How your baby's immune system develops | Pregnancy Birth and Baby beginning of content
Babies' immune systems are not as strong as those of adults. Breastfeeding and vaccinating your baby will help protect them from a serious illness.
What is the immune system?
Your immune system is a network of cells and proteins that are found throughout your body. The immune system fights germs that cause infection.
Germs such as bacteria and viruses are sometimes described as ‘foreign’. This is because they don’t belong in our bodies. Germs can cause your baby to become sick.
If bacteria, a virus or something foreign gets into your body, the immune system starts to act quickly. White blood cells notice that something foreign has entered your body. The white blood cells make special proteins called ‘antibodies’, and also switch on other parts of the immune system. This is called the ‘immune response’ and it fights the infection.
After antibodies have been made, the immune system can 'remember' the germ or virus. This helps the body to fight the germ more easily next time. This memory is called ‘immunity’.
The immune system in babies
A baby’s immune system is not fully developed when they are born. It gets stronger as the baby gets older. The immune system works throughout our lives fighting germs that can cause disease.
A mother’s antibodies are shared with their baby through the placenta during the third trimester (last 3 months) of pregnancy. The mother’s antibodies help protect the baby from illnesses when the baby is born. The type of antibodies passed from mother to baby depends on the mother’s own level of immunity.
Good bacteria in our gut help our immune system to work well. During birth, these good bacteria are in the vagina and are passed on to the baby. This helps good bacteria to start living in the baby’s gut.
After birth, more antibodies are passed to your baby from the colostrum and in breast milk.
Premature babies do not receive as many antibodies from their mothers as full-term babies. Their immune systems are not very strong. Premature babies have a greater chance of getting sick from germs like bacteria and viruses.
How to boost your baby’s immune system
The immunity that your baby receives from their mother at birth does not last long. It will gradually go away after a few weeks or months.
Babies make their own antibodies. Each time they get infected with a virus or other germ, their immune system starts to work. They make new antibodies that will protect them now and in the future.
But immunity in a baby is not as strong as in adults. And it takes time to fully develop. In the meantime, there are some important things you can do to protect your baby.
Breast milk contains many good things to help build your baby’s immune system. These include proteins, fats, and sugars, as well as antibodies and probiotics. When a mother comes into contact with germs, she makes antibodies to help her fight the infection. These are passed to the baby in breast milk. Because mothers and babies usually come into contact with the same germs, the mother’s breast milk can protect the baby.
Breastfed babies have fewer infections and get better more quickly than formula-fed babies. However, for mothers who are unable to breastfeed or who choose not to, infant formula is a healthy option.
Breastfeeding cannot fully protect your baby from life-threatening infections like polio, diphtheria or measles. These diseases are very serious and can make your baby very sick. Fortunately, we now have vaccines that work with the immune system to protect your baby.
Vaccinating your children is the safest and most effective way to protect them against serious disease.
Vaccination causes an immune response in the same way that a virus or bacteria would. But it makes an immune response happen without the child actually getting sick. The vaccine makes your child ‘immune’. If your child catches the real disease in future, their immune system will remember the germ. The immune response will swing into action and fight off the disease, or prevent serious complications.
You can be vaccinated for whooping cough in your third trimester or pregnancy. This helps pass on your immunity against whooping cough to your baby.
You can also be vaccinated against influenza (the ‘flu’) when pregnant. This is recommended at any stage of pregnancy, but should happen before the ‘flu’ season starts. Your antibodies to the flu vaccine are also passed on to your baby.
Your baby’s first vaccines are given at birth, then at 6 weeks, 4 months and 6 months of age. Other vaccines and boosters are given over the first few years of life.
Diet and supplements
Taking antibiotics kills some of the good gut bacteria that are important for immunity. Some people think that probiotics can boost immunity after they have had antibiotics. Probiotics are safe for women to use in late pregnancy and after the baby is born. However, it is not clear if probiotics are useful for children or adults. Talk to your doctor before giving probiotics to your baby.
In most cases, breast milk and formula provide all the vitamins and minerals your baby needs. Giving extra vitamins is not recommended for babies.
