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出门在外也不愁6 Things I Wish I Knew Before Moving to a New Country by Myself
Moving abroad is an incredible opportunity, but be prepared to face some challenges.
So you have your suitcases packed and your guide book ready. You've triple-checked that you do indeed have both your plane tickets and your passport -- and will maybe check one more time... just in case. You're off to live in a new country for the first time in your life and you could not be more excited..
Cling to that excitement as tightly as you can, because moving out on your own is a big step anywhere, but even more so when you add in oceans and other continents. Whether you're venturing out for a new job, , or giving back to the greater good as a , the following pointers are good to keep in mind. As soon as the panic (inevitably) hits and you breakdown in a spectacular manner, take a moment to breathe and then follow these steps.
Full disclosure, I'm a diplo-brat and grew up moving from country to country. This was all with government support. I did not realize how invaluable this support was until I ventured out on my own. This article may wash away some of that bright-eyed optimism but will also leave you with a more realistic blueprint of how your first few months abroad will go. Take deep breaths, this will only hurt a little.
1. Securing Housing Should Be Your Top Priority
You're in a new country. You're homeless. That local hostel, hotel, or friendly couch will only keep you for so long before you need a (somewhat) more permanent abode. I know you think it'll be easy to find a fantastic apartment in the big city, close to all of the major sights and with a steal-of-a-rent, but this isn't realistic. Those places are more expensive, and you may have to be flexible on where you live to find a place within your budget.
Embrace the surroundings
To find housing on your own, you could find a real estate agent (which is, admittedly, a bit of an old school tactic), check classifieds, talk to other expats (nothing like a personal recommendation!), or use one of the many online housing providers out there. Yes, the big name in the industry, AirBnb, will let you rent places by the month -- but's not the most economical.
Other services are specifically catering to folks who want to stay longer -- say, 6 - 9 months longer -- and are ideal for students, teachers on a shorter contract, or for those of you who want more time before you commit to a place.
are two Europe focused examples of housing providers.
When searching for an apartment, keep in mind these basic tips:
Your first (and sometimes second) month of rent as well as a security deposit will be required when you sign your lease. Figure out ahead of time if you'll be able to write a check from your home bank account, if you can even withdraw that amount of cash, or if there's another way you can pay. Usually a phone call to your local bank asking them to temporarily lift a withdrawal limit is enough to get the cash out of your checking account.
Be sure to have enough savings to cover these upfront costs without resigning to Ramen til your first paycheck.
Don't forget about the mundane, yet essential, tasks of figuring out your water, electricity, trash, and internet.
Try to have a local help you organize your housing, especially if there's a language barrier. Their insider's perspective will prove invaluable, and help you avoid potential scams for extra fees ("Foreigner's tax," if you will), that you're in a good neighborhood, and ensure there's no funny business in your contract. If this local is a personal friend who genuinely cares about you, even better!
Whatever you decide, don't ever use Craigslist to find apartments. Bad things will ensue, I promise. No matter how friendly that upstanding citizen seems online, do not send them your money. They will try to convince you that the ridiculously low rent they are charging is because they want a trustworthy caretaker. Nothing is free in this world, especially on the internet.
I know you think that it'll be easy to find a fantastic apartment in the big city, close to all of the major sights and with a steal-of-a-rent, but this isn't realistic.
If you're determined to find an apartment on your own, then I would recommend searching through an expat forum. Depending on the country, long term house-sitting may also be an option.
both list house sitting opportunities internationally.
There are a ton of people who own property but only use the houses or apartments for a week or two a year. The rest of the time they need someone to rent it to. There are other expats vacating apartments as they move on, so you might get the inside scoop without slogging through the scams.
2. Making New Friends is Tough!
Now that you have a nice, cozy apartment, you're starting to want someone to share in your adventures. The problem is, you don't have the faintest idea where to find that someone.
Find friends with similar interests
During your time in high school and college, having a group of friends was relatively easy. You were all the same age, participated in the same activities, and grew up in the same area. You had classrooms and daily interactions to turn strangers into friends. Chances were that you never really had to search for a buddy or two, beyond those initial "Will you be my friend?" conversations we all had in kindergarten.
This is different. you're out in the real world and
means taking on a whole new approach to friend making. you're not really a vagabond, so the whole backpacker scene is not for you. If you're working at a company or school, then your friends will likely be your new coworkers.
