On the earth, there will be viruses in any corner of life. Viruses depend on other life to survive and reproduce. They are between life and non-life. They are so simple that only a piece of genetic material is left, and a protective protein shell is wrapped on the outside.
However, the impact of viruses on life on earth is far beyond imagination. In human DNA, at least 8% come from the remnants of ancient viruses. These viruses may have infected human ancestors at some point, but in the end part of their genetic material integrated into human DNA.
In addition to “modifying” organisms at the genetic level, they also affect the behavior of organisms in the short term.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Humans originated in Africa. About 15,000 years ago, humans were distributed to all land except Antarctica through migration, but what are the factors that drive human migration?
What we can think of is that as the population grows, it is forced to migrate in order to survive resources. In fact, there is another possibility-that is, to avoid infectious diseases, or sometimes to avoid viruses.
In fact, the behavior of human beings to fear and avoid infectious diseases is engraved in the bones, and sometimes we even fear those harmless things that seem to bring diseases.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Now, we have built cities to keep bad things out of the city, but we are not free from the virus, and this time Covid-19 is the best example.
If organisms have their own natural enemies, then the natural enemies of those standing at the top of the food chain are likely to be viruses, including humans of course.
In 1918, the Spanish Flu, which broke out during the First World War, swept the world in a short period of time. This was the first worldwide pandemic and the most serious one in the history of human infectious diseases.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Statistics show that the death toll from this epidemic may exceed 100 million, and the global population at that time was only 1.7 billion.
However, the death toll directly and indirectly caused by the First World War was almost 16 million, far less than the damage caused by the virus. From the perspective of lethality, it is not an exaggeration to say that the virus is the natural enemy of mankind.
We know that in addition to viruses, infectious diseases can also be caused by bacteria or fungi, but why are viruses so difficult to control?
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Why is it so hard to find antiviral drugs?
You will find that there are many drugs for bacterial infections on the market, but it is difficult to find specific drugs for viral infections. In fact, the reason is that viruses are indeed more difficult to deal with than bacteria such as microorganisms.
Bacteria are independent life forms that are structurally similar to our cells and can survive without a host organism, but they also have many characteristics that humans do not have.
Because of this, we can build antibacterial drugs based on these characteristics that we don’t have.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
For example, penicillin works because it interferes with the construction of bacterial cell walls, but no cells in the human body have cell walls, so penicillin can inhibit bacterial growth but cannot affect human cells.
Unlike bacteria, viruses cannot reproduce independently outside the host cell (“replication” may be more appropriate here), and they need to hijack the host cell as a place to survive and reproduce.
Obviously, in terms of independent viability, the virus is completely killed by bacteria, and it can even be said that the virus basically has no independent viability.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
But their relationship with the host cell makes it difficult to kill them alone and keep the host cell alive.
Because many viruses do not kill the cell directly after entering the cell, but instead enter a latent phase, where they replicate slowly inside the cell, then leak out quietly and infect other cells.
So, there are some antiviral drugs (there are antiviral drugs) that can control their infection by interfering with the replication of the virus, but unfortunately, most of the time doing so also inhibits the replication process of the host cell, in other words this The drug is also toxic to the infected.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
In fact, the more dependent a virus is on host cells, the harder it is for antiviral drugs to work.
In addition, viruses do not have a simple classification like bacteria. Different bacteria can find many similarities, but different viruses have unimaginable differences, which means that it is difficult to find a specific medicine that can deal with multiple viruses.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Do viruses have natural enemies?
In fact, using drugs to fight bacteria can only bring short-term benefits, the resistance of bacteria will continue to increase, and eventually the drugs will fail, so now the use of antibiotics has been criticized, and many people worry about creating superbugs.
Fortunately, there are some more reasonable solutions now, that is, biological control, in other words, the natural enemies of bacteria can be used to control bacterial infections.
The available “bacterial enemies” that biologists have found today are bacteriophages—actually, viruses that can infect bacteria.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
Organisms get rid of various natural enemies through evolution, but it is really difficult to get rid of viruses. In a sense, viruses are the natural enemies of all living things.
There are some viruses that can infect bacteria and inhibit the reproduction of bacteria, but they have no effect on humans. They are really natural “antibacterial drugs”, and there are basically no side effects.
So, could viral infections be handled in a similar way?
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
The simple answer is that viruses also have biological predators, but it is difficult to deal with their infection in a biologically controlled manner.
While it’s hard to call viruses life, like we said earlier, they have a protein coat and NDA, which means they’re rich in phosphorus and nitrogen, which are nutrients for many life forms.
Therefore, it has been found that many native unicellular organisms “prey” viruses, but they basically prey on the bacteriophages we mentioned earlier, maybe only these viruses are closely related to protists.
However, it is basically impossible to use protists to treat viral infections. For that reason, viruses are closely related to host cells in our bodies, rather than being exposed to predators.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
However, there is a virus that can also infect other viruses. These viruses are called virions. Virophages are the same as the phages we mentioned earlier. They use other viruses to replicate and affect the replication of other viruses.
However, it is also difficult for us to use them as antiviral drugs, because these virions only infect giant viruses, and for those viral diseases that are not very large, their virions are basically not found.
Why do human drugs kill bacteria but not viruses? Do viruses have natural enemies?
At last
Everything in the world is always interdependent. Although viruses “disguise” themselves as not even life, there are still life that will prey on them, but it is really difficult to deal with their infection, which is determined by the relationship between them and host cells of.