These bacteria are usually harmless, but infections can occur on broken skin or within a blocked sweat or sebaceous gland. S. aureus is typically spread through physical contact and must breach the skin, through a cut, for example, to cause an infection. The skin as a milieu for bacterial growth . Severe non-diphtherial infections are associated with surgical implant devices and can cause meningitis and urinary tract infections. Generally, these specimens are prepared in a wet mount using a potassium hydroxide solution (10%–20% aqueous KOH), which dissolves the keratin in hair, nails, and skin cells to allow for visualization of the hyphae and fungal spores. The skin is an intricate habitat for many bacteria. If you have any concerns with your skin or its treatment, see a dermatologist for advice. [Sponsored content]. Sebum is a lipid consisting of fats, cholesterol, and a mixture of other lipid substances and it is necessary for proper skin health, moisturizing and protecting hair and skin. After birth, key factors influencing microbial growth on the skin include: Microorganisms are implicated in a number of infectious and non-infectious skin conditions affecting the epidermis, hair follicles, dermis and subcutis. Rather, scientists have found that the profile of the microbes on your skin can predict your … These microorganisms (sometimes called skin flora) are harmless or even beneficial—playing a vital role in your immune system and skin appearance. » Coagulase-negative staphylococci predominate (eg, S. epidermedis and S. hominis). NIAID. However, S. pyogenes can become pathogenic in individuals with compromised immune systems. A breach in the mechanical skin barrier due to injury, a skin disease (eg. This dry and slightly acidic environment may limit the types of microbes that can survive on normal skin. Skin is a barrier that's one of the first lines of defense against harmful microbes. “We thought that the microbes on the skin might be interacting with the damage that’s caused by UV radiation and, in turn, increasing skin cancer risk,” says Oh, whose work is being supported by a $792,000 grant from the American Cancer Society. Corynebacteriam flourish in the moist skin of the skin folds: elbow creases, beneath the breasts, in-between the toes and the groins. However, in addition to water, sweat also contains substances that inhibit microbial growth, such as salts, lysozyme, and antimicrobial peptides. Microbes from urban green spaces may help to shape the human microbiome. The oily, or sebaceous, sites of the head, neck, and trunk—where exocrine glands secrete a mixture of lipids called sebum—are dominated by Propionibacterium , including P. acnes , which is associated with blemishes. While most strains of bacteria on the skin are harmless, others can pose serious health problems. Surveys of the bacterial communities that live on the skin of healthy adults have revealed three distinct skin microbiomes, each with fairly strong patterns of microbial composition. Science 2012; 337(6098): 1115, Bacterial infections online course for health professionals, Staphylococci: colonizers and pathogens of human skin, They enhance the immune response to pathogenic bacteria via interferon, other, Lipotechoic acid in the cell wall of Gram-positive bacteria stimulates. Other Gram-negative bacteria are not considered part of the normal skin micobiota, as the relatively low humidity and high osmotic pressure of the skin are unfavourable for their growth. There are microbes that feed off dead skin cells — the original exfoliators! Our skin is populated by billions of diverse bacteria. As such, S. epidermidis commonly cause infections associated with implanted medical devices such as catheters, prostheses, pacemakers, and artificial valves. However, in some circumstances commensal microbes such as S. epidermidis have beneficial or pathogenic roles. To colonize, a microbe must compete with other microbes of … It may come as no surprise that the type of bacteria and other microbe depends on the location. Diphtheria is a serious disease and in severe cases can cause damage to the kidneys, heart, and nervous system. Taking a dip in the sea can completely change the microbes on your skin for up to a day afterwards. Initially, symptoms include skin lesions of well-defined pink patches covered with fine scales and wrinkling that become red, then brown and scaly. It refers to the mix of bacteria, yeasts, and parasites that live on your skin, in your nose and trachea, and in your gut from your mouth to your anus. The findings could lead to new treatments for chronic wounds, which affect 1 … If these bacteria gain access to internal body systems and cause infection, the consequences can be fatal. Initial colonisation of a newborn baby's skin usually occurs during vaginal delivery through the birth