Rare is the person faced with the flu personally. However, even these lucky something hear and know about this very dangerous disease. How true our perceptions, it would seem, a very common infection, and so if we are knowledgeable and prepared for the new seasonal outbreak?
it’s No secret that the flu is caused by virus that enters the body through the mucous membrane cells of the respiratory system. The pathogen enters in them, and then program the victims for the creation and release of new viral copies, leaving the weakened cells of the mucosa and continues to strike new.
Thus, the virus cannot survive and reproduce unless he found for himself a host cell.
the Virus invades the cell and reproduces copies of itself, which then hit new cells.Illustration Wikimedia Commons.
How it all began?
the Viral particles of influenza was first isolated in the laboratory in the beginning of the twentieth century. The pathogen was named “plague of chickens”. In 1931 the American scientists have found this strain in pigs, and in 1933 — a man.
he was Subsequently named influenza type A. Later, scientists have discovered a type B. this couple every year, “incapacitate” millions of people across the planet.
by the Way, another kind — the influenza virus, elicits only mild forms of the illness, so for the person is harmless and usually goes unnoticed.
What, then, do all these indicate H1N1 or H5N1, about which we hear and read in the news? So experts dubbed numerous varieties variable influenza virus And which allow professionals to identify a particular pathogen. In fact, this classification describes the different subtypes of main proteins — hemagglutinin (H) and neuraminidase (N) — located on the surface of the virus.
the Schematic structure of the influenza virus. The hemagglutinin protein helps the virus to penetrate the cell, and the enzyme neuraminidase is to get out of it and continue to hit new cells.Illustration of Centers for Disease Control.
the Flu is considered one of “the Champions of infectivity”. It is spreading rapidly through airborne droplets (and this is one of the fastest ways of transmission). A growing population of large cities and a developed system of modern transport greatly facilitates virus way and contributes to massive outbreaks of illness.
Therefore, one of the most serious and real threats, the uncontrolled spread of cities and even whole countries (experts call such outbreaks and pandemics, respectively).
Pandemic of the last century
In the twentieth century, the world has experienced several pandemics. The most ambitious in the history of mankind, the infamous “Spanish flu” began in 1918. The infection raged for 18 months and killed an estimated 100 million people across the planet.
In 1958 and 1968, the world embraced “Asian” and “Hong Kong flu”. This virus has infected about 15% of the population of Hong Kong and in the United States, the disease has killed more than 30 thousand people.
Marked by a pandemic and the new century. In 2009, the world health organization announced a large-scale spread of swine flu (the infamous H1N1). Then the infection according to various estimates “caught” up to 250 million people in 140 regions of the world.
the Virus “swine flu” that caused a pandemic in 2009.Illustration of Centers for Disease Control.
However, the usual seasonal outbreaks is also not as harmless as it may seem. Who report that every year the flu kills up to 650 thousand people all over the world!
Why the flu affects zmine?
Typically, the flu makes itself at home in the cold season. First of all, this is due to the way the spread of the virus. Animal experiments confirm that airborne transmission of the pathogen occurs easier at low temperature and relative humidity.
in addition, in the winter we spend more time indoors, are more “crowding” lifestyle and have more frequent contact with a large number of people. It also facilitates virus spread.
Cold, well-developed transportation network and stay in public places facilitate the task of the virus.Photo Global Look Press.
There is another reason. Studies have shown that during cold weather the immune system is changing, and the man is easier cause inflammation, which also plays a influenza on hand.
How to protect yourself and your family from contamination?
According to leading Russian experts, the most reliable protection from seasonal outbreaks of the virus is vaccination. Its task is to prevent the uncontrolled spread of infectious diseases.
the question May arise: but we have antiviral drugs do they will not stop the epidemic?
Explain with a simple example. Picked up the flu, the first two or three days a person does not feel any symptoms of the disease, but he’s already infected. That is the moment the first signs of the flu (and to start taking the antiviral drugs) he was able to infect seven to twelve people, according to statistics. So to save from epidemics antiviral drugs are not capable of.
What a vaccine is and how it actually works?
a Vaccine is a drug that gives a person acquired immunity. Once in the body, this “trial of the disease” introduces the immune system with the pathogen. In response the body begins to produce antITELA. These substances constitute a kind of police orientation for the cells of the immune system.
In the end, when meeting with the real pathogen they quickly recognize and neutralize “criminal”, not waiting for him any explanation about who he is and what he was doing, not allowing the disease to develop. Direct and execute!
What are vaccines?
Today in the fight against influenza using two kinds of vaccines. In the production of live vaccines, as the name implies, uses a live, but weakened viruses. They are available in aerosol form and do not require injection.
non-living, or inactivated, vaccines contain either small fragments of virus (as a consequence, they are not able to infect humans), or their antigens (the same hemagglutinin and neuraminidase). These vaccines are administered intramuscularly. They are the most safe for kids and pregnant women.
