Infectious disease pediatrician Anna Gorbunova told Vechernyaya Moskva about the current vaccines against coronavirus.
There are several types of vaccines - genetic, vector, recombinant, inactivated, whole viral, and protein-based vaccines. When creating the first, part of the genetic code of the coronavirus is used. They stimulate the immune system to produce antibodies.
“The advantage of these vaccines is that RNA and DNA vaccines can be obtained much faster than with traditional methods of obtaining material,” said Anna Gorbunova.
Today, the Moderna vaccine is known, the effectiveness of which exceeds 94 percent. It is administered twice with an interval of four weeks. Deals have been made with several countries to supply the vaccine prior to approval. For example, Modern has shipped 18 million doses to the United States. Previously, agreements were reached with other countries, including Canada, Japan, Qatar and South Korea.
Another genetic vaccine, Comirnaty, is 95 percent effective.
- Two injections of the drug are given three weeks apart. The expansion of Comirnaty around the world will be partly determined by the deals the companies entered into with foreign countries over the summer, Gorbunova said. - It is expected that by the end of 2021 more than 1.3 billion doses of this vaccine will be produced worldwide.
Vector vaccines work differently. They use a so-called adenovirus, which slips into cells and unloads the coronavirus gene from them.
“Since the adenovirus lacks one of its own genes, it cannot connect with others and is therefore safe,” the doctor explains. - The new vaccine against coronavirus, developed by Russian scientists, contains two vectors - two carriers, which allows you to reliably and safely get an immune response to the second dose. That is, the first dose is delivered in one vector, and the second, additional dose, in another carrier.
Adenovirus, although deprived of the properties to multiply, is still foreign to humans, therefore an immune response will be developed to it.
- To vector vaccines, not only an antibody response is produced, but also a cellular response, which is important for creating even more reliable protection, - continues the pediatric infectious disease specialist. - "Sputnik V" is introduced twice with an interval of three weeks.
Chinese pharmaceutical manufacturers and Johnson & Johnson also presented their vector vaccines. They need to be entered only once, but the effectiveness of the development has not yet been experimentally proven.
The third type of vaccine is protein-based vaccines. To create them, a coronavirus protein or protein fragment is used.
“They cannot cause disease, but they are able to demonstrate to the immune system proteins that are used to produce antibodies,” says Gorbunova. - Of domestic developments in this segment, EpiVacCorona is known. It contains portions of viral proteins known as peptides.
Also in the world is the development of recombinant and inactivated vaccines. So far, the effectiveness of the latter has been proven - at the level of almost 80 percent.