Two polyvalent influenza vaccines
Scientists from Lancaster University have created a universal flu vaccine
marks, Geektimes
Flu epidemics cause trouble to hundreds of millions of people every year for a long period of time. According to WHO estimates, from 250 to 500 thousand people die from influenza every year. In some years, the number of victims of this dangerous disease reaches up to a million per year. Despite the fact that influenza pathogens are well studied, it is difficult to fight them. The fact is that there are hundreds of variants of the influenza virus (about 2000), which differ from each other in the antigenic spectrum. The fight against influenza viruses is complicated by the fact that their antigenic structure often changes in natural conditions.
The WHO recommended method of preventing influenza is vaccination. Unfortunately, it is not very effective. In particular, there is no data on a decrease in the spread of the virus or a decrease in the frequency of complications when using the vaccine. Also, experts have little information about the protection of adults aged 65 and older. In general, standard flu vaccines provide moderate protection against virologically confirmed influenza, but in some cases such protection is either significantly reduced or completely absent. For many years, doctors have been trying to create a universal flu vaccine that is effective against most varieties of the virus. Scientists from Lancaster University claim that they succeeded.
According to them, the vaccine is effective against 88% of known strains of the influenza virus. Moreover, only one injection is enough to protect a person. Scientists propose to carry out vaccination in winter. Doctors from Spain also participated in the project to develop this drug.
Researchers have developed two types of universal vaccine. The first one was created for the USA and is effective against 95% of influenza virus strains common in this country. The second is the global vaccine, which was discussed above. It is effective against 88% of influenza virus strains.
"Every year we vaccinate people against influenza, choosing several strains that have been active recently. Based on these strains, we are developing a vaccine, hoping that it will be effective against the pathogens of the coming epidemic. This method is safe and works well," said Derek Gatherer, one of the project participants.
He also added that in some cases this method simply does not work – this happened, for example, in 2014-2015, when the H3N2 strain spread across the planet. According to the expert, vaccines help prevent the emergence of pandemics of dangerous varieties of influenza viruses. Thus, the "Spaniard" claimed millions of lives in 1918, 1957 and 1968.
The flu still kills hundreds of thousands of people a year. Usually, a fatal outcome is characteristic of elderly people or people whose body is weakened for some reason.
To create a vaccine, specialists studied the structure of the virus, developing with the help of specialized software components of the vaccine that are effective against most known strains of the influenza virus. "Based on previously obtained information about the virus, as well as data on the human immune system, we were able to develop a vaccine that protects people much longer than conventional vaccines," said Gaterer.
The vaccine is based on the effect on special structures in the body of the virus, called "epitopes". Antibodies are attached to these structures. Vaccines of this type appeared relatively long ago, but when creating a new universal vaccine, scientists collected verified information about the vast majority of epitopes of various strains of the influenza virus. The vaccine is a mixture of dozens of known rhinoviruses.
The effectiveness of the new vaccine has been tested on mice and macaques. In all the experiments conducted with the introduction of a new vaccine, the animal body began to produce antibodies effective against the influenza virus. At the same time, scientists injected different strains of the virus into the body of mice and primates. In total, the effect of the vaccine was tested on 25 different strains in the case of mice and 50 strains in the case of macaques. In all cases, the virus was defeated by the animal's body.
If scientists from Lancaster University have really created a universal flu vaccine, it will help humanity avoid a repeat of the Spanish flu pandemic. In 1918-1919 (18 months) worldwide, about 550 million people were infected with Spanish flu (29.5% of the world's population as of the specified time period). Approximately 50-100 million people died, or 2.7–5.3% of the world's population, which makes it possible to consider this epidemic one of the most large-scale catastrophes in the history of mankind. The mortality rate among the infected was 10-20%. The epidemic began in the last months of the First World War and quickly bypassed this largest armed conflict at that time in terms of casualties. Moreover, many flu victims were not weakened – they were young and quite healthy people in the age group of 20-40 years. This flu pandemic was the most massive in the entire history of mankind in absolute numbers, both in terms of the number of infected and dead.
The results of the work of the authors of the universal vaccine were published in the journal Bioinformatics (Sheikh et al., Towards the knowledge-based design of universal influenza epitope ensemble vaccines).
Portal "Eternal youth" http://vechnayamolodost.ru 03.10.2016