Open access peer-reviewed chapter
Abstract
There have been over sixty microbiome scientific studies involving populations in Europe, Asia and America which have enabled researchers to be able to map the human microbiome. There have been also over hundred publications on the effects of skin cosmetic conditions on the dynamism of the human microbiome. The human body naturally has its own ecosystem of microbiome population which further studies have shown that they are associated and communicate with the human immune system. Recent studies have shown that there are benefits which are derived from a healthy microbiome which is composed of a balanced microbial diversity. Advances in technologies, and increased WHO guidelines due to the COVID-19 pandemic are increasingly being found to be impacting this long-standing human-microbiome synergy. The skin surface microbes and their interactions with other organisms have a significant capacity of influencing health by being immune modulators through either their cell components or other cellular metabolites. This Book Chapter shall discuss and propose microbiome targeted therapeutics strategy as a rationale to involve the role of immune system dynamics and human microbiome in the fight against COVID-19 pandemic and other pandemics.
Keywords
- SARS CoV-2
- WHO
- sanitization
- antibodies
- vaccination
- biota
1. Introduction
There is need to have a universal language on how practitioners can trace and treat the progression of a pandemic. This need has been highlighted by the COVID-19 outbreak. Furthermore, the long-term effects on the immune system need to be investigated. The impact of the WHO guidelines on the immune system should be determined at all ages of the human population as they were postulated to have contributed to the reduction of the spreading of the SARS CoV-2 [1]. This book chapter examines the rationale and impacts of wearing of masks, hand sanitization and social distancing as measures of containing COVID-19. The analysis gives possible advices on retaining a functioning immune system in the midst of contradicting forces. Recent studies have shown the role of microbiome in influencing health as a therapeutic strategy via modulation of the immune system. This modulation occurs through cell components and cellular metabolites.
Although the SARS CoV-2 is regarded as a new contagious corona virus, the human body has encountered, the family of coronaviruses for ages [2]. The common human pet called dog, usually hosts many corona viruses. Even with such advances in knowledge on corona viruses, we are still not sure about the origin of SARS CoV-2. Some speculations of natural SARS mutation or laboratory synthesized virus origins have been suggested.
If the SARS CoV-2 is a new virus, then the human immune system might take time to develop antibodies immediately. However, if it is not new, past ideas from similar virus can be give the body a strategic advantage over the new mutation called SARS CoV-2. This strategic immunity can be related to a possible innate kind of immunity which can provide protection from coronaviruses without the need for a preconditioning of the body from the current new virus in the environment. The need for a new diverse vaccine can also be argued on the same understanding. Various people will react to SARS CoV-2 exposure mainly depending on how their bodies respond to inbuilt immune defenses against specific past exposures on corona viruses. An individual health and locational responses to corona viruses can determine the outcome of the health status of an exposure. However, this expectation is not as straight forward as we expect if the SARS CoV-2 is a man made and new inserted genome sequences of a synthesized corona virus. The adaptability of the immune system can also circumvent the human induced mutation as it has been doing before naturally.
The joint ecosystem between the human body and microorganisms is referred to as holobiont. It is made of persistent microorganism communities [3]. At the cell level our bodies are also interacting with microorganisms. This interaction has physiological impacts in development, immunity, adaptation and general health. This microecology is maintained at particular balance because disturbance of their equilibrium can cause diseases. The microorganisms in our bodies have been found to be transferable from one body to another. A host and its microbiota constitute a holobiont [4]. This phenomenon has become more important in the spread of COVID-19 and the place and value of the immune system health. This microbiome has the ability to remain silent until when disturbed. Microbial activity is necessary for life on earth. The microbiota composition in humans in built in the early years of a new born before reaching a more stable adult-like configuration at the age of ~3 years [5, 6, 7]. Henceforth, studies have shown that the host-microbiota equilibrium in humans is important and that a perturbation of such homeostasis may lead to shifts from healthy to pre-disease and disease states [8]. It is amazing how diseases like obesity, which is lifestyle related can be linked to microbiome dynamics. The shift from a healthy microbiota to pathobiota is influenced by modern civilization which does not consider its impact on the microbiome [9, 10]. Therefore, the holobiont concept highlights the complexity of host–microbiota interactions as a challenge and as a new venture for research for the scientific community [11, 12].