Once your baby starts on solids, a range of fresh foods should be enough to keep their immune system healthy. This can include different types of pureed vegetables and fruits. Try to keep breastfeeding at the same time as starting solid food.
Speak to a maternal child health nurse
Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available 7am to midnight (AET), 7 days a week.
Australian Government Department of Health (Influenza vaccination in pregnancy)
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Last reviewed: May 2022
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Infant Immune Systems Are Stronger Than You Think
New study may help explain why infants are less affected by COVID than adults
December 10, 2021
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As any parent knows, infants are prone to getting respiratory infections.
But a new study shows that the infant immune system is stronger than most people think and beats adults at fighting off new pathogens.
The infant immune system has a reputation for being weak and underdeveloped when compared to the adult immune system, but the comparison isn’t quite fair, says Donna Farber, PhD, professor of microbiology & immunology and the George H. Humphreys II Professor of Surgical Sciences at Columbia University Vagelos College of Physicians and Surgeons.
Watching T cells react to flu antigens helped the researchers identify why naive T cells from infant mice (shown above) responded faster and more robustly to the pathogen than the same cells from adult mice. The colors in the images represent different molecules involved in T cell activation. Images from the Farber laboratory/Columbia University Irving Medical Center.
Babies do get a lot of respiratory illnesses from viruses, like influenza and respiratory syncytial virus, compared to adults. But unlike adults, babies are seeing these viruses for the first time. “Adults don’t get sick as often because we’ve recorded memories of these viruse, and the memories protect us,” Farber says, “whereas everything the baby encounters is new to them.”
In the new study, Farber and colleagues leveled the playing field and only tested the immune system’s ability to respond to a new pathogen, essentially eliminating any contribution from immunological memories.
For the head-to-head comparison, the researchers collected naïve T cells—immune cells that have never encountered a pathogen—from both infant and adult mice. The cells were placed into an adult mouse infected with a virus.
In the competition to eradicate the virus, the infant T cells won handily: Naïve T cells from infant mice detect lower levels of the virus than adult cells and the infant cells proliferated faster and traveled in greater numbers to the site of infection, rapidly building a strong defense against the virus. A laboratory comparison found similar enhancements among human infant compared to adult T cells.
“We were looking at naïve T cells that have never been activated, so it was a surprise that they behaved differently based on age,” Farber says. “What this is saying is that the infant’s immune system is robust, it's efficient, and it can get rid of pathogens in early life. In some ways, it may be even better than the adult immune system, since it’s designed to respond to a multitude of new pathogens. ”
That appears to be playing out in the case of COVID. “SARS-CoV-2 is new to absolutely everybody, so we’re now seeing a natural, side-by-side comparison of the adult and infant immune system,” Farber says. “And the kids are doing much better. Adults faced with a novel pathogen are slower to react. That gives the virus a chance to replicate more, and that’s when you get sick.”
The findings also help explain why vaccines are particularly effective in childhood, when T cells are very robust. “That is the time to get vaccines and you shouldn't worry about getting multiple vaccines in that window,” Farber says. “Any child living in the world, particularly before we started wearing masks, is exposed to a huge number of new antigens every day. They’re already handling multiple exposures.”
The study could lead to better vaccine designs for children.
“Most vaccine formulations and doses are the same for all ages, but understanding the distinct immune responses in childhood suggests we can use lower doses for children and could help us design vaccines that are more effective for this age group,” Farber says.
The paper, titled "Infant T cells are developmentally adapted for robust lung immune responses through enhanced T cell receptor signaling," was published Dec. 10 in Science Immunology.
Donna Farber also is chief of the Division of Surgical Sciences in the Department of Surgery, Columbia University Vagelos College of Physicians and Surgeons, and principal investigator at the Columbia Center for Translational Immunology.
All authors (all from Columbia University unless noted): Puspa Thapa, Rebecca S. Guyer, Alexander Y. Yang, Christopher A. Parks, Todd M. Brusko (University of Florida), Maigan Brusko (University of Florida), Thomas J. Connors, and Donna L. Farber.