If not, then the whole "friend thing" becomes a lot more complicated. You don't want to live in your Facebook past but you're unsure of how to continue in your overseas future.
Before you retreat into a cavern of loneliness and despair, give these following tips a try:
Give online friends a whirl. Bloggers are great people to know and tend to be in touch with their community. Do a quick search for people writing about your area and see if you can arrange to meet for coffee. Check for local meetups, expat get-togethers, or Couchsurfing events. Of course, make sure to meet up in public areas the first couple or times.
Join a local organization. Do you like to cook? Ride bikes in crazy hot weather? Climb ridiculously early in order to capture that perfect sunrise? There will be communities of expats and locals who feel the same way. Find a group online with similar interests.
Learn the local language with a language partner. See if there are local
that host a language exchange, or search for established ones online.
Join an online expat organization. There is comfort in familiarity and while you're on a grand overseas adventure, it can be wonderful to talk with a group of people from your home country. There are a ton of expat groups online and they tend to organize gatherings and get-togethers.
Take a class in something you're passionate about. Whether it's cooking, language, or dance, you're sure to meet people who have similar interests as you.
3. Pay Careful Attention to Your Relationships Back Home
Now that you have both a fabulous pad and a group of bosom buddies, you want to share the great news with your loved ones back home. With Skype, Facetime, Snapchat, and a whole host of other platforms, there's no way that you'd ever drift apart from anyone, right?
Make sure you know how to get around
Please rid yourself of this idealism immediately. it'll save you a lot of heartbreak and frustration. Keeping in touch takes a lot of effort, even without the added difficulty of translating through a new cultural lens. While you happily burble on about the fantastic roast duck at a hole-in-the-wall restaurant down the road, your friends and family back home will be nodding in polite interest.
There will be an initial period of excitement over your new lifestyle, but it'll fade. Your lives are on very different trajectories and it can be hard for some people to understand what they have never experienced.
Here are some tips to forestall and minimize any potential friction:
Be patient and understanding. This goes for . While you, the intrepid traveler, should be able to express your new life, you should not monopolize the conversation. Your friends and family may be going through a different stage in life and their daily doings matter too.
Try not to be arrogant. I'm sure that you're not deliberately flaunting how much more awesome your life is than those of your friends and family, but it may come off that way.
Make an effort to schedule a specific time to Skype, or at least make sure you know the time differences well enough so that you're not calling at ridiculous hours.
Keeping in touch is a lot of effort, even without the added difficulty of translating through a new cultural lens.
4. Transportation and Foreign Bureaucracy are the Devil
Apartment, check. Friends, check. Strong ties back home, check. Now that you have the basics down, all you need to figure out is how to live in this new country. Keep in mind that there are many countries whose government offices move at a slower pace. This is when you learn patience, young grasshopper.
You'll want to do a victory dance the first time you navigate public transit independently and successfully. It can be a daunting task, familiarizing yourself with all of those zillions of bus routes, carrying correct change in foreign currency, or buying a ticket from the automatic dispenser, with instructions written in what might as well be gibberish.
Keep these tips in mind as you traverse your new home:
Be sure to have your visa in order. Know where the government offices are and know how long a wait each appointment requires. Most importantly though, bring a book, try not to get frustrated at all the red tape, and celebrate with your new friends when it's all over.
Mastering the local transportation will help you immensely. Metro, bus, taxi, rickshaw, biking -- all of these are important to learn. See if you can purchase a monthly pass or whether you will need to buy a new ticket for every trip. Buy a helmet if motorcycle-taxis are the best way to get around, and definitely make sure that these are safe modes of transportation.
The flow of traffic is extremely important. You need to know whether or not the cars will stop for pedestrians or if you will have to play a complicated game of survival every time you cross the road. Especially if you're on a moped or motorcycle, pay attention to how everyone else drives, and do as they do.
You're off to live in a new country for the first time in your life and you could not be more excited. Cling to that excitement as tightly as you can because the next few steps of moving abroad on your own will challenge you immensely.
5. Mastering Different Cultures' Etiquette Norms Takes Time
Immerse yourself in the local culture
Don't be too afraid of being the
-- at least at first. You'll make mistakes, of course, but as long as you exercise a bit of common courtesy, read up on some basic etiquette, and channel those manners that you only used with your grandparents and you should be fine. That being said, there are some cultures that are more finicky than others.
