Insect virus vs. influenza virus
Flu vaccine cleared of virus
A new type of flu vaccine has been developed that does not require the use of chicken eggsOleg Vinogradov, " <url>"
A new type of flu vaccine, in the production of which neither the virus itself nor chicken eggs are used, has been approved by the US FDA: very soon this drug will appear on the American market. The vaccine is called Flublok. The main feature of this vaccine is that when it is created, an insect virus and recombinant DNA are used.
Influenza is one of the most common infectious diseases worldwide: about a billion people get sick every year. In addition, the flu often causes death. During the 1918 pandemic (the so-called Spanish woman), according to various estimates, from 20 to 50 million people died from this disease (by the way, the 2009 flu pandemic was caused by a virus of the same (A/H1N1) serotype). According to Medscape, an average of 20,000 people die from the flu virus every year.
The most effective way to combat this disease is prevention, so vaccination is crucial to prevent epidemics. The essence of vaccination is the introduction of small components of the virus into the body, which cause the immune system to produce the appropriate antibodies. Thus, when encountering an infection, a person already has reliable protection against it.
Every year, WHO, monitoring the epidemiological situation, recommends several strains of the virus for vaccination against influenza, since every year the flu is caused by a variety of virus strains (the ability to mutate quickly is one of the main properties of the influenza virus and significantly complicates the fight against it). The American Center for Disease Control and Prevention recommends that all people over 6 months of age be vaccinated annually, especially if they have a risk of developing flu complications. In Russia, mandatory vaccination is recommended only for people at risk – for example, children, as well as pregnant women, in whom the disease can cause complications for the fetus or for the course of pregnancy.
Classic flu vaccines contain small fragments of the virus envelope that can trigger an immune response in humans.
To obtain them, the influenza virus is cultured in chicken eggs. In the future, different methods of isolation and purification are used. Sometimes vaccines contain only a few surface proteins of the virus – hemagglutinin and neuraminidase, which are very important for the virus to enter the cell.
The new type of flu vaccine also contains one of these surface proteins, hemagglutinin. However, a fundamentally different mechanism was used to obtain it.
The researchers isolated a set of enzymes that read information from DNA and synthesize proteins from insect viruses, and forced them to synthesize hemagglutinin corresponding to certain strains of the influenza virus.
It is worth noting that even when using conventional vaccines, the main part of antibodies is produced against hemagglutinin.
The effectiveness of the vaccine was proven in a study on a group of 2,300 people. The volume of the control group was similar. It turned out that in about 44.6 percent of cases, the vaccine was effective against all strains of the influenza virus encountered. Among the side effects of the vaccine, headache, fatigue, pain at the injection site were sometimes encountered, although similar symptoms are characteristic of conventional flu vaccines.
"The main positive feature of the developed method of making vaccines is the ability to do it very quickly. The new technology will allow in the event of a pandemic to establish the production of vaccines very quickly, since it does not require the isolation of either the flu virus itself or chicken eggs," says Karen Midtun, director of the FDA Biological Center (Food and Drug Administration) USA.
In addition, people with allergies to chicken eggs can be vaccinated with this drug.
Portal "Eternal youth" http://vechnayamolodost.ru31.01.2013