This work was supported by the U.S. National Institutes of Health (NIH grants AI100119, AI106697, K23 AI141686, and AI42288) and the Helmsley Charitable Trust. Studies were performed in the Columbia Center for Translational Immunology’s Flow Cytometry Core, supported by NIH grants S10RR027050 and S10OD020056, and the Columbia Stem Cell Initiative’s Flow Core, supported in part by NIH grant S10OD026845.
The authors declared no competing interests.
Immunity of the child. How to increase the child's immunity? › Clinic "Forpost"
Before you think about how to increase the immunity of a child, make sure that this is not a congenital disorder!
In children, before trying to increase immunity, it is necessary to determine whether this disorder is congenital. It is in childhood that a disease such as congenital immunodeficiency manifests itself. Parents often noticing some problems with the baby’s health (frequent colds in a child, it takes a long time to recover, weak, etc.), assuming that weak immunity is the culprit of all this, they try by all means to increase it. And if you stimulate the immune system against the background of some kind of congenital pathology, then this can lead to unforeseen consequences. And not only will it not strengthen the immune system, but it will also harm. Stimulating and spurring a child's weakened and depleted immunity will only lead to even greater exhaustion and failure in his work. nine0003
Indications for visiting an immunologist:
the child has ARVI more than 6 times a year;
complications occur after colds;
the baby suffers from allergies;
the child has a herpes rash on the lips;
more than once the child had purulent otitis media or pneumonia, etc.
If persistent disorders occur for more than half a year or a year, it is important for the child to have an immunogram. It is advisable to conduct an immunogram for a child after 3 years, then it already better reflects the state of the child's immunity and becomes informative. nine0003
How to raise immunity in a child with acquired immunodeficiency
So, the first thing to do in childhood is to determine the congenital or acquired functional insufficiency of the immune system in a child. In the case of a non-congenital, but an acquired disorder, more emphasis should be placed on increasing the non-specific factors that strengthen the child's immunity. There is no need to give some strong immunostimulants, immune preparations to children, as adults. Children should be approached more subtly, because children have more physiological immunodeficiency. So nature itself came up with the idea that the child's body should get acquainted with all infections and it is easier to endure them in childhood. Everyone knows that it is better to get chickenpox just in childhood. After all, children are much easier to tolerate high temperatures than adults. nine0003
Recommendations: how to strengthen the immunity of a child
After examination and laboratory tests, if the immune system is stimulated, then more by physiological methods. This applies to the daily routine, child nutrition, hardening, drugs that provide additional protein for the immune system.
In extreme cases, with more persistent disorders, immunomodulators or immune preparations with a substitution purpose are appropriate (viferon is a ready-made interferon for a certain period of time to support the child’s immune system, nucleinate is a protein donor, etc. ) There are many immunomodulators , which increase the activity of the immune system and strengthen the body's ability to resist infections. nine0003
However, the main thing that parents should understand is that immunotherapy should not become a platform for experiments on their own child. You can take such drugs only as prescribed by a doctor and after the fact of immunodeficiency or any disorder in the immune system is established on the basis of an examination of the baby and a study of the results of his laboratory tests.
Natural stimulants of the child's immunity
These are hunger, cold and physical activity. Extremism is unacceptable in none of the three indicated directions - there is no need to deliberately starve a child, overload it with physical exercises or force it to freeze. But something else is more important: the opposite actions (excessive food and heat, restriction of motor activity) very quickly lead to suppression of the immune system (frequent infectious diseases) or to perverted immune reactions, that is, it seems to react, but not as it should (allergic or infectious-allergic diseases). nine0003
The correct daily routine will help increase the child's immunity
It is important that the child is not exhausted and not overtired.
Every child has a significantly accelerated metabolism compared to adults. Therefore, on the one hand, the child is depleted faster, and on the other hand, it recovers faster than an adult. The excretory organs work better, everything in the body of children works faster, burns out faster, but new things are born faster.
Sufficient sleep helps to strengthen the child's immunity
For strong immunity, a child needs to sleep twice a day: at night and during the day, while sleeping longer at night than adults. During sleep, children grow better because the metabolism during sleep in children remains faster than in adults. Proper rest affects the cells of the immune system and helps to increase the immunity of the child.
