As of now (November 27, 2020) , new coronary pneumonia has caused more than 60 million infections worldwide and more than 1.43 million deaths, and it is still increasing at a rapid rate of hundreds of thousands of confirmed cases every day.
The development and marketing progress of the new crown vaccine is crucial to the prevention and control of the new crown epidemic. There are currently 164 preclinical studies, 37 of which have entered phase 1 clinical trials, 17 have entered phase 2 clinical trials, and 13 have entered phase 3 clinical trials , Z19z 6 vaccines have been approved for restricted use, these 6 vaccines are all in Russia and China . No new crown vaccine has been officially approved for use.
This summer, computational biologist Luke Hutchison voluntarily participated in clinical trials of the COVID-19 mRNA vaccine developed by Moderna.
However, after receiving the second injection, the injection site of his arm swelled to the size of a "goose egg". Because of the double-blind test, he was not sure whether he injected the vaccine or the placebo, but after a few hours, The 43-year-old who was originally in good health began to experience bone and muscle soreness , and 38.9°C fever . His body felt hot and cold, and he began to tremble. He sat by the phone all night, considering whether he needed to call an ambulance. Fortunately, after 12 hours, these symptoms disappeared, but he said that before receiving the vaccination, no one at reminded him that he might have such serious side effects .
vaccinologist Deborah Fuller of the University of Washington said that although the side effects of the vaccine will not cause long-term problems, what will the public think once they learn about it? She is worried that the side effects of the vaccine will make the public hesitate about vaccination.
In the past week, good news about the coronavirus vaccine has continued. Moderna, as well as Pfizer and BioNTech have announced that their mRNA vaccine has reached 95% efficacy in clinical trials in thousands of people. Moreover, these tests did not show serious safety hazards.
These two mRNA vaccines both contain a small piece of genetic code, which guides the synthesis of the spike protein of the coronavirus and is delivered through tiny liposomes composed of lipid nanoparticles. Some researchers suspect that the human immune system produces an immune response to the delivery vehicle of this lipid nanoparticle, which leads to short-term side effects .
mRNA COVID-19 vaccine delivered based on lipid nanoparticles
Vaccinologist at Mount Sinai Icahn School of Medicine Florian Krammer participated in the Pfizer COVID-19 clinical trial. He said that these short-term side effects of should not stop people. Vaccination , from the current data, the mortality rate of patients with new coronary pneumonia is at least 0.5%. Although side effects such as arm soreness, fever and fatigue after vaccination are uncomfortable, they are not dangerous.
In fact, most people vaccinated have no observable side effects. According to statistics, after vaccinated by Pfizer and Moderna, 2% of vaccinators will have a severe fever of 39°C to 40°C . Although the proportion of
2% is not high, if these two new crown vaccines are approved by the regulatory authorities, their goal is to provide vaccination to 35 million people around the world by the end of December, and will have a severe fever at 2%. It is 700,000 people .
In addition to fever , other short-term side effects may beWill affect more people. The independent committee that conducted an interim analysis of Moderna's large clinical trial found that serious side effects include: fatigue, (9.7%), , muscle pain, (8.9%), , joint pain, (5.2%), , and headache. (4.5%) .
In Pfizer/BioNTech vaccine clinical trials, the proportion of side effects is even lower. Serious side effects include: fatigue (3.8%) and headache (2%) .
The proportion of these side effects is obviously much higher than that of most flu vaccines, and it is beyond the scope of people's habits.
University of Pennsylvania vaccine expert Bernice Hausman said that transparency is the key ! Vaccine developers need to inform the public that after vaccination, side effects such as fever will occur, but such side effects are short-lived. In addition, it is necessary to provide further support for those with serious side effects, such as providing telephone guidance, and determining whether it is serious enough to go to the hospital for treatment, whether it is able to cover the medical expenses, etc. Both
Moderna's new crown mRNA vaccine and Pfizer/BioNTech's new crown mRNA vaccine require two doses, with a few weeks between them. Usually the reactogenicity is higher after the second injection. This "side effect" of just means that the vaccine works well . It shows that the vaccinators have a very good immune response to the first dose of vaccine and it has begun to work. The
researchers said that now has reason to suspect that it is the lipid nanoparticles that deliver mRNA vaccines that cause reactogenicity, which causes side effects , because lipid nanoparticles without mRNA cause the same side effects in animals , Observed the production of inflammatory mediators in muscles, causing swelling, fever, flu-like symptoms, etc.
Reference materials:
https://science.sciencemag.org/content/370/6520/1022
