Vaccines what is it
Vaccines and immunization: What is vaccination?
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- Vaccines and immunization: What is vaccination?
30 August 2021 | Q&A
Updated on 30 August 2021.
What is vaccination?
Vaccination is a simple, safe, and effective way of protecting you against harmful diseases, before you come into contact with them. It uses your body’s natural defenses to build resistance to specific infections and makes your immune system stronger.
Vaccines train your immune system to create antibodies, just as it does when it’s exposed to a disease. However, because vaccines contain only killed or weakened forms of germs like viruses or bacteria, they do not cause the disease or put you at risk of its complications.
Most vaccines are given by an injection, but some are given orally (by mouth) or sprayed into the nose.
How does a vaccine work?
Vaccines reduce risks of getting a disease by working with your body’s natural defenses to build protection. When you get a vaccine, your immune system responds. It:
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Recognizes the invading germ, such as the virus or bacteria.
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Produces antibodies. Antibodies are proteins produced naturally by the immune system to fight disease.
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Remembers the disease and how to fight it. If you are then exposed to the germ in the future, your immune system can quickly destroy it before you become unwell.
The vaccine is therefore a safe and clever way to produce an immune response in the body, without causing illness.
Our immune systems are designed to remember. Once exposed to one or more doses of a vaccine, we typically remain protected against a disease for years, decades or even a lifetime. This is what makes vaccines so effective. Rather than treating a disease after it occurs, vaccines prevent us in the first instance from getting sick.
When should I get vaccinated (or vaccinate my child)?
Vaccines protect us throughout life and at different ages, from birth to childhood, as teenagers and into old age. In most countries you will be given a vaccination card that tells you what vaccines you or your child have had and when the next vaccines or booster doses are due.
It is important to make sure that all these vaccines are up to date.
If we delay vaccination, we are at risk of getting seriously sick. If we wait until we think we may be exposed to a serious illness – like during a disease outbreak – there may not be enough time for the vaccine to work and to receive all the recommended doses.
If you have missed any recommended vaccinations for you or your child, talk to your healthcare worker about catching up.
Why should I get vaccinated?
Without vaccines, we are at risk of serious illness and disability from diseases like measles, meningitis, pneumonia, tetanus and polio. Many of these diseases can be life-threatening. WHO estimates that childhood vaccines alone save over 4 million lives every year.
Although some diseases may have become uncommon, the germs that cause them continue to circulate in some or all parts of the world.
In today’s world, infectious diseases can easily cross borders, and infect anyone who is not protected
Two key reasons to get vaccinated are to protect ourselves and to protect those around us. Because not everyone can be vaccinated – including very young babies, those who are seriously ill or have certain allergies – they depend on others being vaccinated to ensure they are also safe from vaccine-preventable diseases.
What diseases do vaccines prevent?
Vaccines protect against many different diseases, including:
- Cervical cancer
- Cholera
- COVID-19
- Diphtheria
- Ebola virus disease
- Hepatitis B
- Influenza
- Japanese encephalitis
- Measles
- Meningitis
- Mumps
- Pertussis
- Pneumonia
- Polio
- Rabies
- Rotavirus
- Rubella
- Tetanus
- Typhoid
- Varicella
- Yellow fever
Some other vaccines are currently under development or being piloted, including those that protect against Zika virus or malaria, but are not yet widely available globally.
Not all of these vaccinations may be needed in your country. Some may only be given prior to travel, in areas of risk, or to people in high-risk occupations. Talk to your healthcare worker to find out what vaccinations are needed for you and your family.
Who can get vaccinated?
Nearly everyone can get vaccinated. However, because of some medical conditions, some people should not get certain vaccines, or should wait before getting them. These conditions can include:
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Chronic illnesses or treatments (like chemotherapy) that affect the immune system;
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Severe and life-threatening allergies to vaccine ingredients, which are very rare;
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If you have severe illness and a high fever on the day of vaccination.
These factors often vary for each vaccine. If you’re not sure if you or your child should get a particular vaccine, talk to your health worker. They can help you make an informed choice about vaccination for you or your child.