Rational and proper nutrition will strengthen the child's immunity
The child's nutrition should be more frequent, because the enzymatic system is still immature, it cannot digest and assimilate a lot of food at one meal. Therefore, the child should not be overfed, he must be given food in small portions, but more often than an adult. And food should be more varied, contain more vitamins, because of the same accelerated metabolism. Therefore, to strengthen the child's immunity, it is necessary that the body has enough vitamins, trace elements, proteins and other useful and necessary substances. Remember that the child is also still growing and he needs to add in body weight. nine0003
Good functioning of the digestive system is directly related to a strong and healthy immune system. After all, about 60-70% of immune cells are in the gastrointestinal tract! It becomes clear that proper nutrition in the formation of powerful immunity in a child plays an important role.
Hardening is an excellent way to increase the child's immunity
In children, as in adults, there are a lot of receptors on the ears, palms and soles, which are connected with the whole body. If you irritate and create some extreme conditions for these receptors, they will give a message or impulse to combat readiness in all organs and systems, including the immune system. nine0003
What is the essence of hardening in strengthening the immunity of a child
Most people are sure that hardening is accustoming to the cold. For example, walking in the snow in shorts, etc.
In fact, the essence of hardening is to train the mucous membranes to quickly respond to a sharp change in temperature. After such training, the mucous membranes become a serious obstacle to a viral infection.
How to harden a child in order to strengthen the immune system?
Simple workout - alternating "treatment" with cold and hot water of the forearms - from the hand to the elbow, from the feet to the knee. Let's define the water temperature: cold - +20 °C, hot - +35 °C. Both of them cannot cause negative feelings in the child. And contrast plays a role in hardening. In this case, the same “tolerable” difference of 15 ° C. Douching should be done daily - 5-7 minutes a day. It doesn't matter if it's morning or evening. But for a very long time - from autumn to the end of spring. nine0003
During this alert, stress hormones are produced. These hormones tone the blood vessels and the entire body to combat readiness. Constantly the immune system and the body cannot be in this state and produce stress hormones. But there are people who have a lack of these hormones, and it is also useful for people who sleep for a long time, move little and are emotionally sluggish.
The psychological state of the child is an important factor in healthy immunity
The psychological factor is very important, the mood greatly affects the state of the child's immunity. Again, through stress hormones: positive emotion is also stress, negative emotion is also stress. When a child is not noticed, not given food for development, this negatively affects his immune system. It is important to train the child's resistance to stress, which will later affect the stability of the immune system. This is also a kind of immune stimulation. nine0003
Focusing on health will increase the child's immunity
Raising an ordinary acute respiratory disease to the rank of an emergency, one can involuntarily suggest to the child that he should be sick. And such a setting gives a negative result. It is reasonable to explain that fever, cough, runny nose are a natural reaction to the virus, nothing terrible happens. You just need to help the body cope with a cold: drink infusions of herbs, potions, steam your legs, if necessary, lie down. At the same time, you can say: "You are already recovering, another day or two - and everything will be fine." nine0003
Why is the topic of immunity especially relevant in spring?
Spring is preceded by winter with its cold weather, reduced solar activity, lack of fresh berries, various vegetables and fruits in the daily diet. Spring is a period of adaptation of our body to other conditions of existence, when it is especially important to pay attention to your immunity. But today, against the backdrop of a pandemic, this problem is becoming even more acute, forcing a person to take their protection, and even more so the protection of their children, especially seriously. nine0003
What is immunity?
In simple terms, immunity is the protection of our body from everything foreign: bacteria, parasites, viruses, fungi, and even cells that have mutated within the body or cells of the immune system that cause autoimmune diseases. So our body ensures the constancy of the internal environment.
Non-specific and specific immunity.
Non-specific immunity is also called innate, as it is some initial indicator of the body's immunity to certain infections; in the first years of a child's life, it is formed thanks to mother's milk. Specific , or acquired, is "acquired" during a person's life and represents a kind of memory of contact with a particular pathogenic infection.
Why do children get sick more often? Peculiarities of children's immunity.
The formation of immunity in children is a long process and consists of several critical periods, most often there are five main ones: up to 28 days of life, up to 4-6 months, up to 2 years, up to 4-6 years, up to 12-15 years.