2. The immune system and the microbiota
In a broad sense, we have the adaptive and innate immunity. The body has a mechanism that enables living organisms to distinguish its own cells and substances or humors from foreign ones. This ability is called adaptive immunity. It has the ability to generate a specific cellular response to new pathogens [13]. The innate immune system is made up of cells and organs which are distributed throughout the body. The blood and the lymph usually distribute the immune cells throughout the body. The Innate immune cells react fast and nonspecifically when foreign cells are detected. The adaptive immune cells usually have a delay in their response. However, they later end up forming specific immunological memories of the intruding proteins. Researchers have suggested several ways to boost the immune system. These include the following three ways; The increase of immune system cells circulation to do their functions by doing moderated exercises to increase blood circulation, The boosting of the endocrine system functions by reducing stress and thirdly by eating balanced foods that are rich in vitamins and minerals [14]. The interactions between microbiota and host immunity are complex, dynamic and context-dependent [15].
3. Diseases and the microbiome
Diseases that affect humanity mostly thrive on a dysregulated or disturbed immune systems. Human beings have over the years developed mechanisms to coexist with microorganism [16]. Furthermore, this microbiome inhabitants are in constant interactions with the immune system either on the body surface or on the inside. The role of this human-microbe interaction is to train and empower the immune system [17]. In other words, the human body produces natural antimicrobial substances like tears, saliva, mucus and acids that inhibit or kill pathogens. These natural are supposed to be maintained for the proper functioning of the body immune system. Surprisingly, the same pathogens are the ones which stimulate the body to produce these useful antimicrobial substances. The phenomenon has helped the immune system to be maintained strong. There are critical roles which the microbiome plays in the training and development of the host’s innate and adaptive immune system major components [15].
4. Microorganisms’ role in training and boosting the immune system
In general, adaptive immunity is described as a mechanism that enables living organisms to distinguish its own cells and humors from foreign ones. It then generates a specific cellular response to the new pathogen [13]. The Immune cells in the body are distributed throughout the body by the blood and the lymph. In comparison, the innate immune cells usually react fast and are nonspecific when foreign cells are detected. The adaptive immune cells usually have a delay in their response, however, they end up forming a specific intrusion protein immunological memory.
If we carefully assume that the SARS cov-2 is natural mutation of the SARS corona virus then we can trust the human body to fight and overcome its invasion. However, a human synthesized source can be different. We can try to envisage the effects of the inserted sequences by the symptoms and signs from patients or from the sequences bases available. In our studies we assume that the immune system is not being influenced by other environmental factors causing similar symptoms. However, we are aware of major emerging environmental factors like climate change and human factors including chemical pollutions, nano particles or electromagnetic waves including mobile phone radiations.
Ref., [14], showed that the immune system can be boosted via reduction of stress, eating of balanced diet inclusive of vitamins and minerals. There are other ways of increasing the capacity of the immune system like doing moderate exercises which make the distribution of immune system cells to be faster and wider. A disturbed and dysregulated immune system have been shown to be the ground for diseases to be established in humanity. The earth biosphere is full of microbes as shown in Figure 1. Living bodies have over the years developed mechanisms to enable them to coexist and survive in the midst of microbes [16]. These microbes interact with the immune system on various levels. It can be very specific or non-specific. These interactions are very important in strengthening and training the immune system [17]. Furthermore, there is growing evidence of microbes influencing the peripheral cells of immune and thus consequently influencing cells at other distal sites [18].
Figure 1.
The expected microbiome equilibrium around homes, and markets. It is worthy to note that each location has its own unique microbes which are also constantly being invaded by other microbes from other places and individuals. However, a new equilibrium is usually established after sometime due the law of the survival of the fittest due to competition or due to factors that enhance aggressive adaptation in changing environments.
5. The microbiome acting as a layer of defense
The normal body flora is composed of large community of microbes which associate with body cells. The association can be on the surface of on internal organs like in the digestive system. The layer of microbes can act as a physical barrier for cells and reduces the available surface for intruding pathogens. It also increases their survival competition, see.
Figure 2, The human microbiome is furthermore reinforced by the production of natural antimicrobial substances that act by inhibiting or killing invading pathogens. These natural body antimicrobial substances in animals include tears in eyes, saliva in the mouth, mucus in the respiratory surface and acids in the stomach. The body has to be stimulated to produce these useful antimicrobial substances. This is in many cases done by the same or similar pathogens. This scenario is developed and maintained continuously and is very important for the strengthening of the immune system. Pathogens that mutate have to fight the same microbial defense barrier. The body is only diseased if microbes overcome and pass this barrier.
Figure 2.
The scenario of an invasion new microbes like in the current situation; the immune system is being attacked by the novel SARS CoV-2. The body will try to develop a new equilibrium. This is usually done easily and effectively if human external factors and extreme mutations in gene sequences are not added.
