is foot and mouth disease which only causes severe disease in hoofed animals. It usually causes fairly minor infections in humans and other species I believe.

 

And I believe that most prion diseases are species or genus specific.

 

This is not to say that severe diseases in other species, that currently don't severely effect humans, do not have the potential to adapt to human hosts if there is sufficient interaction between the susceptible species and humans over a long enough period of time. We may be seeing the beginins of this with the Lyssa virus and Hendra virus carried by Australian fruit bats that also cause severe symptoms in horses but that don't seem to be able to be transmitted to humans except under rare and unusual circumstances.

Edited December 26, 2011 by Greg Boyles

[Arete]

Mammals and birds are more closely related than bird and reptiles.

 

Might want to double check that one...

 

[hypervalent_iodine]

Thank you Greg, Arete already clarified it for me. I will readily admit to not being a biologist, though I do have some idea of how viruses infect and sustain themselves within their host, albeit not a comprehensive one. And yes, you might want to check your facts on the phylogeny front.

[Appolinaria]

1324910401[/url]' post='647002']

Might want to double check that one...

 

 

No platypus flu please. None of those 3 categories would be safe.

[nec209]

No he is saying that if insects where like rats and eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat than insects would be like rats and have just has many dieseases .

 

Meaning gettng a spider bite or ant bite may kill a person.

 

 

Also put it an other way if person would eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything the person would be very sick and most likely die but for the most part rants their immune system is a lot stronger so can eat that stuff and not get sick.

 

Host specificity - E.g. a disease might be able to infect reptiles and birds, but not mammals. Another might be able to infect mammals and not reptiles and birds. Neither group has more diseases than the other, but they contract different diseases.

 

 

This is what I do not understand why that is the case?

 

 

When fish and insects start investing in disease prevention, I'm sure there will be lots of money. While humans care more about humans not getting sick than fish/insects not getting sick, there will be a bias towards funding for human disease research.

 

 

 

So in other words insects may have just has many disease but we do not know about it?

[Arete]

No he is saying that if insects where like rats and eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat than insects would be like rats and have just has many dieseases .

 

Plenty of insects feed on detritus - e.g. dung beetles, springtails, snails, various flies, etc. The positive association between increased diversity and abundance of pathogens and a detritic diet/habitat is at least to my knowledge, unsupported.

 

Meaning gettng a spider bite or ant bite may kill a person.

 

Poisoning via an emvenomating bite is wholly and completely unrelated to disease caused by a pathogen.

 

Also put it an other way if person would eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything the person would be very sick and most likely die but for the most part rants their immune system is a lot stronger so can eat that stuff and not get sick.

 

 

 

 

This is what I do not understand why that is the case?

 

 

I elaborated on host specificity in post. #12. Please read it.

 

 

So in other words insects may have just has many disease but we do not know about it?

 

Yes.

[Moontanman]

No he is saying that if insects where like rats and eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything they will eat than insects would be like rats and have just has many dieseases .

 

Insects do indeed eat those things.... I would venture insects eat things a rat would gag at...

 

Meaning gettng a spider bite or ant bite may kill a person.

 

Yes, some insects and arachnids can indeed bite and kill you, but ants sting, spiders bite, mosquitoes bite, it really depends on the species as to the danger to humans if any. House flies neither sting nor bite but they still spread disease and thus can kill you.

 

Also put it an other way if person would eat sewage, and everything be it garbage ,feces ,rotten food ,dead animals and other diry stuff just about anything the person would be very sick and most likely die but for the most part rants their immune system is a lot stronger so can eat that stuff and not get sick.

 

No, absolutely makes no sense in this context. Rats have evolved to eat the things they do, we have not.

 

This is what I do not understand why that is the case?

 

The further apart, in terms of evolution, a life form is from another the less likely they are to share disease organisms. Disease organisms generally co evolve along with their hosts. Many generations of close contact can allow disease organisms to cross the species barrier like influenza has in birds, swine and humans but we are responsible for that because we allowed those animals to live in close contact with us. At one time during the winter farm animals lived in the same house and room as their human care takers did. many generations of living in confined spaces together resulted in diseases like small pox, influenza, and other diseases making the jump to humans from other animals.

 

So in other words insects may have just has many disease but we do not know about it?

 

I would suggest that insects do indeed suffer from as many if not more diseases than humans or mammals but it's really not important that to us that insects die from disease other than to use those diseases against them.

[nec209]

Plenty of insects feed on detritus - e.g. dung beetles, springtails, snails, various flies, etc. The positive association between increased diversity and abundance of pathogens and a detritic diet/habitat is at least to my knowledge, unsupported.

 

So you saying that insects eat dirt ,dead human skin flakes, dead insects , dead human nails , garbage ,feces ,rotten food and other food around the house?

 

 

 

 

 

Poisoning via an emvenomating bite is wholly and completely unrelated to disease caused by a pathogen.

 

If most animals or rodents bite people they can get really sick and may die . Rats are really bad.

 

Where if insects bite people nothing happen other than some poisonous insects the same with fish.

Edited December 30, 2011 by nec209

[Moontanman]

So you saying that insects eat dirt ,dead human skin flakes, dead insects , dead human nails , garbage ,feces ,rotten food and other food around the house?

 

Some do yes...

 

If most animals or rodents bite people they can get really sick and may die . Rats are really bad.

 

No, not true, a human bite is one of the worst, a rat bite is not necessarily any worse than any other non venomous animal bite.

 

Where if insects bite people nothing happen other than some poisonous insects the same with fish.

 

Again, not true, some insect bites can be dangerous due to pathogens they carry, malaria comes to mind.... a fish bite could be serious as well if the fish has teeth capable of breaking your skin...

Edited December 30, 2011 by Moontanman

[nec209]

Some do yes...

 

 

So one should not kill spiders or ants in house

 

No, not true, a human bite is one of the worst, a rat bite is not necessarily any worse than any other non venomous animal bite.

 

I do not understand?

 

Again, not true, some insect bites can be dangerous due to pathogens they carry, malaria comes to mind.... a fish bite could be serious as well if the fish has teeth capable of breaking your skin...

 

How so ?