What is in a vaccine?
All the ingredients of a vaccine play an important role in ensuring a vaccine is safe and effective. Some of these include:
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The antigen. This is a killed or weakened form of a virus or bacteria, which trains our bodies to recognize and fight the disease if we encounter it in the future.
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Adjuvants, which help to boost our immune response. This means they help vaccines to work better.
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Preservatives, which ensure a vaccine stays effective.
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Stabilisers, which protect the vaccine during storage and transportation.
Vaccine ingredients can look unfamiliar when they are listed on a label. However, many of the components used in vaccines occur naturally in the body, in the environment, and in the foods we eat. All of the ingredients in vaccines – as well as the vaccines themselves - are thoroughly tested and monitored to ensure they are safe.
Are vaccines safe?
Vaccination is safe and side effects from a vaccine are usually minor and temporary, such as a sore arm or mild fever.
More serious side effects are possible, but extremely rare.
Any licensed vaccine is rigorously tested across multiple phases of trials before it is approved for use, and regularly reassessed once it is introduced. Scientists are also constantly monitoring information from several sources for any sign that a vaccine may cause health risks.
Remember, you are far more likely to be seriously injured by a vaccine-preventable disease than by a vaccine. For example, tetanus can cause extreme pain, muscle spasms (lockjaw) and blood clots, measles can cause encephalitis (an infection of the brain) and blindness. Many vaccine-preventable diseases can even result in death. The benefits of vaccination greatly outweigh the risks, and many more illnesses and deaths would occur without vaccines.
More information about vaccine safety and development is available here.
Are there side effects from vaccines?
Like any medicine, vaccines can cause mild side effects, such as a low-grade fever, or pain or redness at the injection site.
Mild reactions go away within a few days on their own.
Severe or long-lasting side effects are extremely rare. Vaccines are continually monitored for safety, to detect rare adverse events.
Can a child be given more than one vaccine at a time?
Scientific evidence shows that giving several vaccines at the same time has no negative effect. Children are exposed to several hundred foreign substances that trigger an immune response every day. The simple act of eating food introduces new germs into the body, and numerous bacteria live in the mouth and nose.
When a combined vaccination is possible (e.g. for diphtheria, pertussis and tetanus), this means fewer injections and reduces discomfort for the child. It also means that your child is getting the right vaccine at the right time, to avoid the risk of contracting a potentially deadly disease.
Is there a link between vaccines and autism?
There is no evidence of any link between vaccines and autism or autistic disorders.
This has been demonstrated in many studies, conducted across very large populations.
The 1998 study which raised concerns about a possible link between measles-mumps-rubella (MMR) vaccine and autism was later found to be seriously flawed and fraudulent. The paper was subsequently retracted by the journal that published it, and the doctor that published it lost his medical license. Unfortunately, its publication created fear that led to dropping immunization rates in some countries, and subsequent outbreaks of these diseases.
We must all ensure we are taking steps to share only credible, scientific information on vaccines, and the diseases they prevent.
Should my daughter get vaccinated against human papillomavirus (HPV)?
Virtually all cervical cancer cases start with a sexually transmitted HPV infection. If given before exposure to the virus, vaccination offers the best protection against this disease. Following vaccination, reductions of up to 90% in HPV infections in teenage girls and young women have been demonstrated by studies conducted in Australia, Belgium, Germany, New Zealand, Sweden, the United Kingdom and the United States of America.
In studies, the HPV vaccine has been shown to be safe and effective. WHO recommends that all girls aged 9–14 years receive 2 doses of the vaccine, alongside cervical cancer screening later in life.
I still have questions about vaccination. What should I do?
If you have questions about vaccines be sure to talk to your healthcare worker. He or she can provide you with science-based advice about vaccination for you and your family, including the recommended vaccination schedule in your country.
When looking online for information about vaccines, be sure to consult only trustworthy sources. To help you find them, WHO has reviewed and ‘certified’ many websites across the world that provide only information based on reliable scientific evidence and independent reviews by leading technical experts. These websites are all members of the Vaccine Safety Net.
