In order to prevent disease, we have been vaccinated with various vaccines since we were born, such as BCG, hepatitis B vaccine, polio vaccine, diphtheria and tetanus vaccine, meningitis vaccine, mellitus vaccine, hand, foot and mouth vaccine, chickenpox vaccine, HPV vaccine, and the new crown vaccine that has been vaccinated in recent years.
Some people will leave scars after vaccination, but some will not; some people have "vaccine marks" on their arms, but some will not.
What's going on here? Let’s talk about the “vaccine mark” below.
"vaccine mark" comes from? There are many types of
vaccines:
1
live vaccine
is a vaccine made of live viruses or bacteria, such as the earliest smallpox vaccine. Since this type of vaccine is equivalent to an infection once, the reaction is large, this type is basically not available now.
2
Attenuated live vaccine
As the name suggests, it is to use live pathogens with weakened toxicity or very similar low-toxic pathogens. The BCG vaccine for preventing tuberculosis is a live attenuated vaccine.
3
inactivated vaccine
is to use a complete, killed (inactivated) or modified pathogen so that it cannot reproduce and will not cause diseases, such as the inactivated COVID-19 vaccine used by our country.
4
recombinant protein vaccine
is not a complete virus, and one or several important parts of the virus are composed of, such as HPV vaccine.
In addition, there are nucleic acid vaccines, polysaccharide vaccines, etc.
live virus/attenuated live virus is generally stronger than other types of vaccines. After vaccination, the body's immune response is also stronger, so it is possible to leave a "vaccine mark" at the injection site.
If BCG vaccine is used, an inflammatory reaction will occur about 3 weeks after vaccination. The vaccination area will be red and swollen, and the middle softens to form a small pustules. Then the pustules rupture, and the scab begins to form a scab 1-2 weeks after the pus is removed. Finally, the scab falls off to form a round scar, also called "scar stuck".
What kind of vaccine will leave a mark if you receive?
Although there are many types of vaccines, there are only two types that will leave a "vaccine mark" at present: smallpox vaccine (also called vaccinia vaccine) and BCG vaccine.
In May 11980, the World Health Organization announced that humans had eradicated the smallpox virus, and my country canceled the nationwide vaccination of cowpox in March 1981.
Therefore, most people born in the 1980s, 1990s and 2000s have never received vaccinated vaccination. Usually there is only one "vaccine mark" left by the BCG vaccine on their arms, and people born 80 years ago may have two scars on their arms.
Not everyone who has received the above two vaccines will definitely have a "vaccine mark". There are exceptions to scarring according to personal constitution. For example, some newborns do not have that large immune response after vaccination, and scarring may not be obvious, and the scars will gradually fade as they age, and they will basically not be visible in the end.
Why should vaccines be administered to the arm? Most of the ways to get vaccinated are intramuscular injections, that is, the injections on the arm. In addition, there are also oral treatments, such as the "sugar pill" vaccine to prevent polio virus; there are also measles vaccines that are given subcutaneously.
The arm becomes the most common part of vaccination, which is related to the following factors:
1. The fundamental purpose of a vaccine is to arouse the human body's own immune response, remember this pathogen, and fortunately, it will react quickly and eliminate it next time you meet it.
The human body's lymph nodes are a key part of the immune system. Vaccination is closer to the lymph nodes, which is more conducive to activate the immune response. Many vaccines are shot on the deltoid muscle of the arm because the deltoid muscle and the lymph nodes under the armpit are very close.
If the vaccine is injected into the thigh, it is not far from the gathering of the inguinal lymph nodes.
2. Intramuscular injection can keep the vaccine reaction locally. If it is injected on fat tissue, the redness and swelling may be more serious.
The size of the muscles also affects the choice of injection location. Children under three years old have smaller muscle tissue in the arms, so when injecting intramuscular vaccines, they are usually on the thighs close to the inguinal lymph nodes.
3. From a convenient point of view, hitting the arm is also the most convenient to operate and accept.
What should I pay attention to when I get vaccinated?
If you suffer from tuberculosis, nephritis, heart disease, immunodeficiency, etc., vaccination should be postponed, and the doctor should be asked whether you meet the vaccination conditions and re-injection at the appropriate time.
Do not eat warm or hot foods or drinks within half an hour after taking oral polio vaccine in children.
Pay attention to rest the day before vaccination, try not to stay up late, drink alcohol, eat spicy and irritating foods, and maintain the best condition of your body.
Source: Popular Science Chinese
