Immunity and Infection - Essay Example

? Introduction It is a known fact that the human skin is the largest organ in a human body. Human skin is the outer covering of our body which protects us from dangerous organism in the unpredictable environment we live in .However, the color, texture and appearance of a skin changes according to the climatic condition of a particular region. Skin is not only a covering to our body , but do a lot more than that .We cannot sense things around us, if we were torn out of skin from our body. According to Kids Health(1995) “No matter how you think of it, your skin is very important. It covers and protects everything inside your body. Without skin, people's muscles, bones, and organs would be hanging out all over the place. Skin holds everything together”. As per Defense Soap(2010)“The average person's skin weighs almost 9 lbs., and is comprised of three separate layers: the epidermis, dermis, and subcutaneous tissue”Since skin is in constant touch with outer atmosphere, it has the high potentiality of getting infected in various atmospheric conditions. Human skin is a flora to various bacteria’s, viruses and harmful organisms and hence by nature our skin possesses the ability to fight against infections. In his book, Elston(2009,pg.8)writes that “Bacterial infection remains the most common infectious cause of visit to physicians”. The skin infection can be seen as bacterial, viral or fungal. Skin in a default fashion attack the pathogens present on the skin in order to protect body from any infection. This is the innate barrier to infection which human body possess by birth. The Human Skin as an Organ In all mammals, the human skin is the largest outer covering which surrounds the body from head to toe. Human body is a complex anatomy where in different organs has different function and position to play. Human skin is the largest organ and has various layers to it to protect the body from various dangers in the outer world. As per National Geographic Society (2010) “Skin is our largest organ—adults carry some 8 pounds (3.6 kilograms) and 22 square feet (2 square meters) of it”. Skin is the primary organ which enables the body to sense the outside world from birth to death. Without a skin covering it is impossible for the human body to exist it as we see it today. According to Nemours (2012)“Without skin, people's muscles, bones, and organs would be hanging out all over the place. Skin holds everything together. It also protects our bodies helps keep our bodies at just the right temperature allows us to have the sense of touch “.In every part of the world. People possess skin with different characteristics as in complexion, texture and health. In cold climate, people has skin of white color and hair with golden texture and people in tropical areas has skin of brownish texture and people in African countries have dark or black colored skin . As per Discovery Communications (2000) “Skin is a miracle garment. It's soft, pliable, strong, waterproof, and self-repairing” The human skin and infections Human skin like any other organ of human body encounters with infection in its course of life span. Since human body is in contact with various dangerous environments, the infections faced by skin are numerous. The skin of human is a natural ground for many bacteria’s to thrive and hence there are lots of infections suffered by human related to bodily skin. In his website Tomecki(2000)mentions that “Humans are natural hosts for many bacterial species that colonize the skin as normal flora. Staphylococcus aureus and Streptococcus pyogenes are infrequent resident flora, but they account for a wide variety of bacterial pyodermas”. There are wide varieties of bacteria which generate skin infection among common men. Even hygiene and poor food habits can account to skin infections. Even without infections, a healthy human skin carries a numerous amount of bacterias.According to Stanway(2011)“About 15-40 per cent of healthy humans are carriers of S. aureus, that is, they have the bacteria on their skin without any active infection or disease”. Staphylococci (‘staph’) is the normal kind of bacteria which survives on the skin exterior and mucous membrane of people.Staphylococcus aureus is the one which is responsible for skin diseases among people. Other normal inhabitants are staphylococci, including S. epidermidis, are commensals which can be found on the skin surface of human beings. Even exposure to sun in an exceeding manner can result in skin cancer among normal people. In his book, Dunitz, (1992) states that “Many people believe that sunlight is beneficial to their general well being and despite warning of their over exposure, most of us enjoy relaxing in the sun”. The Body’s fight against infection - Immunity Every human being by nature has the ability to fight against infection and this is called immunity. Some people can have very