Vaccinating Babies and Children: Frequently Asked Questions

No. The difference between vaccination and natural infection by a disease is the price infants have to pay to get immunity. Vaccination involves the discomfort of the injection, sometimes resulting in effects such as pain, swelling and redness at the injection site, fever, restlessness or drowsiness – but these resolve in a short while. Only in rare cases do severer side effects develop.

In contrast, the price that infants who catch these diseases pay is usually higher, involving the risk of serious illnesses. The risks may be, for example, paralysis in the case of poliovirus infection, delayed development after being infected by Haemophilus influenzae B, liver failure due to hepatitis B infection, deafness caused by meningitis after pneumococcus or mumps infection and pneumonia that may be caused by measles, whooping cough or chickenpox. These prices are too high to pay for natural immunity against the diseases.

More about possible side effects after vaccination

• To reach high efficacy: in the case of certain vaccines (mainly deactivated ones), the first dose does not provide sufficient immunity and it is necessary to administer additional doses to build up more effective immunity. For example, the vaccine for pneumococcus, which can cause meningitis, sepsis and more, is administered in 3 doses in the first year of life to reach its full efficacy.
• To increase a decreased immunity level: in other cases, such as the pentavalent vaccine that protects against diphtheria, tetanus, whooping cough, polio and Hemophilus influenzae B, the first series contains 4 doses, which are received as part of the routine vaccination for infants and children. The vaccines help build up immunity, but this gradually wanes after a few years, necessitating another dose (called a "booster dose") to restore immunity to a sufficient level. Therefore, a booster dose against diphtheria, tetanus, whooping cough and polio is administered in second grade and another booster against diphtheria, tetanus and whooping cough is administered in eighth grade.
• So that everyone ends up protected: in the case of certain vaccines (mainly live attenuated vaccines, such as the tetravalent vaccination against measles, mumps, rubella and chickenpox), it is necessary to administer more than one dose to ensure that everyone develops the optimal immune response. Not everyone is able to develop a good immune response after a single dose, but after a second dose the vast majority of vaccine recipients will develop a good, sufficient immune response that persists. The second dose gives another opportunity for those who have not developed an immune response from the first, thus helping make sure that nearly everyone is protected.
• To adapt to a mutating virus: in the case of the flu vaccine, annual vaccination is needed, because influenza viruses change from year to year. Each autumn, a new vaccine against the influenza strains that are likely to be the most common in the coming flu season is developed.

No. The routine vaccination program currently in place in Israel includes vaccination for infants and children against 14 diseases, administered at family health centers and later at schools. There is no need to fear that they will not be able to cope with multiple vaccines. Remember that the immune systems of infants and toddlers cope with many more challenges besides vaccination. In fact, infants are capable of reacting to millions of viruses and bacteria, because their bodies have millions of mature cells that are ready for the immune system’s action.

No. The immune systems of infants and children are capable of coping with the number of vaccines recommended in the routine vaccination program. Splitting the vaccination does not reduce the pain of injections, and if one vaccine is separated from a combined vaccination, it will require more injections. In addition, splitting postpones the time of vaccination, leaving your child exposed to disease that can be prevented.

Vaccines, even if they contain live attenuated viruses, do not weaken the immune system. In contrast, natural infection with certain viruses can weaken it, for example:

• Catching chickenpox increases the risk of catching bacterial infections.
• Children who have had measles are prone to bacterial infections of the blood stream (sepsis).

“Herd immunity” forms when the majority of the population is vaccinated, in which case the risk of disease transmission between individuals decreases, including those who are unvaccinated. Usually, to reach this state, there must be a high proportion of vaccinated people in the population. The percentage of vaccinated people in the population required to achieve herd immunity varies from between diseases. For example, to achieve herd immunity against measles, which is highly contagious, a 95% vaccination rate is required.

However, herd immunity is partial. It can protect children only if they are in a society in which there is a high percentage of vaccinated individuals. If an unvaccinated child is in direct contact with a patient who has one of the diseases against which the vaccines protect, they can contract the diseases, even if those closest to them are vaccinated.

No. Many studies have assessed whether vaccination increases the risk of sudden infant death syndrome, and no evidence of this has been found. In fact, vaccinated infants are better protected against a range of infections, and are therefore better protected against sudden infant death syndrome, which is sometimes caused by an unidentified infection.

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No. A study that was conducted at the US Center for Disease Control (CDC) found no difference in the frequency of diabetes in vaccinated and unvaccinated children. Another study showed that the frequency of diabetes was identical among children vaccinated at an early age and those vaccinated later in life. There is no scientific evidence supporting the deferral of vaccination to prevent diabetes.

No, there is no connection between vaccines and autism! International experts and comprehensive studies have come to a conclusion that leaves no room for doubt that vaccines in general and the mumps, measles and rubella (MMR) vaccine in particular, do not cause autism.

More about vaccination safety