What's in Vaccines? Ingredients and Vaccine Safety
Español (Spanish)
Today’s vaccines use only the ingredients they need to be as safe and effective as possible.
- Every ingredient serves a purpose
- Ingredients found in some vaccines
- Ingredients in specific vaccines
Every vaccine ingredient serves a purpose
To provide immunity
We become immune to (or protected from) a disease when our bodies create specific antibodies to fight that disease. Vaccines contain ingredients that help your body build this immunity.
To keep the vaccine safe and long-lasting
Vaccines need to be safe and effective. Certain ingredients help keep vaccines safe from contamination and toxins. Others, like stabilizers, help vaccines stay effective for a long time.
To make the vaccine more effective
All vaccine ingredients help to make a vaccine as effective as possible, while being safe. Ingredients like aluminum salt help boost the body’s response to the vaccine.
Ingredients found in some vaccines
Purpose: To keep the vaccine effective after manufacturing
Most commonly found in: Jell-O®, naturally in the body
Examples: Sugars, gelatin
Purpose: To help boost the body’s response to the vaccine
Most commonly found in: Drinking water, infant formula, and some health products such as antacids, buffered aspirin, and antiperspirants
Examples: Aluminum salts
Purpose: To kill viruses or inactivate toxins during the manufacturing process
Most commonly found in: Naturally in the human body, fruit, household furnishings (carpets, upholstering)
Example: Formaldehyde†
Purpose: To grow enough of the virus or bacteria to make the vaccine
Most commonly found in: Eggs, and foods that contain eggs
Examples: Egg protein^
Purpose: To prevent contamination by bacteria during the vaccine manufacturing process
Most commonly found in: Common antibiotics.
Antibiotics that people are most likely to be allergic to—like penicillin—aren’t used in vaccines.
Examples: Neomycin, Kanamycin, Streptomycin
Purpose: To prevent contamination
Most commonly found in: Some kinds of fish
Example: Thimerosal (only in multi-dose vials of flu vaccine)*
Most vaccines don’t contain any mercury
Most vaccines do not have any mercury in them. However, multi-dose flu vaccines and one type of Td vaccine contain a small amount of thimerosal. Thimerosal contains a form of mercury (ethylmercury) that does not cause mercury poisoning and is safe for use in vaccines. Flu and Td vaccines are also available in thimerosal-free versions.
Different types of vaccines work in different ways
Vaccines can help protect against certain diseases by imitating an infection. This helps teach the immune system how to build immunity to fight off a future infection. Different vaccines provide immunity in different ways.
Because influenza and yellow fever vaccines are both made in eggs, egg proteins are present in the final products. For people with egg allergies, there are now two new flu vaccines available. People with severe egg allergies should be vaccinated in a medical setting and be supervised by a health care professional who can recognize and manage severe allergic conditions.
* Thimerosal contains a different form of mercury (ethylmercury) than the kind that causes mercury poisoning (methylmercury). Ethylmercury is safe to use in vaccines because it’s processed differently in the body and is less likely to build up in the body—and because it’s used in tiny amounts. Even so, most vaccines do not have any thimerosal in them. Learn more about thimerosal, mercury, and vaccine safety.
Vaccine information for you and your family
- Vaccines for Your Children
- Pregnancy and Vaccination
- Adult Vaccination
- Basic and Common Questions
Vaccination: what is it - what is vaccination for
Vaccination - is the protection of mankind from a number of infectious diseases.
Many people think that vaccinations appeared relatively recently - in the last century. In fact, the history of vaccinations is rooted in the distant past. The first written mention of vaccination indicates the use of vaccination against smallpox already about 3 thousand years ago! 1 Today vaccination is a way to protect against serious infectious diseases, which can be controlled by vaccination. 2
Why is vaccination called vaccination?
How does immunity work?
How does the vaccine work?
Achievements in vaccination
Why is the vaccination schedule important?
Why is vaccination called vaccination?
Do you know where the word "vaccine" and "vaccination" come from?
In the late 18th century, English physician Edward Jenner developed a safe way to protect people against smallpox by inoculating them with cowpox.
