The Hygiene Hypothesis - Essay Example

XXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXX The concept of “The hygiene hypothesis” was first mentioned by David Strachan and it states that inadequate exposure of young children to pathogenic microorganisms (e.g. fungi, bacteria, viruses and parasitic microbes) and allergens hinders the normal development of a natural immunity. Consequently, this condition makes an individual to be vulnerable to infectious diseases and allergies. The hypothesis has been put forward as an explanation to the occurrence of many preventable diseases and allergic infections. The following is an analysis seeking to establish accuracy of the hypothesis with the use of a context that features several case studies in the world and the relevant deductions. Accordingly, it is important to note that the immune system develops from repeated attempts to keep off disease from the low level of pathogens found in a normal environment; as such, when the germs invade the body in life threatening amounts, the immune system successfully wards them off. The need for this exposure in developed nations some decades back saw to larger families than today. This is because parents believed that the elder child would expose the younger one(s) to pathogens, hence harden their immunity (Ascherio &Munge, 2007). It has also been observed that children who are taken to baby care institutions are less susceptible to allergies and immune diseases. The research has indicated that, children who had earlier been exposed to measles or hepatitis A are also quite resistant to allergies. Autoimmune diseases are those that the body should be able to naturally protect itself from, as per the hygiene hypothesis. Such include acute lymphoblastic leukemia affecting young people in the developed world. This is a region where young children are less likely to be exposed, and thereby develop the needed immunity. Unconfirmed evidence also links the hypothesis indirectly to autism, suggesting that an immune disease causes it (Lang, et al. 2010). However, extensive research shows that the hypothesis is of more significance to allergies than to immune diseases (Christensen, 2010). Some of the common allergens, i.e. substances that cause allergic attacks, include pollen, dust, hay, household chemicals, synthetic material, pet fur, some foods and some food preservatives. When these come into contact with the body of the allergic person, his/ her system activates the white blood cells in response to the foreign negative stimulus. (These cells normally help us to fight disease-causing microorganisms). Once released, the white blood cells cause an inflammatory reaction (Christensen, 2010). This reaction is exhibited in various ways e.g. itching, swelling, coughing, asthma, sneezing, running nose, tears etc. Asthma is a chronic condition in which the victim, when exposed to allergens, is unable breathe due to blockage of air sacs (alveoli) in the lungs. If no medical attention is availed, patient may collapse or even die. Drugs and inhalers are normally used to control the situation (Christensen, 2010). However, not all scientists concur with the hygiene hypothesis as there is an antithesis to this which is the exposure theory. The exposure theory suggests that the higher the level of exposure to allergens, the more the possibility for allergies incidence. This theory is based on an observation that people living in urban areas have a higher percentage of allergies than their rural counterparts, and they are more prevalent in the developed than the developing world. Modern day people are more allergic as compared to people who lived some centuries back. While this appears at a glance to be true, large portions of the global population prove otherwise, hence the need for a more comprehensive and convincing explanation (Antony et al., 2006). On the other hand, some scholars support the hygiene hypothesis. A health researcher based in Germany, Dr. Erika Von Mutius investigated the hypothesis in the late 1990s. Her assumption was that kids living in the unhygienic and poor East Germany would be more vulnerable to allergies and asthma than those occupying the modernized and tidier West Germany. Her findings by then proved her theory correct. But what she discovered after the fall of the Berlin wall in 1999 left her in utter dismay; exactly the opposite of her proposed theory had taken place, with children from East Germany showing higher resistance to asthma and allergy. On the basis of the new findings, Dr Mutius was now compelled to review her original hypothesis. She was later to state that young humans exposed many other children to build up a stronger resistance to asthmatic allergens, which forms the basis of the hygiene hypothesis. Separate researches show that a pregnant woman's exposure to microbes may protect her child from developing allergies later in life (Fleming & Fabry, 2007). In his research on the British population since the 1960s, David Strachan, found a positive link between the decreasing family size and increase in the rates of hay fever. He also found out that small children from large families were less likely to catch hay fever (Fleming & Fabry, 2007). Modern lifestyles have to an extent decreased our immunity, whereby airtight doors and windows intended to save energy keep off allergens in the house. Use of antibacterial soaps and other disinfectants have aggravated the situation. In his presentation, Marc McMorris, M.D., a pediatric allergist at the University of Michigan Health System says, “We’ve developed a cleanlier lifestyle, and our bodies no longer need to fight germs as much as they did in the past. As a result, the immune system has shifted away from “fighting infection to developing more allergic tendencies” (Fleming & Fabry, 2007). The invention of antibiotics and immunization against such diseases as polio and measles also implies that our immune systems are not as burdened as in the past (Fleming & Fabry, 2007). Indeed, an upsurge of allergic diseases in the developed world has been blamed low infection rates in early stages of life. The hypothesis works in a manner similar to immunization, whereby a child is injected with a mild form of the disease to be prevented; as the immune system wards off these harmless germs, it is strengthened to fight off actual threats in future (Tang, et al., 2008). A Double edged nature of the hygiene hypothesis is evident among some scholars. While the above literature depicts mostly the beneficial side of the hypothesis, it has a dark side in facilitating allergies. This is because, if the immune system does not get exercise fighting pathogens, it assumes an overreactive nature fighting off harmless things e.g. perfume. The result is an allergy. This leaves scientists arguing whether we can have a ‘too clean environment’, an idea first initiated by David P. Strachan over two decades ago. While in modern civilization germs are a despicable feature that needs to be rid of, leading amore sanitary lifestyle may be responsible for an increase in allergies among children. In as much as cleanliness puts disease at bay, ‘excessive’ cleanliness is thought to be responsible for increased asthma and allergy cases especially in the western hemisphere. Pediatrician McMorris advises parents to just let kids be kids. Let them play outside and with friends, and don’t worry about them coming into contact with dirt and germs. They should however be careful with children having life-threatening food allergies (Christensen, 2010). The dilemma is in just how much level of germs, and what type of germs should children be exposed to without subjecting them to direct risk. It is worthwhile to not that, while the hypothesis has been found to be largely true, a study of African-American intercity children in USA showed that those born of both parents with allergies had a 75% probability of being allergic. That sparked a debate as to whether there is a relationship between immunity and heredity, and if so up to what extent as the remaining proportion is acquired (Geurts & Barkhof, 2008). In conclusion, The Hygiene Hypothesis is based on the simple fact that the body’s immunity against disease and allergy can be enhanced by exposure to the causative agents at early stages of life. Some arguments however have been put across against the hypothesis, most notably the exposure theory. This theory proposes that increased exposure to allergens and pathogens heightens infection levels. Ironically, one of its initial proponents was to later disapprove it during a study in Germany. One school of thought also suggests that immunity is partly acquired and partly inherited, but it is difficult to ascertain the proportions in which the two contribute. In holding as true the hygiene hypothesis, one wonders whether it is okay and even healthy to let children wallow in dirt. All in all, the hypothesis is credible more so because it uses the same principle as immunization which has actually subdued obnoxious diseases in the world Bibliography Antony, J.M, Izad, M, Bar-Or, A, Warren, K.G, Vodjgani , M, Mallet, F, & Power C., 2006, “Quantitative analysis of human endogenous retrovirus-W env. in neuroinflammatory diseases”, AIDS Res Hum Retroviruses, 22:1253–1259. 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