6. Relooking at the WHO guidelines
Three main COVID-19 guidelines were issued by the world health organization (WHO) in the fight against the novel SARS CoV-2. One of them was the proper handwashing of hands. This is based on the idea that the coronavirus is killed by proper handwashing of hands for 20 seconds with soap or by using hand sanitizer that has an alcohol concentration of more than 60%. The microbial envelop is assumed to be effectively being affected by the soap.
7. The implications of washing hands on the immune system
Normally, the human hand has a high concentration of microbial community. However, studies on the hand microbiome showed that there are some factors that can impact the hand microbiome composition. These factors include, temporal and biogeographical changes, age and intrinsic gender. Others are extrinsic product use, extrinsic cohabitants and extrinsic pet-ownership variables. Further studies have shown that the hand microbiome is always in constant changes. Therefore, hands are a critical factor in transmitting microbes between people, animals, inanimate objects and our environments see Figure 3). This transmission and establishment of microbes stimulates our immune system and prevents harmful microbes from colonizing the hands. Consequently, the WHO guideline seems to be enhancing the reduction of hand microbes and can contributing to the weakening the immune boosting abilities and opening the hand to new pathogens including novel viruses like SAR CoV-2. Washing hands with a sanitizer also makes it more difficult for the normal body flora to reoccupy their habitats due to changes of pH. It is like a reset of the microbiome. The touching eyes, skin, nose and mouth and other body parts after touching other places and people assist in boosting the strength of the immune system as a natural process.
Figure 3.
The continuing wearing of face masks reduces the distribution of natural microbes to other places. Keeping interactive social distancing reduces the transfer of natural microbes from one person to another and from one region to another. This transfer of microbes from one source to another is crucial for the training and development of the immune system in children and boosting and strengthening the same immune system in adults. The current invasion of SARS CoV-2 into an intact and dynamic microbiome and its establishment is not possible. However, these studies show that it can be reinforced by a systematic destruction of the microbiome community or by having a novel synthetic virus which is more aggressive.
8. The implications of social distance on the immune system
The maintenance of social distance or physical distance of at least 1 metre (3 feet) distance between one person and another has been used as a measure of preventing the spread of SARS CoV-2. This was to reduce the spray of contaminated droplets from nose and mouth to uninfected people. Moreover, people with symptoms like coughing, headache and fever were advised to self-isolate. However, the implication of the social distancing practice is that there shall be little person to person exchange of microbes. This if practice is coupled with the washing of hands and continuous sanitizing shall make it very difficult to recover the normal flora populations. This shall be another reset of normal body flora. It shall cause a weakening of the immune system and might most likely open an opportunity for new pathogens to attack the body including making the new SARS CoV-2 more virulent. Furthermore, in the face of the global climate change and increased migrations we might end up with a reset of the current human microbiome population.
9. The implications of wearing face masks on the immune system
In another the precaution of wearing face masks in crowded places is not natural to the body. It can increase mental stress in the body on people who are already bombarded with economic burden and frequent pandemic information. Immunological studies show that stressed bodies might have malfunctioning of the endocrine system and the weakening of the immune system. The use of a mask increases the intake of the respiratory carbon dioxide from the body which makes metabolism to be lower. This affects negatively people with other under laying conditions like diabetes, mental health and high blood pressure.
10. Discussions and conclusions
The diversity, abundance and functionality of the microbiome is still being deciphered. It is worthy to note that the microbiome role in health is of paramount importance. Much studies on microbiomes and microbiota have been done in bacteria. Less studies have been done in fungi, with only less than 400 fungal species so far having been isolated [19, 20, 21].
The training and development of the host immune system is promoted by natural body and environmental microbes. These interactions have been occurring to keep invading pathogens at bay. Some of these microbes are commensals and hence they promote the development of the immune system B cells that assist the body to produce Immunoglobulin A (IgA) which is a protective antibody. The role of the IgA is to neutralize pathogens and exotoxins. This promotes the development of the immune system. Deviations from this natural mechanism can have short term effects but after sometime it can produce new waves of disease out breaks and pandemics. The natural microbiome populations have been known to prevent the growth of harmful pathogens by using various parameters like altering pH, effectively consuming nutrients required for pathogen survival, and by even secreting toxins and antibodies that inhibit growth and competition of pathogens [16].
This Chapter has examined some of the potential effects of WHO guidelines in relation to microbiome and the human immune system. Suggestions have been made on how to have a balance between having a healthy immune system and not exposing it to pathogenic attacks when weakened. Microbes have a significant capacity in influencing health by being immune modulators through either their cell components or other cellular metabolites including hormone production. We propose the development of microbiome targeted therapeutics strategy in order to involve the role of immune system dynamics in the fight against COVID-19 pandemic (Figure 4).
