Vaccines: everyone has had them, but not everyone understands them!

First, let's understand what vaccines are. How many types of vaccines are there? A vaccine is a biological product made from various pathogenic microorganisms (bacteria, viruses, tumor cells, etc.). Vaccinations are administered. In addition, the use of bacteria or spirochetes to make a vaccine can also be called a vaccine.

In general, vaccines are divided by function into live and dead vaccines, as well as preventive and therapeutic vaccines. By tradition and custom they can be classified as live attenuated vaccines, inactivated vaccines, antitoxins, subunit vaccines (including peptide vaccines), vector vaccines, nucleic acid vaccines, and edible vaccines. Vaccines are expensive and time-consuming to develop, so whenever a new vaccine is needed to combat an epidemic, we have no choice but to trust the experts. As you know, a vaccine against SARS has not yet been created. But it has to be said that the advent of vaccines has been significant, reducing the incidence of disease, human suffering, and mortality, as well as saving on medical costs and personal financial costs.

In 1796, when smallpox was raging in Europe, Edward Jenner, the father of the vaccine, made an experiment based on the English countryside legend "If you get cowpox, you won't get smallpox". He first gave a young boy, James Phillip, cowpox and then inoculated him against smallpox after he had recovered. As a result, Philip did not contract smallpox. It was proven that cowpox could make people immune to smallpox. From there the vaccine was discovered and smallpox disappeared almost two hundred years later in 1980. (To be honest, the discovery of the vaccine was great, but it seems inhumane to experiment on children. Although consent was obtained from the parents of the children, why couldn't the adults do it? With all due respect, I ask the question. What's more, the experiment was done when Philip was healthy and scratched him to get cowpox. The success of the experiment is indeed a lasting legacy. What if it doesn't work?)

What is the principle of the vaccine? How does it work? Vaccines are active immunological agents used to prevent infectious diseases by artificially attenuating, inactivating, or genetically modifying pathogenic microorganisms (e.g. bacteria, rickettsiae, viruses, etc.). and their metabolites. The vaccine retains the properties of the disease-causing organism to stimulate the animal's immune system. When the animal is exposed to this harmless pathogen, the immune system produces certain protective substances, such as immune hormones, active physiological substances, specific antibodies, etc.

When the animal is exposed to this pathogen again, the animal's immune system follows its original memory and produces more protective substances to prevent damage from the pathogen. This generally means that you are attacked with a virus that has no offensive power. After you have produced protective substances that can fight the virus, your body will know how to respond when you actually encounter a virus that is attacking you.

Are vaccines long-lasting? This is a question that most people probably don't notice because we generally only need one vaccination or several courses of vaccines over some time. However, only some vaccines are long-lasting, while others only have a very short expiry date. For example, the rabies vaccine is only valid for six months to a year. After one year, if you are injured by a dog or cat again, you will need to be vaccinated again. (That's why the joke about being able to go around screwing dog owners for a year after the rabies vaccination. It's just a joke, and not worth it if you count the suffering of flesh and blood).

All of us (except the older generation) must have been vaccinated as children in this country because in our country there are several classes of vaccines that are free and mandatory. Although the vaccines that had to be administered may vary slightly depending on the actual situation in different provinces, they are generally the same. There are 11 Type I vaccines, including BCG (i.e. the vaccine that leaves a scar on the arm), Hepatitis B vaccine, Polio vaccine, DPT vaccine, Leprosy vaccine, Leprosy vaccine, Brain B vaccine, Epidemic B encephalitis vaccine, Epidemic B encephalitis A+C vaccine and Inactivated Hepatitis A vaccine.

In addition, there is a second category of vaccines, which require a fee and are voluntarily planted. The common ones are Oral Rotavirus Vaccine, Hepatitis A Vaccine, HIB Vaccine, Influenza Vaccine, Live Attenuated Rabies Vaccine, Epidemic Cerebrospinal Meningitis A Vaccine, Varicella Vaccine, Pneumococcal Polysaccharide Vaccine.

Are vaccines safe when they are so powerful? The answer to this question is not 100% safe. Some vaccines have side effects and there are often mild, short-lasting reactions to vaccinations, such as the BCG vaccine, which can leave scars. A proportion of people will have allergic reactions, which makes vaccination even more dangerous. However, the biggest safety issue with vaccines lies with the people who make and sell them. Any cost-saving step, whether in manufacturing, transport, or storage, can lead to safety problems. The priority group for vaccinations is children and vaccinations should not be given carelessly. Always go to a proper hospital for vaccinations. When you need to buy vaccines, you should also go to a regular CDC or another place.

I think it is a summary of the main points:

1. Vaccines are biological products made from various pathogenic microorganisms (bacteria, viruses, tumor cells, etc.). Vaccinations are administered.

2. Vaccines are generally divided by function into live and dead vaccines, as well as preventive and therapeutic vaccines. By tradition and custom they can be divided into live attenuated vaccines, inactivated vaccines, antitoxins, subunit vaccines (including peptide vaccines), vector vaccines, nucleic acid vaccines, and edible vaccines.

3. The advent of vaccines has been significant in reducing the incidence of disease, human suffering, and mortality, as well as saving on medical costs and personal financial costs.

4. Edward Kinner, the father of the vaccine, customized the experiment based on an English country legend. First, he inoculated a young boy, James Philip, with cowpox and waited for a cure, then he inoculated him with smallpox. Finally, he found that Philip did not contract smallpox. A vaccine was discovered.

5. A vaccine is a non-aggressive virus that causes the body to produce antibodies and thus gain resistance.

6. Not all vaccines are long-acting.

7. There are 11 free vaccines of the first type in China. In addition, there is a second category of vaccines that are voluntary and self-funded.

8. Vaccines are not 100% safe and there are side effects, but most are only mild and short-lasting reactions. Be sure to go to a proper hospital to buy and administer the vaccine.