**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 *Perspective Chapter: Emergency COVID-19 Guidelines Impacts on the Human Microbiome… DOI: http://dx.doi.org/10.5772/intechopen.107843*

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 [25–27].