In order to keep the peace with your neighbors, follow these tips:
Figure out any specific ways you might offend the locals, and avoid them! Depending on where you are, it may mean not eating with your left hand, showing the soles of your feet, or sticking chopsticks vertically into a mound of rice.
Learn how to greet people and how to share a meal. These are two of the most important lessons you will pick up abroad, and will likely even get you a few new,
to share with your friends back home.
Look up the local holidays. This will help you navigate the cultural landscape of wherever you live. Having a list might even warn you about impending non-stop fireworks, massive water fights, or celebrations filled with colored powders.
Whatever you do, no matter how disgusting a gift of food or drink it may look, never make a face or refuse it. If I can down yak butter tea, so can you.
6. A Program Can Help You Organize Upfront Logistics
and making new friends can be scary enough on its own, without the hassle of organizing housing, finding a way to support yourself, and dealing with bureaucracy. Sometimes, the best way to spend an extended period of time abroad is to go through a program.
Consider signing up for a
or heading to a foreign country for an extended
stint. This might be the best of both worlds: your program with help out with all of the logistics, and you'll have plenty of time abroad to immerse yourself in a new culture.
There are many programs that can help you get standing on your own feet and ease your transition to life in a foreign country (which may cost you more up front, but will save you a ton of headaches and frustrations). Organizations like , , and
are established in a wide variety of countries.
If you're even slightly interested in studying a language abroad,
is a good place to start your search. Though, of course, these organizations are by no means the only program providers out there!
A Few More of Our Favorite Programs
Key Takeaways
Real estate agents are the best, always have starter funds, and don't forget electricity, water, trash, and internet.
Try an expat forum as an alternative to getting a real estate agent. They will either own property to lease or will be newly vacating a prime piece of real estate.
Make friends abroad by meeting with bloggers you find online, joining local groups, finding a language buddy, or joining expat groups.
Stay in touch with friends and loved ones back home by using technology. Make sure you have a schedule, a clear understanding of time zones, and a dash of humility.
Figure out the local transportation system and make sure that you have all of your paperwork in order for the local government.
Bond with locals by not offending them, showing an understanding for their customs and participating in their holidays.
Consider seeking an organization or soliciting the help of long-time expats to help you get your life abroad off the ground.
Making the decision to move abroad on you own is an enormous step. It's the perfect opportunity to explore the world, get to know another city, and foster your own independence. Moving abroad will definitely be a challenge, but with the right planning it's completely possible and totally worth it. Follow these tips and you'll have a totally new life in an awesome country abroad in no time.
Read next: .
Photo Credits:
By API Study Abroad
Authored by
Go Overseas Writer
Cecilia is a Third Culture Kid who is currently based in Florida. She hopped on her first plane when she was three months old and has yet to stop flying. She has lived in China, India, the U.S., the Philippines, and Turkey. After saving money by working as an English instructor in Hong Kong for a year, she backpacked around the Tibetan Plateau, western China, and northern India. Follow her adventures on her blog, on on Google+, and on Twitter @unsettledtck.
Related ArticlesFrom Wikipedia, the free encyclopedia
This article needs more
or relies too heavily on primary sources. Please review the contents of the article and
if you can. Unsourced or poorly sourced material may be challenged and . (January 2014)
In medicine, the hygiene hypothesis is a
that states that a lack of early childhood exposure to infectious agents,
microorganisms (such as the
increases susceptibility to
diseases by suppressing the natural development of the . In particular, the lack of exposure is thought to lead to defects in the establishment of .
The hygiene hypothesis has also been called the "biome depletion theory" and the "lost friends theory".
The original formulation of the hygiene hypothesis dates from 1989 when David Strachan proposed that lower incidence of
in early childhood could be an explanation for the rapid 20th century rise in allergic diseases such as
It is now also recognised that the "reduced microbial exposure" concept applies to a much broader range of chronic inflammatory diseases than asthma and hay fever, which includes diseases such as
and multiple sclerosis, and also some types of depression and cancer.[]
In 2003 Graham Rook proposed the "old friends hypothesis" which seems to offer a more rational explanation for the link between microbial exposure and inflammatory disorders. He argues that the vital microbial exposures are not colds, influenza, measles and other common childhood infections which have evolved relatively recently over the last 10,000 years, but rather the microbes already present during mammalian and human evolution, that could persist in small hunter gatherer groups as microbiota, tolerated latent infections or carrier states. He proposes that we have become so dependent on these "old friends" that our immune systems neither develop properly nor function properly without them.