From the Latin word "vacca" - "cow" later came the name "vaccine", and the method of protection became known as vaccination. The spread of smallpox vaccination was a turning point in saving people from a previously invincible disease.
A century later, the French scientist Louis Pasteur made a breakthrough in medicine. He showed that infectious diseases are caused by microbes. In 1880, Louis Pasteur developed a method of protection against "contagious diseases" by introducing live attenuated pathogens. 1.3
Vaccination can protect us from infectious diseases, many of which lead to disability and death even today with modern treatment. 2 Vaccinations activate the body's natural defenses against pathogens (infections) and teach our immune system how to defend itself. 1.4
How does immunity work?
Our immune system is our guardian and protector against infections.
1,2,4,5 When faced with an infection, a person may get sick. At the same time, our immune system recognizes viruses or bacteria as foreign agents and begins to produce special proteins - antibodies to destroy them. 1.4 Interestingly, the immune system creates specific antibodies against each virus and bacteria.
At the same time, the body creates memory cells and, as it were, remembers each infectious agent. The next time you come into contact with a virus or bacterium, your immune system will react much faster than the first encounter. This allows us to protect us from the disease or from its severe course. 2.4
Learn more about how the immune system works in article How does the immune system work? .
It is important to note that it is possible to protect the body from a dangerous infection not only by being ill. Vaccination is capable of conferring protective immunity without exposing the individual to the risk of disease.
Vaccines are medicines specially designed to activate the natural protective mechanisms of immunity without causing an infectious disease. 1.2
How does a vaccine work?
The main purpose of vaccination is the formation of immunity (resistance) to the disease.
This becomes possible when grafting (vaccination) is the introduction into the human body of a whole weakened or killed pathogen of the infection against which the vaccine is being given, or a fragment of this pathogen (antigen). 2,4,5
Does the immune system react naturally when a vaccine is given?
The same way she would react when she first encounters an infectious agent. The immune system will also attack the weakened or non-living form of bacteria or viruses from the vaccine, produce antibodies to fight them, and form memory cells. 2,4,5
To form a stable immune response against some infections, sometimes a single injection of the vaccine is enough, against others - several doses with an interval of several weeks, months and even years.
The memory of the causative agent of the disease accumulates, and if a vaccinated person, even years later, encounters a disease, an already trained immune system will be ready to meet the “enemy”. 2,4,5
Achievements in vaccine prevention
Preventing the spread of infections through vaccines is without a doubt one of the greatest achievements of mankind in the field of medicine. In 1999, a list of the 10 most significant global health achievements of the 20th century was published. Vaccination is at the top of this list. 5
Preventing the spread of infections through vaccines is without a doubt one of mankind's greatest achievements in the field of medicine. At 19In 1999, a list of the 10 most significant global health achievements of the 20th century was published. Vaccination is at the top of this list. 5
- With the introduction of vaccination, more than 10 severe infections have been eradicated or reduced to isolated cases.
- Globally Smallpox eradicated Most regions Polio eradicated Americas declared world's first free region in 2016 for measles. 5
Vaccination to protect against infections is used throughout the world. Every country has a National Immunization Schedule. 5
Why is the vaccination schedule important?
Vaccination Schedule defines schemes and rules for administering vaccinations , protecting children and adults against various infectious diseases. 5.6
In Russia, the current vaccination calendar was approved by Order of the Russian Ministry of Health of December 6, 2021 N 1122n "On approval of the National calendar of preventive vaccinations, the calendar of preventive vaccinations for epidemic indications and the procedure for conducting preventive vaccinations."
The national calendar of preventive vaccinations in Russia regulates vaccination, that is, protection against:
- 12 infectious diseases in a planned manner and against
- 24 (!) infections according to epidemic indications.
5.6
This is the largest list, which has no analogues in the world. It was developed taking into account the widest climatic and geographical features of our country, various professional groups of the population and other factors. 5.6
Read more about the National Immunization Calendar here.
