Virus family

  Viruses are a kind of little life that we are familiar with but unfamiliar with. Although the new crown virus is an uninvited guest, the virus is a frequent visitor in human life. A person may be infected with hundreds of viruses in their lifetime. However, except for researchers who specialize in virology research, almost no one has actually seen the virus itself. So what exactly is a virus? What is the difference between it and another invisible organism-bacteria? Next, let us visit this strange and familiar creature-the virus.
  We are small parasites
  We are extremely small stature microorganisms. Compared with the bacteria family, we are much more miniature, usually in nanometers, which is several orders of magnitude smaller than bacteria. The optical microscope for observing bacteria can’t see us at all, and we can only see our appearance with an electron microscope with a magnification of tens of thousands of times. In addition to being small, our body structure is also very simple, consisting only of protein shells and nucleic acids wrapped inside, unlike other microorganisms such as bacteria, which have cell structures such as nuclei and organelles. More importantly, we are strictly intracellular parasites. If we want to maintain our lives, we must rely on the host cell system that is infected by us. Only in the “big house” of host cells can we have enough “food” to survive and multiply. In contrast, bacteria can live independently without the host.
  My seven Regardless of eight aunt
  our family and the animal and plant kingdoms, like, rich and varied, numerous types. Generally speaking, this large family can be divided into human viruses, animal viruses, plant viruses, bacterial viruses (bacteriophages), etc. according to the type of infected host. Different viruses usually have corresponding hosts. For example, plant viruses can only infect plants but not animals. Viruses that infect lower vertebrates such as fish generally do not infect higher vertebrates such as mammals. Since humans are actually one of the higher animals, some viruses can infect both animals and humans, such as rabies virus.
  From a more professional point of view, virologists have scientifically and systematically classified the virus families according to taxonomic levels such as order, family, genus, and species according to the biological characteristics and evolutionary kinship of different virus families. There are currently more than 140 virus families, and each virus family can be divided into several virus genera and virus species in turn. Even in the same species, there are multiple different viruses. If the virus family is a large family composed of some viruses with similar characteristics, then the virus species is like a small family composed of members who are closer to each other within the large family.
  Our diversity is also manifested in form. Generally speaking, my close relatives (viruses in the same family) tend to have similar appearances. If they are not in the same family, they will have very different styles. For example, the coronavirus has a spherical shape and looks like a crown; the rabies virus belongs to the Rhabdoviridae family and looks like a bullet; the Ebola virus has a slender body, just like the ancient Chinese “Ruyi”. The T4 bacteriophage is shaped like a sci-fi, resembling a bionic spider robot.
  How we in the human body “mischievous” in
  infectious diseases is one of the major threats to human health, most of the infectious diseases is our “masterpiece.” We often adopt different “offensive methods” when invading the human body. Coronaviruses and influenza viruses mainly invade through the respiratory tract; rotavirus and norovirus are pathogens that invade through the digestive tract, which is commonly known as “disease enters the mouth”; and arboviruses such as Japanese encephalitis and dengue virus When mosquitoes bite, they will sneak into the human body; the damaged skin and mucous membranes after being bitten by a dog or scratched are the only way for the rabies virus to “attack” the human body.
  The way the virus invades the host is closely related to the way the virus spreads. Generally speaking, viruses spread through the respiratory tract have a stronger transmission capacity, and the air droplets discharged from sneezing or even speech may contain viruses. Different viruses will infect different tissues and organs after invading the human body, leading to different diseases. The new coronavirus uses the respiratory system as its main target organ, causing respiratory diseases such as coughing and pneumonia. In severe cases, breathing difficulties may occur. Some viruses mainly infect digestive organs such as the gastrointestinal tract and liver, causing digestive diseases such as diarrhea and hepatitis. The rabies virus invades the nervous system, while the cunning HIV attacks the human immune system, causing the patient’s immune function defects. Severe viruses such as Ebola virus can cause severe hemorrhagic fever after infection, which is the most terrible viral disease.
  Our nemesis, disease-resistant guard – vaccine
  if a person is suffering from a disease caused by a virus infection, take antibiotics (which is often said anti-inflammatory drugs) is no good. Antibiotics treat bacteria, and they are helpless in the face of viruses. Treatment of viral diseases requires specialized antiviral drugs. Each antiviral drug has its specific target, which aims to target the virus in the invasion of cells, replication and other infection links, thereby blocking the proliferation of the virus in the human body.
  Another guardian that can help fight the virus is a vaccine. Compared with the passive counterattack method of taking medicine after being infected with the virus, vaccine is an active defense strategy and one of the successful methods to prevent the virus. A vaccine is essentially a biological product containing certain components of a virus. Compared with real live viruses, inactivated vaccines have lost their virulence, and attenuated vaccines have weakened their virulence. When the vaccine enters the body, the virus antigen components with it can stimulate the immune system to produce specific antibodies against the virus. When a virus comes, antibodies will quickly fight to protect humans from diseases caused by virus infection.
  Refusing to consume wild animals to eliminate the source of the virus
  Wild animal consumption is the direct cause of many new virus outbreaks. In the process of hunting, domesticating, trading, and eating virus-carrying animals, the virus has achieved cross-species transmission from the animal host to humans. Take SARS as an example. The source of SARS lies in bats, but if there is no excessive consumption of wild animals, the transmission chain of “bat-civet-human” will not be formed. Although wild animals carry the virus, they are not the culprit of the disease. Game lovers and the game trade spawned by it are the real culprits. On the other hand, the destruction of the living environment of wild animals is also one of the reasons for the emergence of new viruses. The scope of human activities is accelerating and expanding, constantly infiltrating wild animal habitats. The original ecological barrier between humans and animals has been destroyed. The risk of human beings exposed to the wild animal host of the virus has increased, allowing the virus family to spread to humans. Free rider.