How are vaccines?
The old and proven method — growing vaccines in fertilized chicken eggs. A limited number of this animal resource and time-consuming process of obtaining the drug (six months or more) make the method not the most productive.
During the long “cooking” vaccine sometimes even manages to mutate, and the ultimate strain in it already a little not in line with the planned. In addition, “egg” vaccines are contraindicated for people allergic to the proteins of the yolk.
Another method of obtaining a vaccine in cell culture, faster and more efficiently, and the desired number of cells are easy to prepare for the future in the event of a pandemic, when vaccine will require many.
to be vaccinated and getting sick
it would Seem, why, despite this extensive attention of experts to the influenza virus and the numerous developments at the curb, the vaccine sometimes fails?
Doctors often hear the phrase: “I was inoculated a couple of years ago, and now still got sick!”
All because of the rapid variability of influenza virus. The pathogen mutates constantly in response to invent a human vaccine.
For this reason, antibodies produced by the body in response to the “outdated” version of the vaccine does not correspond to the new virus. So, even a year ago, the vaccine becomes ineffective during a new outbreak. That is why vaccination is necessary every year.
do Not forget that the effectiveness of vaccination is also influenced by the age and state of health. In addition come the virus is not always 100% the same as the structure recommended in this season’s vaccine, so people sometimes get sick.
However, studies confirm that even in this case, flu, the patient will be in a much milder form and without critical complications.
it is Important to remember that the influenza vaccine will not protect against other acute respiratory viral infections that are easily confused with the flu. Therefore, when any suspicious symptoms it is best to consult a doctor who will put an accurate diagnosis.
If flu is so changeable, then who and where know what species to expect next year?
in order to keep the flu in check and to prevent the recurrence of the catastrophic events of 1918, the special Commission who annually updates the composition of influenza vaccines.
Predictions about which strains will cause the next outbreak of the flu, making it a “special Department” with a complex name for a global system of influenza surveillance and counter measures (SAGO).
This is a huge network of 144 national influenza centers in 114 countries worldwide. Its staff regularly collect and analyze samples of flu viruses collected around the world. The main task of experts is to determine the most frequently occurring strains and new varieties of the pathogen. Based on the data developed vaccine formulations for the next season.
Usually the drug is included in the three most likely causative agent: two type A and one To (trivalent vaccine). There are vaccines that contain four strains virus: two type of virus A and b (they are called tetravalent).
Every year in February, held a meeting where medical professionals get advice on flu vaccines for the new season.
And every year, doctors face a lot of questions and doubts their patients about vaccination. Some of them have already become a kind of myth. Let us examine together how they relate to reality.
the onset of the flu can be confused with other infections, but it is commonly severe and serious impact on human health.Photo Global Look
Myths and legends
the Best prevention of flu is taking vitamins. Many people believe they are safer, healthier and have no side effects.
of Course, to improve your health vitamins can. Especially if the body is deficient in valuable substances (which, however, can only be determined with appropriate tests). However, the “specialized” protection from the flu vitamins, of course, do not provide, and side effects have any of those pills.
Vaccination against the flu lowers the immune system. Because of her cold, clinging only more often.
actually the opposite. The vaccine triggers our immune system. This is the principle of its action. We emphasize again that the flu vaccine only protects against influenza virus and does not protect against other respiratory diseases.
Flu can be contracted from the vaccine itself.
It is possible. Modern preparations contain non-living flu viruses, or fragments which do not themselves cause disease.
Specify that slight discomfort, sometimes the annoying two or three days after vaccination, is perfectly normal and does not mean that a person has the flu.
the Body itself to cope with the disease.
People carry this infection in different ways. Someone who recovers within a week, someone under the same conditions gets serious complications (PNammonia, meningitis, heart damage) and even risking to die. So is it worth checking your own body for strength in a similar way?
Vaccines are dangerous, they contain mercury.
the composition of most vaccines (not just flu) is thiomersal. This preservative is based on ethyl mercury, which does not allow bacteria and fungi to multiply in vaccines. Ten years of observations have confirmed the safety of thimerosal for a human, specialists who.
by the Way, the view that in the United States and Europe “mercury” in the vaccine used, is also erroneous. For example, in the influenza season 2010-2011, the American experts used more than 90 million doses of vaccines with thimerosal.
Immunizations cause autism in children.
Scientists for many years have investigated the possible Association of autism with vaccination (“Conduct.Science” details of where the legs grow from this rather common myth). However, convincing evidence that any vaccines cause the disease, has been received.
Foreign vaccines are safe, and in Russian can contain anything.
the Production of any medication should strictly comply with certain rules, called good manufacturing practice (the GMP standard).
This “gold standard”, which is shared by Russia, European countries and the USA. Vaccine with the “random” structure does not meet strict safety standards and simply not get on the market.