Strachan's original formulation of the hygiene hypothesis also centred around the idea that smaller families provided insufficient microbial exposure partly because of less person to person spread of infections, but also because of "improved household amenities and higher standards of personal cleanliness". It seems likely that this was the reason he named it the "hygiene hypothesis". Although the "hygiene revolution" of the nineteenth and twentieth centuries may have been a major factor, it now seems more likely that, although public health measures such as sanitation, potable water and garbage collection were instrumental in reducing our exposure to ,
and so on, they also deprived us of our exposure to the "old friends" that occupy the same environmental habitats.
The rise of
in young people in the developed world was linked to the hygiene hypothesis.
Some evidence indicates that
is correlated to factors (such as certain ) that are indicative of an immune disease. One publication speculated that the lack of early childhood exposure could be a cause of autism.
The risk of chronic inflammatory diseases also depends on factors such as diet, pollution, physical activity, obesity, socio-economic factors and stress. Genetic predisposition is also a factor.
Although the idea that exposure to certain infections may decrease the risk of allergy is not new, Strachan was one of the first to formally propose it, in an article published in the
(now the BMJ), in 1989. This article proposed to explain the observation that
and , both allergic diseases, were less common in children from larger families, which were presumably exposed to more infectious agents through their siblings, than in children from families with only one child.
The hypothesis was extensively investigated by
and has become an important theoretical framework for the study of chronic inflammatory disorders. It explains the increase in allergic diseases that has been seen since industrialization and the higher incidence of allergic diseases in more developed countries. Epidemiological studies continue to confirm the protective effect of large family size and of growing up on a farm. However, exposure to common childhood infections such as chickenpox or measles is not thought to be protective.
The "old friends hypothesis" proposed in 2003 may offer a better explanation for the link between microbial exposure and inflammatory diseases. This hypothesis argues that the vital exposures are not common childhood and other recently evolved infections, over the last 10,000 years, but rather microbes already present in hunter-gatherer times when the human immune system was evolving. Conventional childhood infections are mostly "" that kill or immunise and thus cannot persist in isolated hunter-gatherer groups. Crowd infections started to appear after the
revolution, when human populations increased in size and proximity. The microbes that co-evolved with mammalian immune systems are much more ancient. Humans became so dependent on them that their immune systems can neither develop nor function properly without them.
Rook proposed that these microbes most likely include:
Ambient species that exist in the same environments as humans
Species that inhabit human skin, gut and respiratory tract, and that of the animals we live with
Organisms such as
(worms) that establish chronic infections or carrier states that humans can tolerate and so could co-evolve a specific immunoregulatory relationship with the immune system.
The modified hypothesis later expanded to include exposure to
bacteria and parasites.
“Evolution turns the inevitable into a necessity,” this means that the majority of mammalian evolution took place in mud and rotting vegetation and more than 90 percent of human evolution took place in isolated hunter-gatherer communities and farming communities. Therefore, the human immune systems have evolved to anticipate certain types of microbial input, making the inevitable exposure into a necessity. The organisms that are implicated in the hygiene hypothesis are not proven to cause the disease prevalence, however there are sufficient data on lactobacilli, saprophytic environment mycobacteria, and helminthes and their association. These bacteria and parasites have commonly been found in vegetation, mud, and water throughout evolution.
Multiple possible mechanisms have been proposed for how the ‘Old Friends’ microorganisms prevent autoimmune diseases and asthma. They include: 1. Reciprocal inhibition between immune responses directed against distinct antigens of the Old Friends microbes which elicit stronger immune responses than the weaker autoantigens and allergens of autoimmune disease and allergy respectively. 2. Competition for cytokines, MHC receptors and growth factors needed by the immune system to mount an immune response. 3. Immunoregulatory interactions with host TLRs.
The "microbial diversity" hypothesis, proposed by Paolo Matricardi and developed by von Hertzen, holds that diversity and turnover of bacterial species in the
and other sites is a key factor for priming and regulating the immune system, rather than stable colonisation with a particular species. It is not clear whether diversity per se, or that a diverse population will include certain organisms without which the immune system fails to develop. Rook likened the embryonic immune system to a computer that contains programmes but little data. During gestation and infancy exposure to diverse organisms builds a "database" that allows the immune system to identify and respond to harmful agents and normalize once the danger is eliminated.