strong immunity whereas others can possess weak immunity system. In his journal ,Zasloff(2005 , pg 45-50))“In mammals, most antimicrobial peptides appear to be synthesized in epidermal layers above the stem cell layer and accumulate within the superficial layers of the epidermis and on the skin surface”. It is because of human being’s immunity system that they could survive in different climatic conditions and environement. In his article ,Lewis(2010) mentions that “Skin provides protection from foreign invaders in several ways. Apart from the physical barrier, there are specialized cells of the immune system throughout the layers of the skin”. Our body produces a protein called anti - bodies in order to fight with antigens which it’s comes into contact in varying situations. Biologically, the immunity cell produces anti – bodies and trap the antigens in order to relieve the patient from skin infection. The skin of a human being is prone to infection from bacteria, virus, mould and yeast. In his book Ahmad(2010,pg .4)writes that “Over the last decade there have been changes in the epidemiology of fungal infections as well as dramatic improvements regarding antifungal therapeutic options”. If a person is not healthy and hygienic, then their chances of encountering bacteria or yeast infections are high. A person with an unhealthy lifestyle and food habits can also possess skin infection by bacteria or yeast. Some skin diseases can be genetically handed over to the younger generation and such people need to keep extra attention regarding body hygiene and living environment. The Different Infections skin encounters In below sections, different kind of skin infections is being discussed: There are basically four types of skin infection and they are bacterial, viral, fungal and parasitic. i)Bacterial infection – Bacteria is something which is extensively found on every human being skin surface. If these bacteria get down from skin surface to blood then an individual can become ill. In his website ,Brannon (2012)states that “Bacterial skin infections are very common, and they can range from merely annoying to deadly. Most bacterial infections of the skin are caused by two bacteria, Staphylococcus aureus and a form of Streptococcus”. Folliculitis, cellulite, boils,carbuncle Erysipelas are all types of bacterial infection. ii)Viral Infection: Viral skin infections are caused due to the presence of virus on an individual’s skin. Viral can be of common type to rare one. Some of the viral infections found on a human’s body are herpes, warts, measles, and chicken pox and so on. iii)Fungal Infection : Fungal infection is caused due to the growth of fungus on human skin. As per Sushanth(2012) “Fungus in skin affects your skin because it lives in the keratin, a protein that composes your hair, skin and nails”. Fungus can confide in different body parts of an individual and the term also change accordingly for the particular infection. iv)Parasitic infection: Parasitic skin infection can be varied according to the nature of parasite and the organ infected. According to Goldsmid(2005,pg 1-14)“Depending on the species of parasite, this involvement may be transient, the parasite passing through the skin on its migration to the blood stream and so to a specific target organ”. Innate Barriers to infection : Human body possesses certain innate barriers to infection and these barriers are presented in cells and molecules which are present in the human body. These innate barriers have certain characteristics and can be discussed below. The innate barrier has three characteristics and this can be discussed as below: Characteristics of Innate Barriers The innate immune system of our body reacts in a very rapid action. This is because the skin has an auto immune kind of mechanism, called the barriers or through protein or molecules present in the skin cells. The disease carrying organisms known as pathogens are fought over by the cells carrying protein and antigens. This is an automated process where anti- bodied work by default. The skin cells react in the same manner every time it encounters an infection. The body every time utilizes a protein which can determine the pathogens arising from outer environment. Physical barrier the body uses to prevent infection, In the body, skin is the main barrier to prevent bodily infections. A human body is abundant on skin surface with pathogens but these can’t penetrate in to the human body due to thick keratinized layer of the skin. As per Oracle(2008)“Physical barriers prevent pathogens such as bacteria and viruses from entering the body”. When a human faces an accident and get injured then this pathogens can enter the body into the under lying tissues. This is the reason why a personas burned his body to a higher level gets killed by the presence of large amount of pathogens in their body. Smaller the injury, lesser the chance of a person