Although it has been tested in humans, the anti-Covid-19 vaccine is far from universal.
On the morning of March 17 (Vietnam time), four out of 45 volunteers in the United States received the first shot of a new vaccine against corona virus. The vaccine test took place 65 days after Chinese scientists shared data on the genome of the new corona virus, the causative agent of Covid-19 disease.
What is a vaccine?
Vaccination is a method of prevention, using the human immune system itself to fight infectious pathogens such as bacteria or viruses. According to the World Health Organization website, the vaccine is “one of the most effective ways to combat the disease”.
The human immune system has a very effective natural defense mechanism. Immune cells or white blood cells can detect and kill foreign viruses and bacteria. In most cases, the immune system can “remember” these intruders and form antibodies to fight them later.
The vaccine is a less dangerous copy of the pathogen. They cause the body to think that the body has been infected with a virus or infection, boosting the immune system to fight those threats. For example, the measles vaccine makes the body think it has been exposed to measles. When you are vaccinated against measles, your body makes a record of the measles virus. If you come into contact with the measles virus in the future, your body’s immune system is already primed and ready to defeat it before you can get sick.
The first vaccine was created by English scientist Edward Jenner in the late 18th century. He tapped from a milkman who had cowpox – a viral illness very similar to smallpox – and injected pus. people a boy. This boy had a mild fever and also had mild cowpox, but later became immune to smallpox.
The injection of pus helped the boy’s body to recognize the virus, and because the virus resembled smallpox, then his body fought the virus on its own and was not infected.
Today, it is clear that we no longer inject pus of infected people into the body. Vaccine is strictly controlled by safety standards, undergoes strict testing and governments have clear instructions for use.
What is in the vaccine?
The vaccine has many components, but generally has the main components of antigens, excipients and preservatives.
Antigen is the most important ingredient, helping the body to recognize this is an intrusive ingredient. Depending on the vaccine, the antigen may be a virus molecule such as a DNA or protein chain, or it may be a weakened living virus. For example, the measles vaccine contains measles virus that has been intervened to reduce virulence.
When the body is vaccinated against measles vaccine, the immune system recognizes the measles virus’s protein sequence and seeks to make antibodies to eliminate it.
Excipients are substances that help amplify the immune response to the antigen. The vaccine may or may not be excipient, depending on the vaccine.
Some vaccines are contained in tubes that can be used over and over, so preservatives must be included to ensure they can be kept for a long time without fear of bacteria invading. One of the most concerned preservatives is thimerosal, because it contains the mercury ethylmercury compound. According to the CDC website, the mercury compound in thimerosal is not harmful to the body.
However, the use of disposable syringes is increasingly common. These tubes will not need preservatives like thimerosal.
How to get Covid-19 vaccine?
To make an effective vaccine for SARS-CoV-2 virus, scientists must find an antigen that can induce an immune response to the virus.
SARS-CoV-2 belongs to the corona virus, and has a crown-like design. These spikes make it easier for viruses to invade body cells and multiply themselves. The scientists analyzed these spines and suggested that they could serve as antigens for any corona virus vaccine.
Protein spikes (also known as S proteins) are also characteristics of human corona viruses that have been encountered in the past such as the one that caused SARS in 2003. This has helped researchers begin to develop vaccines against partially S. protein By using animal models, they have shown that they can induce an immune response.
Many companies around the world are working on the SARS-CoV-2 vaccine, developing various ways to stimulate the immune system. A well-known method uses a relatively novel vaccine called a “nucleic acid vaccine”. These vaccines basically contain a small genetic code that acts as an antigen.
Some companies like Moderna can quickly create vaccines by combining genetic codes in the S protein with fat molecules and injecting them into the body. The Royal University of London created a vaccine from RNA, the genetic code for the virus. Inovio in the US creates DNA sequences to stimulate an immune response.
Other organizations are testing adjuvants to amplify the immune system’s response. According to the Harvard Gazette , this is a way to work towards the elderly, the immune system has no longer responded effectively to the vaccine.
When will the vaccine become available?
Anthony Fauci, director of the NIH Institute of Allergy and Infectious Diseases, said it would still take another 12-18 months for the vaccine to be fully available. This is still a record speed, as the human test took place just 65 days after Chinese scientists shared data on the genome of the new strain of corona virus.
Why does it take so long to produce a mass vaccine? Not only has it gone through many stages, the vaccine has to meet strict standards.
“Any drug sold must go through a standard clinical trial that involves one to three steps. We need to ensure that the drug is safe, will not harm and know its effectiveness,” Bruce Thompson , said the dean of medicine at Swinburne University, Australia.
Scientists cannot assume the vaccine will respond well, but they have to test it many times with thousands of volunteers. The vaccine development process can be divided into 6 stages:
– Vaccine design: studying pathogens and deciding how to create antigens that stimulate the immune system.
– Animal testing: The vaccine will be tested on animals to ensure that it has an effect on animals and that there are no dangerous side effects.
– Step 1 clinical trial: this is the first step in human testing to check the safety, dosage and side effects of the vaccine. This process only requires a small number of testers.
– Step 2 clinical trial: scientists must analyze the effects of the vaccine on the human body more closely. They have to test a large number of patients and analyze the physiological reactions of the body.
– Clinical trial step 3: at this step the number of patients participating in the trial will be more, the test time is longer.
– Licensing: Pharmaceutical regulatory authorities such as the US FDA or the European EMA will study test results and conclude whether the drug is safe for mass licensing.
Typically, it can take more than 10 years to create a vaccine. Once the licensing process is complete, the new pharmaceutical company can produce the vaccine in bulk.
With the SARS-CoV-2 vaccine, according to STATnews, Moderna has moved from a vaccine design step straight to a clinical trial step 1, ignoring animal testing.
Is there any other way to treat Covid-19?
Besides vaccines, patients with Covid-19 will be hospitalized with a treatment regimen suitable to the condition. When a person has pneumonia and affects their ability to breathe, they can be put on a ventilator, or treated with fairly birth to treat other bacterial infections. Antibiotics are used to kill bacteria, so they will not kill viruses.
Certain other medications can also disable viruses like Remdesivir. Although this drug has not been approved for mass use, it has been clinically tested. Remdesivir has the ability to remove the RNA polymerase sequence that the virus uses to clone. Therefore, this drug can be used for many different viruses, not just for SARS-CoV-2.
China also uses many other drugs for treatment, including anti-HIV drugs. Some Australian researchers also used anti-malarial drug called Chloroquine for Covid-19 patients and said it worked. In general, these drugs are inhibited, making the virus unable to replicate, thereby reducing the harmful effects of the disease and possibly shortening the duration of treatment.