For allergic disease, the most important times for exposure are:
la and the first few days or months of infancy. Exposure needs to be maintained over a significant period. This fits with evidence that delivery by
may be associated with increased allergies, whilst breastfeeding can be protective. The extent to which exposures need to be maintained after infancy and whether these conditions could be managed by on-going exposure is as yet unknown.
Humans and the microbes they harbor have co-evolved for th however, it is thought that the human species has gone through numerous phases in history characterized by different pathogen exposures. For instance, in very early human societies, small interaction between its members has given particular selection to a relatively limited group of pathogens that had high transmission rates. When societies became larger, the introduction of agriculture some 10,000 years ago made the spreading of new pathogens more likely, and thus exposures to pathogens that favored high population densities to thrive. Furthermore, pastoralism has made zoonotic pathogen transmissions even more favorable. It is considered that the human immune system is likely subjected to a selective pressure from pathogens that are responsible for down regulating certain alleles and therefore phenotypes in humans, the thalassemia genes that are shaped by the Plasmodium species expressing the selection pressure being a model for this theory.
Recent comparative genomic studies have shown that immune response genes (protein coding and non-coding regulatory genes) have less evolutionary constraint, and are rather more frequently targeted by positive selection from pathogens that coevolve with the human subject. Of all the various types of pathogens known to cause disease in humans, helminthes warrant special attention, because of their ability to modify the prevalence or severity of certain immune-related responses in human and mouse models. In fact recent research has shown that parasitic worms have served as a stronger selective pressure on select human genes encoding interleukins and interleukin receptors when compared to viral and bacterial pathogens. Helminthes are thought to have been as old as the , suggesting that they may have co-evolved, also implying that our immune system has been strongly focused on fighting off helminthic infections, insofar as to potentially interact with them early in infancy. The host-pathogen interaction is a very important relationship that serves to shape the immune system development early on in life.
Allergic conditions are caused by inappropriate immunological responses to harmless
driven by a -mediated immune response, TH2 cells produce ,, ,
and predominantly . Many
elicit a -mediated immune response, which down-regulates TH2 responses. TH1 immune responses are characterized by the secretion of pro-inflammatory cytokines such as , , and . Factors that favor a predominantly TH1 phenotype include: older siblings, large family size, early day care attendance, infection (TB, measles, or hepatitis), rural living, or contact with animals. A TH2-dominated phenotype is associated with high antibiotic use, western lifestyle, urban environment, diet, and sensitivity to dust mites and cockroaches. TH1 and TH2 responses are reciprocally inhibitory, so when one is active, the other is suppressed.
The mechanism of action of the hygiene hypothesis was insufficient stimulation of the TH1 arm, stimulating the cell defence of the immune system and leading to an overactive mother TH2 arm, stimulating the antibody-mediated immunity of the immune systems, which in turn led to allergic disease.
This article has an unclear citation style. The references used may be made clearer with a different or consistent style of , , or . (April 2015)
This explanation however, cannot explain the rise in incidence (similar to the rise of allergic diseases) of several TH1-mediated , including ,
and . [Figure 1Bach] However, the North South Gradient seen in the prevalence of Multiple Sclerosis has been found to be inversely related to the global distribution of parasitic infection.[Figure 2Bach] Additionally, research has shown that MS patients infected with parasites displayed TH2 type immune responses as opposed to the proinflammatory TH1 immune phenotype seen in non-infected multiple sclerosis patients.[Fleming] Parasite infection has also been shown to improve Inflammatory Bowel Disease and may act in a similar fashion as it does in multiple sclerosis.[Lee]
An alternative explanation is that the developing immune system must receive stimuli (from infectious agents, symbiotic bacteria, or parasites) to adequately develop . Without that stimuli it becomes more susceptible to autoimmune diseases and allergic diseases, because of insufficiently repressed TH1 and TH2 responses, respectively. For example, all chronic inflammatory disorders show evidence of failed immunoregulation. Secondly, helminths, non-pathogenic ambient pseudocommensal bacteria or certain gut
and , drive immunoregulation. They block or treat models of all chronic inflammatory conditions. Thirdly, some such organisms (or molecules that they secrete), specifically expand populations of regulatory T cells (Treg), or cause
to switch to regulatory forms that preferentially drive immunoregulation. Finally, when multiple sclerosis patients become infected with helminths, the disease stops progressing and circulating myelin-recognising regulatory T cells appear in the . This indicates that helminths act as
for . This observation led to .