Figure 4.
The effects of the WHO guidelines of social distancing, sanitization of hands, streets and markets and homes is gradually reducing the protective microbiome barrier in human populations. The invasion of SARS CoV-2 into an intact and dynamic microbiome is being reinforced by destroying the microbiome community if a synthetic and more competitive, mutating virus which destroys the immune system is introduced in the equilibrium. This can lead to another pandemic due to the altering, replacing or editing the time proven human-microbiome interactions.
11. Impact of WHO guidelines on COVID-19 to the immune system
The COVID-19 outbreak caused the world health organization (WHO) to issue three major guidelines in the fight against the spread of the novel SARS CoV-2. These were washing of hands, wearing of masks and keeping physical distances. Careful examination of each of these guidelines show that they have a negative effect on the immune system.
The sanitization of hands or hand washing was based on the idea that the SARS CoV-2 was killed by proper hand washing for 20 seconds with soap or by using an alcohol-based hand sanitizer of more than 60% concentration. However, the implications of this washing hands guideline to the immune system are that the human hand which has a high amount of microbial abundance and diversity was being transformed to another composition gradually. Studies have shown that there is an intimate relationship between microbiomes and the immune system that requires a healthy host immunity to prevent commensals from overexploitation of the host resources while maintaining immune tolerance to innocuous stimuli [22, 23]. The hand microbiome is influenced by temporal and biogeographical dynamics, intrinsic age, intrinsic gender and extrinsic product use, extrinsic cohabitants and extrinsic pet-ownership variables. This microbiome is constantly changing as the hand involved in transmitting microbes between people, objects and environments. This transmission is crucial in stimulating the immune system and preventing harmful microbes from colonizing the hands. However, the WHO guidelines of sanitizing the hands just because of one virus has the potential of weakening the immune boosting abilities and opening the hand to new pathogen colonization. This could actually be the virulent SARS CoV-2 itself. Furthermore, the washing of hands with a sanitizer makes it more difficult for the normal body flora to reoccupy their natural habitat because of the new pH.
The second WHO guideline of keeping a physical distance of about 1.5 m between one person and another. This regulation is based on the idea that if somebody coughs or sneezes, the droplets with the virus will not be able reach the nose of another person. People are also advised to stay home and to self-isolate when they notice symptoms like coughing, headache and fever. This means that shall be little exchange of microbes from one individual to another. Therefore, if all these guidelines are implemented it might be very difficult to recover the normal microbiome of healthy individuals. Could this trigger a bigger pandemic?
The third major WHO guideline is the wearing face masks in crowded places or if one would like to go out so as to avoid infecting others. The idea is that contaminated droplets shall not be able to find their way to other people or land on surfaces to contaminate them. The wearing of masks is not natural to the body. This can stress the body who are already under economic and social burdens. This stress can impact the endocrine system and the immune system. This is more so on old peoples and people with chronic illnesses like diabetes. The later studies did sent caution that people with underlying conditions should not be vaccinated.
Studies have shown that human disease and therapeutic interventions affect microbial communities’ abundance, diversity and functionality [24]. There are two drivers of the human microbiome composition: one is the genetic and immunological factors and two is the environmental, notably diet and environmental biodiversity. Human beings display a substantial loss of microbiome in comparison to chimpanzees and gorillas. This loss is attributed to much diet modification and environmental changes [25, 26, 27].
12. Microbiome-immunity crosstalk mechanisms and COVID-19
The microbiome is composed of a great number of microorganisms which in the human body are found in the gut and also on the skin and other mucosal microenvironments. Studies have shown that microbiome is active participant in a host functions like immunity and other metabolism activities. Other functions which have a microbiome impact are nutrition end products and the circadian clock operation [28, 29, 30]. Studies have shown that lung microbiome can modify the risk and consequences of COVID-19 by activating the immune response. On the same line, other suggestions show that bacterial co-infections as well as the gut-lung cross talk may be important players in COVID-19 disease prognosis. Recent studies have established that COVID-19 patients with GI complications experience more respiratory distress when compared to the patients without GI complications [31, 32]. Interestingly, obesity,
13. Recommendations
The recommendations from this crucial evaluation of the immune system role of the microbiome is that in future we should not over look natural mechanisms which have established an equilibrium with the immune system. This should also involve the educating of masses on how to cultivate the natural human microbiome defense systems as physical barriers. The training and boosting of the immune system both in children and adults respectively should regionally be evaluated. This is because increased traveling and climate change cannot be assumed to be of little consequences in pandemic control strategies in light of the microbiome roles.
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