Natural immunity generally refers to our ability to defend against infectious disease. This is in contrast to vaccine-induced immunity where the immune system is artificially primed in an attempt to “fore-arm” the body against a specific infection.
Natural Immunity is a complex, interactive phenomenon between multiple systems within the human body and the elements we are exposed to, including microbes. Our natural immunity can be divided into the Innate immune system and the Adaptive immune system. The Innate immune system is a non-specific response that allows us to defend against any microbe we come into contact with. In doing so we develop the Adaptive system, which targets specific microbes we come into contact with, fore-arming us with antibodies against these microbes.
Immune system development is thus a lifelong process which starts at conception. At birth the immune system is considered completely developed, although immature or ‘untrained’.
Before birth we are exposed to some microbes via the placenta. The mother’s vagina and skin are home to millions of bacteria, so as soon as the baby travels through the birth canal, exposure to high levels of many species of bacteria begins. Many of these bugs are ‘friendly’, essential even.
The mother has antibodies against the unfriendly microbes she exposes her baby to, which provide some initial protection, (though learned, or ‘adaptive’, immunity from antibodies is but a small part of overall immune defence). The baby receives these antibodies through the placenta before birth and then via colostrum and breastmilk after birth. Colostrum is an antibody- and vitamin-rich ‘first milk’ which serves the purpose of boosting the baby’s immune system at initial exposure to the new environment. It transitions to mature, calorie- and nutrient-rich breastmilk, intended for growth and development, after about the first three days, and breastmilk continues to provide mum’s antibody protection to the baby.
Whilst being exposed to the millions of faecal, skin and respiratory microbes in their new environment, babies are protected by their own powerful inbuilt innate defences, as well as the mother’s adaptive/learned immunity.
Throughout life we are exposed everyday to bacteria, viruses, fungi and sometimes parasites. These exposures cannot be controlled and are in fact necessary for a healthy environment. They also help keep our immune systems nimble.
Our skin, gut, and upper airways are all colonised with many bacteria and viruses which mostly, like the good health workers they are, do no harm. This is a protective ecosystem known as the ‘microbiome’, which has many actions, such as assisting with digestion of food, teaching our immune system to produce specific antibodies and t-cells, and inhibiting the growth of potentially harmful bacteria and viruses.
Examples of Natural Immunity
A healthy body exposed to infectious organisms can learn to produce the specific immune response required during the initial illness. That way when the microbe, or a related one, is re-encountered, our body recognises and eliminates it.
One example is respiratory syncytial virus (RSV), one of many common viruses that we inhale regularly from birth. It can cause sickness ranging from a mild common cold to serious chest infections. Most humans have had their first RSV infection by the age of two years old. Babies are usually protected against illness for about the first nine months by persisting maternal immunity from mum’s blood, and in her milk if breast feeding. This wanes, and from nine months to two years old is the most common time for children to catch RSV.
Another example is a bacteria called meningococcus which can cause a serious brain infection called meningococcal meningitis. Meningococcus is transmitted by exhaled droplets, breathed in by a bystander. Around 10% of people carry meningococcus in their nose and throat at any point in time, and throughout our lifetime we are exposed repeatedly without ever knowing it.
Meningococcal meningitis is rare because our immune systems become efficient at recognising it and producing the immune response needed to prevent illness.
Young children living in poverty who have poor nutrition and high stress often become very sick with infectious diseases. These diseases are uncommon and milder in wealthy places where children are well-nourished with robust immune systems.
As we grow older, or in times of sickness, our immune system weakens and we become more vulnerable to infectious diseases. For example pneumonia has often been referred to as “the old man’s friend” as it commonly brings about a swift death when we have become old, weak and infirm.
An important contemporary example of acquired immune weakness is over-vaccination, e.g. the covid-19 jab program, where immunity has been replaced by immune tolerance of the spike protein. This leads to worsened and more frequent infections, damaged gut bacteria, and other diseases caused by disconnecting the innate and adaptive arms of immunity.
On this topic, an expert testified to a COVID Grand Jury enquiry that the jabs could never improve on natural immunity anyway.
Protecting Against Infectious Diseases
Rather than trying to rid the environment of all microbes, good and bad, the best protection against infectious disease is maintaining optimal natural immunity. This includes good nutrition, adequate sun exposure, regular exercise and good sleep, spending time in nature, and managing stress. This allows our innate immunity to be in optimal condition, able to defend against any new microbe, as well as allowing our adaptive immunity to respond as it was designed to do.
Appropriate medical advice should be sought if worrying symptoms develop such as increasing difficulty with essential activities e.g. drinking fluids, getting up from bed, difficulty breathing, reduced consciousness, immobility, or severe pain. Of course, minimise contact with others when you are symptomatic.
Keeping the above in mind, trust your body and your immune system.
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