getting killed by infection. The respiratory, urinary and gastrointestinal tracts Innate immunity is often defined as a rapid, first line defense system providing protection against infection. This system functions without prior exposure to the microbe. Human respiratory system is highly exposed to different pathogens in the air. From the nose to bronchioles in the human body, the exposure to pathogens is an undeniable fact. Practically it is not possible to place a thick skin layer on to the bronchitioles in an attempt to avoid respiratory tract infection. Instead of that, the body produces mucus by lining the respiratory tract. This mucus traps the pathogens from the tract and expels them through nose or throat. If the mucus gets viscous then the expelling process gets hampered and it turns into chronic lung infection. According to Sinuswar(2003)“Normally mucus is clear and thin and its primary function is to filter air particles”. In case of urinary tract, the pathogens can be only successful in reaching internal organs like kidney if the flow of urine is blocked. Urine is not a good medium for pathogens to travel as its flow is against the path of pathogens. Only if urinary flow is stopped then the pathogens can enter and infect the kidney. According to NIH(2012)“Infections of the urinary tract (UTIs) are the second most common type of infection in the body”. When it comes to food intake and gastrointestinal infection, the food and liquid consumed is the main culprit. Most part o the pathogens in the food and liquid are killed by the acids produced in the stomach. If at all any organism pass through the stomach and reach bowel, then it has to fight with bacterial living in the intestinal tract. So these are the innate barriers present ion human body in relation with infections. Conclusion All know that skin is the largest organ in the human body and hygiene of skin is the direct way to healthy body .The Human skin is the main platform to the sense of touch and one cannot survive seriously in the absence of touching sense. However the infections found on skin of people are mostly due to the ignorance and unhygienic life practiced by them .The various infections caused by bacteria’s, viruses and fungus can be eradicated if people maintain proper cleanliness. In the website,Bupa(2010)“Fungal skin infections can be spread from person to person. For example, athlete's foot is thought to be spread in communal areas, such as gyms and swimming pools”. However, nature in order to protect human body from infection has applied certain innate barriers which are in action by default. In the website,Cellulitis(2009)“ Bacteria are everywhere around us We cannot get rid of them, nor would we want to because they can be harmless and beneficial for us too.”. But it is our duty to keep our body clean and robust. The most important passage of air, food and water like respiratory tract, gastrointestinal and urinary tract are constructed in a way to fight pathogens naturally. The Human body is organized in such a way that any uncleanliness in the living quality of a person could result in infections. Bibliography Ahmad, I, 2010. Combating Fungal Infections: Problems and Remedy. 1st ed. Heidelberg: Springer Brannon,H. 2012. Bacterial Skin Infections. [ONLINE] Available at: http://dermatology.about.com/od/infectionbacteria/tp/bacterial_infections.htm. [Accessed 30 March 12 BUPA. 2010. Fungal skin infections . [ONLINE] Available at: http://www.bupa.co.uk/individuals/health-information/directory/f/fungal-skin-infections. [Accessed 01 April 12]. Cellulitis.org. 2009. All About Cellulitis Infection. [ONLINE] Available at: http://www.cellutitis.org/. [Accessed 01 April 12]. Defense Soap. 2010. Skin Infections . [ONLINE] Available at: http://www.defensesoap.com/skin-infections.html. [Accessed 30 March 12]. Discovery Communications Inc.. 2000. Human Skin. [ONLINE] Available at: http://yucky.discovery.com/flash/body/pg000146.html. [Accessed 29 March 12]. Dunitz, M, 1992. The Environmental Threat to The Skin. 1st ed. London: Taylor& Francis. Elston, D.M, 2009. Infectious diseases of the skin. 1st ed. London: Manson Publishing Ltd Goldsmid, J, 2005. Parasitic infections of the skin. Primer of Tropical Medicine, 10/2, 1-14. Kids Health. 1995. Your Skin. [ONLINE] Available at: http://kidshealth.org/kid/htb w/skin.html. [Accessed 30 March 12]. Lewis,V. 2010. The immune system and the skin. [ONLINE] Available at: http://ww w.netdoctor.co.uk/skin_hair/skin_immune_system_003741.htm. [Accessed 30 March 12]. NIH. 2012. Urinary Tract Infections . [ONLINE] Available at: http://www.nlm.nih.gov/ medlineplus/urinarytractinfections.html. [Accessed 01 April 12]. National Geographic Society. 2012. Skin. 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Zasloff, M, 2005. Sunlight, Vitamin D, and the Innate Immune Defenses of the Human Skin. Journal of Investigative Dermatology, 125/10, 45-50 Read More