The hygiene hypothesis is supported by epidemiological data. Studies have shown that various immunological and autoimmune diseases are much less common in the developing world than the industrialized world and that immigrants to the industrialized world from the developing world increasingly develop immunological disorders in relation to the length of time since arrival in the industrialized world. This is true for asthma and other chronic inflammatory disorders.
chronic helminthic infection in the endemic region of Russia was found to be associated with lower total
levels and a significant attenuation of
in humans.
Mouse studies have shown that exposure of young mice to viruses can result in a decreased incidence of . However timing is crucial, and ,
virus that can be protective when given very early and can provoke autoimmunity when given late (for instance at weaning).[] Rook also reviewed this issue.
In developed countries where childhood diseases were eliminated, the asthma rate for youth is approximately 10%. In the 19th century, hay-fever, an easily recognisable allergy, was a very rare condition.
Longitudinal studies in Ghana demonstrate an increase in immunological disorders as it grew more affluent and presumably cleaner. These results have been replicated by Weinberg et al. who amassed data from a variety of African countries comparing urban and rural environments as well as high and low socioeconomic status (SES). In all four countries urban and high SES groups had a higher prevalence of exercise induced bronchospasm. The use of antibiotics in the first year of life has been linked to asthma and other allergic diseases. The use of antibacterial cleaning products has also been associated with higher incidence of . Increased asthma rates are associated with birth by . The data supporting links to antibiotic use and caesarean section (but not to antibacterial use) are rapidly strengthening.
Antibiotic usage, which reduces the diversity of gut microbiota, is another cited factor. Although several studies have shown associations between antibiotic use and later development of asthma or allergy, other studies suggest that the effect is due to more frequent antibiotic use in asthmatic children. Trends in vaccine use may also be relevant, but epidemiological studies provide no consistent support for a detrimental effect of vaccination/immunisation on
rates. In support of the old friends hypothesis, the intestinal microbiome was found to differ between allergic and non-allergic Estonian and Swedish children but this finding was not replicated in a larger cohort and the biodiversity of the intestinal flora in patients with Crohn’s disease was diminished.
In 2015, a study found that washing dishes by hand as opposed to using a dishwasher, along with eating food directly from a farm or fermented food, might lead to reduced risk of certain conditions, including asthma, eczema, and possibly hay fever, though the data found on hay fever was not regarded as . It was stated, however, that more research was needed to determine if there was an
between these practices and a reduced risk of allergies and asthma.
King et al. 2004 showed that when short lived
were replaced during a state of too few long lived T-cells (), because of lack of infections, the risk of developing autoimmune diseases increases. They showed that in a state of too few long lived T-cells, because of lack of infections, not enough short lived T cells could be produced by long lived T cells during homeostatic expansion. Therefore, more auto reactive T cells divide in such a state, causing multiplying auto reactive T cells with a greater risk of causing autoimmune diseases like
Cooke showed that
(which spontaneously develop type 1 diabetes) had significantly reduced incidence of this disease when infected with the
parasite .[] Other animal models, also showing that helminth infections block or treat various chronic inflammatory disorders, were comprehensively reviewed recently.
In November 2009 Richard Gallo showed that
helped reduce inflammation.
Early life exposure to specific microbe-enriched environments decreases susceptibility to diseases such as inflammatory bowel disease and asthma, whereas its absence, as in antibiotic treatment during childhood, may have the opposite effect.[] Olszak and colleagues, compared
mice, challenged with aerosol ovoalbumin to promote allergen-induced airway inflammation. They found that early exposure to conventional microbiota protected animals from developing asthma.
Since allergies and other chronic inflammatory diseases are largely diseases of the last 100 years or so, the "hygiene" revolution of the last 200 years came under scrutiny as a possible cause. During the 1800s radical improvements to sanitation and water quality occurred in Europe and North America. The introduction of toilets and sewer systems and the cleanup of city streets, and cleaner food were part of this program. This in turn led to a rapid decline in infectious diseases, particularly during the period , through reduced exposure to infectious agents.
Public health activities have also played a part in affecting diet and lifestyle, such as physical activity levels and locations.
It has been suggested that public awareness of the initial form of the "hygiene hypothesis" has led to an "increased disregard" for hygiene in the home.
