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Vaccines Prevent Illness

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HealthWiki > New Where There Is No Doctor > Vaccines Prevent Illness


three adults with babies sitting in a clinic with a sign "Healthy child=healthy happy family, Vaccinations today"

Vaccinations, also called immunizations, can prevent many illnesses that might otherwise make people sick or even cause death. Vaccines work by strengthening the body’s immune system, the part of the body that fights off infection and disease so the body can regain health. If the immune system is prepared and strong, it quickly recognizes threats to health and already knows how to fight them. Vaccines do not give you the illness.

How do vaccines work? A vaccine is made of a mild or inactive germ and its presence shows the body how to stop similar germs in the future, before they make the person sick. The way the body builds this protection is by creating specific “antibodies” to successfully fight illness. These antibodies protect you and others that live around you against the germs that cause the illness.

Babies are born with some of the antibodies they need, which come directly from their mother. When mothers breastfeed, this strengthens the baby’s immune system even more. Vaccinations build the baby’s immune system as they get older. Just as good nutrition helps a child’s body grow, vaccinations help grow the immune system.

group of adults and children with umbrellas with the names of different vaccines. Above it is the words: Hepatitis B, tuberculosis,mealses, German measles, pertussis, diphteria, tetanus.
There is strength in numbers! When most people are vaccinated, their resistance to illness protects others who are too young or too sick to get the vaccination. This is called herd immunity.

Vaccinations work. Some sicknesses that killed or disabled many people in the past, such as smallpox, are now gone and the vaccine is no longer needed.

Others illnesses targeted by vaccines are becoming less common. Vaccinating all babies and children, and also adults as needed, can keep many illnesses from spreading or returning.

A vaccine protects the person who receives it, and this protects others when enough people are vaccinated. If the disease cannot find new people that are unvaccinated, it cannot spread. Over time, with more people vaccinated, there will be fewer and fewer cases.

Learn about vaccines and why we need them

Vaccines protect children from many dangerous diseases, including whooping cough, tetanus, pneumonia, measles, hepatitis B, tuberculosis, and diarrhea caused by rotavirus infection. The vaccine against HPV (a type of virus) prevents some cancers. If your children are vaccinated, they will be protected from serious illnesses.

younger woman with baby talking to an older woman.
But I have never heard of anyone having polio here.
When I was young, it was a serious problem. Now there is no polio because vaccinations are given to everyone. And they work!

Vaccinations are usually free of cost for babies and children and every country has its own schedule for when each is given. Health workers schedule visits for babies and children to make sure they are growing well, and to give the vaccinations they need to stay healthy.

Many vaccines are given more than once to help our bodies build strength against a certain disease. After a person receives the main set or series of the same vaccine, for example, 3 injections over 6 months, they may still need one or more booster vaccinations later. When the effect of the vaccine wears off, a booster is a reminder to the body about how to fight off the illness.

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What if my child is sick when vaccinations are scheduled?
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Vaccinations can be given to someone with a cold or minor illness. If a child has a serious health problem, the health worker will tell the family if a vaccination should be delayed. When others in the family and the community are vaccinated, it will help prevent sickness in those who cannot receive a vaccine.
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Are vaccines safe?
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Vaccines are safe. They do not give the illness. Some vaccines may cause some aches or a mild fever, but that will go away quickly. If you hear rumors that a vaccine is unsafe, talk to trusted health workers to get reliable information.
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Are vaccinations only for children?
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All children need vaccines but the need for vaccinations does not end after childhood. For some illnesses, older children and adults will need additional injections, called “boosters,” to stay protected. This is because over time, the effect of some vaccines wear off. Pregnant women are also vaccinated to protect the mother and the baby’s health. Older people or a person with a serious illness may benefit from a vaccination to protect against an illness such as influenza that their body may not resist well.
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The number and type of vaccinations have changed compared to my first child. Why?
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For some diseases, more than one pharmaceutical company makes a vaccine that is safe and works well. They may have different schedules. So if two countries use a different vaccine brand, or the same country changes from one to another, the schedule of injections may change too. Other changes happen when a new vaccine is created or an old one is no longer needed.
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This page was updated:23 Aug 2019