The immunity of the newborn is the most vulnerable, as it is provided by the mother's breast milk. During feeding, the baby receives not only nutrients, but also protection: antiviral, antiparasitic factors, leukocytes, a number of anti-infectious elements, as well as class A immunoglobulins (IgA are responsible for local immunity: mucous membranes of respiratory organs, cavities, skin). A feature of immunity in the first few days of life is a very high sensitivity to viral infections, since the mother's antibodies do not provide this protection. nine0003
The second period is characterized by the destruction of maternal antibodies and the gradual development of their own. The child's immunity begins to get acquainted with pathogens, but so far without remembering the disease (there is no secondary immune response). The lack of local immunity of this period explains the high sensitivity of the child to many airborne and intestinal infections.
Features of the third period are related to the fact that a child under the age of 2 years becomes more active and inquisitive, socialization begins and the study of everything around. Innate immunity is still imperfect and the process of acquired immunity formation is just starting (antibodies to some viruses are produced and the risk of recurrence is reduced) against the backdrop of a growing threat from outside. According to immunobiological characteristics, most of the children of this age are not ready for kindergarten. nine0003
The immunity of a child in the fourth period already in many respects becomes similar to an adult, but is still vulnerable. A feature of the age of 4-6 years are frequent helminthiases, which causes a high risk of developing allergies.
The crisis of the fifth period is associated with rapid hormonal changes during the puberty of a teenager. The strength of immunity is significantly affected by a decrease in the volume of lymphoid organs. At this age, adolescents show an increased interest in alcohol, smoking and other xenobiotics, many of them engage in sexual activity early. This experience also causes some damage to the immune system, increasing the frequency of viral infections and the risk of developing chronic diseases. nine0003
From the foregoing, it follows that the immunity of a child differs from that of an adult in its immaturity, and this is mostly a matter of time, but factors contributing to its weakening cannot be ruled out.
Rehabilitation. General recommendations.
1. Nutrition. The children's diet should be balanced both in terms of macro- and micronutrients, it is necessary to take into account the specifics of the physiological processes of the child's body, constantly remember that the child grows and it is in childhood that he receives the basics of proper eating behavior, and therefore his health in the future. nine0003
2. Mode of sleep and wakefulness. Compliance with the approximate duration of these periods helps to prevent overwork of the child's body, as well as to balance activity and rest during the day.
3. Microclimate in the family. The atmosphere in the family has a huge impact on the psycho-emotional state of the child. Good relations between parents and their constructive interaction with the child create the most comfortable home environment, form a sense of security. Equally important is the coordination of policies in matters of education, it should be the same on both sides. nine0003
4. Fresh air and physical health. Sports should be age and health appropriate. As an additional physical activity, dancing, gymnastics, and outdoor games are perfect. Regular walks and sunbathing will contribute to the synthesis of vitamin D.
5. Vitamin and mineral complexes. Today, enrichment of the diet with additional vitamins and minerals is a necessity, as there is a pronounced tendency to reduce the nutritional value of food nine0003
What does Artlife offer for children's health?
Discovery Excellent - vitamins, minerals, highly active enzymes, plant extracts. The ideal formula for the physical and psycho-emotional health of the child. Promotes full growth and development, improves cognitive functions, strengthens the immune system.
Lecithin gel with vitamins - lecithin, vitamin D and B vitamins. Lecithin is an energy "motor" that nourishes all the cells of the body and charges them with vigor. nine0003
Funny vitamins - vitamins A, E, D and vitamins of group B. A unique complex without analogues on the market. Available in the form of a gel with multi-colored balls.
MultiMegin - Omega-3 fatty acids, vitamins and lutein - contribute to the harmonious development of all systems of the child's body.
Panbiolact Kids - restoration of intestinal microbiocenosis in children from 3 years old, helps to support the digestive and immune systems during the child's adaptation to kindergarten or school, prevention of intestinal disorders and dysbiosis. nine0003
MultiLise is a new generation metabiotic, a unique drink based on fermented pumpkin puree, lysates, prebiotics and kombucha.