While no hygiene-related treatments are part of the standard of care, various approaches are under investigation. Helminth therapy is one alternative.
(drinks or foods) have never been shown to reintroduce microbes to the gut. As yet, therapeutically relevant microbes have not been specifically identified.
Lifestyle changes could increase microbial exposure, but whether this on balance improves the balance of risks remains the subject of research. Proposals include natural childbirth, sustained breast feeding and physical interaction between siblings, and encouraging children to spend more time in "uncleaned" outdoor environments.
Should these therapies become accepted, public policy implications include providing green spaces in urban areas or even providing access to agricultural environments for children.
Main article:
Helminthic therapy is the treatment of
by means of deliberate infestation with a
or . Helminthic therapy is currently being studied as a promising treatment for several (non-viral)
including , multiple sclerosis, asthma, and . Autoimmune liver disease can be modulated by active helminth infections.
The anti-inflammatory effects of helminth infection are prompting interest and research into diseases that involve inflammation but that are not currently considered to include autoimmunity or immune dysregulation as a causative factor. Heart disease and arteriosclerosis both have similar epidemiological profiles as autoimmune diseases and both involve inflammation. Their increased incidence cannot be solely attributed to environmental factors. Recent research explored the eradication of helminths as contributing to this discrepancy.
Helminthic therapy emerged from the search for reasons why the incidence of immunological disorders and autoimmune diseases correlates with the level of industrial development.
Related therapies include use other types of infectious organisms, such as protozoa.
No evidence supports the idea that reducing modern practices of cleanliness and hygiene would have any impact on rates of chronic inflammatory and allergic disorders, but a significant amount of evidence that it would increase the risks of infectious diseases.
If home and personal cleanliness contributes to reduced exposure to vital microbes, its role is likely to be small. The idea that homes can be made “sterile” through excessive cleanliness is implausible. The evidence shows that, as fast as they are removed by cleaning, microbes are replaced, via dust and air from outdoors, by shedding from the body and other living things as well as from food. The key point may be that the microbial content of urban housing has altered, not because of home and personal hygiene habits, but because they are part of urban environments. Diet and lifestyle changes also affects the gut, skin and respiratory microbiota.
At the same time that concerns about allergies and other chronic inflammatory diseases have been increasing, so also have concerns about infectious disease. Infectious diseases continue to exert a heavy health toll. Preventing
and reducing
are global priorities. Hygiene is a cornerstone of containing these threats.
The International Scientific Forum on Home Hygiene has developed a risk management approach to reducing home infection risks. This approach uses microbiological and epidemiological evidence to identify the key routes of infection transmission in the home. These data indicate that the critical routes involve the hands, hand and food contact surfaces and cleaning utensils. Clothing and household linens involve somewhat lower risks. Surfaces that contact the body, such as baths and hand basins, can act as infection vehicles, as can surfaces associated with toilets. Airborne transmission can be important for some pathogens. A key aspect of this approach is that it maximises protection against pathogens and infection, but is more relaxed about visible cleanliness in order to sustain normal exposure to other human, animal and environmental microbes.
There are other hypotheses that try to explain the increase in
in developed nations. Major areas of focus include infant feeding, over-exposure and exposure to certain pollutants.[]
Infant feeding topics includes breastfeeding, when babies begin to eat solid foods and the type of these foods, cow's milk vs other milks and variations in milk processing.
Over-exposure to allergens in occupational situations can cause allergic responses, such as , ,
and bakers lung (See ).
Another theory suggests that pollution (such as )
however, improvements in air quality since the 1970s do not self-evidently support such claims.[] The
was proposed by Albert Bernard and his colleagues as an alternative hypothesis based on
evidence in 2003.
(includes more discussion of hygiene hypothesis)
William Parker (). . The Evolution & Medicine Review.
Strachan, D. (2000). "Family size, infection and atopy: The first decade of the 'hygiene hypothesis'". Thorax 55 (90001): 2S. :.
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Stanwell-Smith R, Bloomfield SF, Rook GA. The hygiene hypothesis and its implications for home hygiene, lifestyle and public health. International Scientific Forum on Home Hygiene.
Bloomfield SF, Stanwell-Smith R, Rook GA. The hygiene hypothesis and its implications for home hygiene, lifestyle and public health: summary. International Scientific Forum on Home Hygiene.
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