- Immunology according to Yarilin: textbook / ed. S. A. Nedospasova, D. V. Kurpasha. - 2nd ed., Rev. and additional - Moscow: GEOTAR-Media, 2021. - 808s.
- WHO. Vaccines and immunization: What is vaccination? https://www.who.int/ru/news-room/q-a-detail/vaccines-and-immunization-what-is-vaccination (Accessed 29.04.2024)
- Vaccination specialists. The first experiments of vaccination. https://yaprivit.ru/vaccination-history/pervye-opyty-vaccinacii/ (accessed 29.04.2022)
- WHO. How do vaccines work?
- Vaccines and immunoprophylaxis in the modern world: a guide for doctors / ed. L.S. Namazova-Baranova, N.
I. Briko, I.V. Feldblum. - Moscow: Pediatr, 2021. - 612 p. - Order of the Ministry of Health of Russia No. 1122n dated 06.12.2021 "On approval of the national calendar of preventive vaccinations, the calendar of preventive vaccinations for epidemic indications and the procedure for conducting preventive vaccinations for epidemic indications" (version 2021)
MAT-RU-2201514_v1.0_02_2022
What are vaccinations and what are they for - Where do myths about vaccinations come from? Like any rumors and misconceptions, vaccination myths arise due to a lack of information, and even more so reliable information, which gives rise to various kinds of speculation, unfounded fears. - Health Articles - Patients
Where Do Vaccine Myths Come From? Like any rumors and misconceptions, vaccination myths arise due to a lack of information, and even more so reliable information, which gives rise to various kinds of speculation, unfounded fears.
Today, the question of why preventive vaccinations are needed is of great interest.
Everyone has the right to make decisions about their health and the health of their child. To make a decision, it is necessary to understand what vaccinations are, what are their advantages and disadvantages.
Vaccination is the introduction into the body of a substance that is recognized by the immune system as the causative agent of an infectious disease, as a result of which an immune response develops, which in turn leads to the production of antibodies that neutralize the pathogen upon repeated penetration.
Vaccines differ in composition:
- live vaccines containing pathogens
- inactivated vaccines contain "killed" pathogens
- recombinant vaccines - preparations that include only parts of microbial cells waste products) pathogens.
- None of the above can cause disease!
The strength of the immune response depends primarily on the characteristics of the organism.
In most vaccinated individuals, contact with the pathogen does not develop the disease. In rare cases, a vaccinated person can get sick, but the disease is milder, and the risk of complications is significantly reduced.
Just a recent example. This winter, there was an influenza epidemic in the territory of the Rezhevsky District, and in other areas, as well as in other areas. In total, 41 cases were registered in our district, of which 11 people in serious condition were rehospitalized in Yekaterinburg, and as it turned out, they were not vaccinated. You can also emphasize the effectiveness of vaccination against tick-borne encephalitis. In 2010, not a single case of tick-borne encephalitis was registered. And only 10 cases - Lyme disease (tick-borne borreliosis).
Thanks to vaccinations, diseases such as poliomyelitis and smallpox, as well as the so-called controlled childhood infections, which in the recent past caused the death and severe disability of millions of people, have been eradicated in our country.
Vaccines can prevent liver cancer (which develops as a result of viral hepatitis), cervical cancer (of which the human papillomavirus is a common cause). As for cervical cancer, more than 12 thousand women fall ill with this disease every year in the Russian Federation. In recent years, there has been a clear trend towards an increase in the incidence of women under the age of 35.
The human papillomavirus (HPV) vaccine can protect a girl from being infected with the HPV strains that most cause genital warts and cervical cancer. Girls, girls should be vaccinated at the age of 11-12 years. Girls can also be vaccinated against papillomavirus starting at age 9. Vaccination is also recommended for girls aged 13 to 26 who have not been vaccinated. It is best if the girl is vaccinated against papillomavirus before the onset of sexual activity.
For effective vaccination, certain vaccination rules must be observed:
- observe the intervals between vaccinations
- if the vaccine is purchased in a pharmacy, it is necessary to follow the rules for storing and transporting vaccines
- the vaccine must be purchased directly on the day of vaccination .