Domestic and foreign vaccines are radically different from each other.
Experts point out that the antigenic composition of home and foreign vaccines are the same. Each of them always contains particles of the flu viruses expected this season. Therefore, a person can choose any vaccine.
nevertheless, some differences do exist. So, in terms of the Russian vaccine reduced the concentration of viral antigens (five micrograms in a single dose is the who recommended fifteen). At the same timethat the composition of the drug includes substances-“amplifiers” (adjuvants) that spur the immune system, so it is not inferior to other drugs.
However, this information is no clear evidence (apart from statements of the producers of the vaccine), told the correspondent of “Vesti.Science is” the family doctor Galina kuzmenkova.
in addition, in our country the most commonly used trivalent vaccines, while abroad is relatively common drugs with four types of viral antigens.
Who must be “fully armed”?
flu shots have to do everyone who is part of the so-called group of risk. It is people over 65, pregnant women and those who suffer from chronic diseases (such as diabetes, hypertension). This includes small children from six months to five years, service workers and physicians.
we Add that to prevent a flu epidemic in Russia requires that 45% of the population (and 75% of people from the risk group) were vaccinated against influenza.
How to protect yourself from influenza, if vaccination is contraindicated? And how in General to reduce the risks of getting sick?
Recall some “rules of etiquette” during outbreaks of infection. They reduce the chance of getting the flu.
don’t forget to wash your hands regularly, especially if you’ve visited public places. Though the virus and airborne, it may settle on a variety of items (the rail transport, the keyboard of ATMs and even the money), and then enter the body with dirty hands.
By the way, in the season of epidemics as little as possible touch the hands to the eyes, nose and mouth. As we have said, the virus enters the body through the mucous membranes.
Coughing and sneezing is better “elbow”, tightly closing his mouth and nose. If you have contagious, so you will reduce the risks for people who surround you.
Also, obviously, is less likely to be in crowded places and avoid BLthe low contacts a cold from the people.
When sneezing and coughing droplets of saliva releases massive amounts of the virus. Protect others — use a special mask or sneeze “in the elbow”.Photo Global Look Press.
If there is unwell, stay home and call the doctor. The time to be an introvert! The maximum limit contact with family members, wear a protective mask (it needs to be changed every two to three hours) and ventilate the room frequently.
Help antiviral drugs?
the who recommends the use of some modern antivirals if influenza developed anyway. They reduce the time of illness and relieve many complications.
However, viruses (just like bacteria), “meeting” in the Arsenal of human drugs develop resistance to them. So today no one is safe from a situation when such a drug will not work.
What’s in the future?
to save mankind from the burden of influenza, the experts are working in two key areas.
first, it is important for them as accurately as possible to predict the strain of the pathogen, which will be active in the upcoming season. This experts create different models that predict the genetic evolution of influenza virus.
second, virologists around the world are developing promising, fast in production of the vaccine. They will allow you to select the expected strains of the new season is much closer to the beginning of the outbreak. So the virus has less time to mutate and “outsmart” the newly created vaccine.
To date has tested the preparations of artificial virus-like particles that mimic the protein structure of the virus.
Vaccines on the basis of small artificial DNA (plasmids), which is inserted into the genetic material of the virus, also demonstrate mnogoebesause results in preclinical trials.
noteworthy technology and viral vectors. Such an intricate name given to harmless human viruses that scientists have adapted as a “carrier” proteins of influenza. This strategy will help to protect people against many strains of the pathogen and facilitate the composition of the vaccine.
Great expectations researchers and lay on the so-called “universal” vaccine (“Conduct.Science” are constantly monitoring such developments). These drugs are also called to deal with several strains of influenza virus, while maintaining the effectiveness in a few years and eliminates the need for annual “vaccination”.
is it Possible to eradicate influenza?
Vaccines save many lives. Thanks to them, humanity is freed from smallpox and nearly conquered polio. Remain in the past and the flu?
to answer this question, recall that the influenza A virus is widely distributed among poultry and pigs (in organisms which it mutates and eventually “learns” to infected person). Therefore, to completely get rid of it is unlikely. However, a new generation of vaccines will reduce the incidence of mismatch and the recommended strains of virus-the”hero of the season” and will allow you to not get vaccinated every year.
in Other words, people will become ill with influenza And less and easier, and outbreaks will probably be completely avoided.
There is another good news. Viruses b does not affect animals, and “take root” in the human body. This means that vaccines of new generation and mass vaccination is capable (at least theoretically) to eradicate this virus, scientists say.
Be careful about your health and do not neglect the benefits of medicine. Any prevention is better than cure. Any modern treatment of better “grandmother’s recipes”, has been disproved by science. And in order to always be updated with the latest fromevent in this important for each individual region, subscribe to our groups in social networks: VK, Facebook, Twitter, Odnoklassniki. We have in Yandex.Zen.
Text: To.Science