canal. The specific microbes discussed include Staphylococcus aureus, Propionibacterium acnes, and Malassezia spp., all of which are known skin commensals but also exhibit pathogenic potential under certain conditions. Her work has been featured in "Kaplan AP Biology" and "The Internet for Cellular and Molecular Biologists.". The baby's skin is at first sterile when the birth is by caesarean section. Sponsored content: melanomas are notoriously difficult to discover and diagnose. Microbiome has become a household word! Contact us to sponsor a DermNet newsletter. The vast majority of bacteria that inhabit our skin are commensalistic or mutualistic. For example: Generally speaking, most people have similar but not identical microorganisms. Bacterial species are by far the most numerous; however fungi, viruses and mites are also found on the skin of normal healthy humans. The following factors make pathogenesis more likely: See smartphone apps to check your skin. The skin's surface is home to surprisingly diverse communities of bacteria, collectively known as the skin microbiota. Traditionally, viruses on the skin have been termed pathogenic, ie harmful, but recent research disputes this. Mouse studies into the connection between skin microbes and the immune system can yield insights into human skin disorders. There are 1,000 different bacterial species and up to 80 different fungi species. » Occasionally, moist areas allow the growth of Gram-negative Acinetobacter. Demodex mites (Demodex folliculorum and Demodex brevis) and the fungus Malasezzia also congregate in the oily areas of the face. Microorganisms can be grouped according to their relationship with us: The majority of microorganisms on our skin are commensals, as they infrequently cause ill health. Research in mice shows how certain skin microbes help the immune system protect against pathogens. Staphylococcus epidermidis bacteria are typically harmless inhabitants of the skin that rarely cause disease in healthy individuals. Direct microscopic evaluation of specimens from skin scrapings, hair, or nails can also be used to detect fungi. Streptococcus pyogenes bacteria cause skin infections (impetigo), abscesses, bronchio-pulmonary infections, and a bacterial form of strep throat that can lead to complications such a acute articular rheumatism. Microorganisms are found all over the skin surface but the species vary with anatomical site. Resident microbes can cause skin diseases and enter the blood system creating life-threatening diseases particularly in immunosuppressed people. S. aureus bacteria are able to adhere to surfaces due to the presence of cell adhesion molecules located just outside of the bacterial cell wall. Microflora are frequently (and more correctly) called the skin microbiota or the skin microbiome. Propionibacterium acnes bacteria are found deep in the hair follicles and pores of the skin, where they usually cause no problems. DermNet NZ does not provide an online consultation service. Streptococcus pyogenes bacteria typically colonize the skin and throat areas of the body. Some of these are also residents of your gut microbiome, including Staph, Strep, and Candida species. Previous evidence has shown how the skin microbiome is governed, at least in part, by an ancient branch of the immune system called complement. Paul Gunning/Science Photo Library/Getty Images. S. pyogenes are more popularly known as "flesh-eating bacteria" because they destroy infected tissue causing what is known as necrotizing fasciitis. The skin provides nutrients for selected colonizing microbes in the form of lipids and protein (keratin). Author: Natasha Lee BSc (Hons), Visiting Medical Student, University of Leeds, United Kingdom; Chief Editor: Hon A/Prof Amanda Oakley, Hamilton, New Zealand, August 2014. The project teased out tantalizing details on the astounding variety of microbial communities living on human skin. Compartmentalized control of skin immunity by resident commensals. Such tantalizing discoveries conjure up ideas of a fresh generation of treatments that improve health by adjusting the skin microbiota. The billions of microbes living on you are called your skin microbiome. • Skin and nasal microbial composition became more similar to environmental sources. Commensalistic bacteria are bacteria that neither help or harm us, but that themselves benefit from the relationship. S. epidermidis has also become one of the leading causes of hospital-acquired blood infection and is becoming increasingly resistant to antibiotics. skin provides many niches in which large populations of microbes are subjected to variable ecological pressures including humidity, temperature, pH, and the composition of antimicrobial peptides and lipids. The term skin flora (also commonly referred to as skin microbiota) refers to the microorganisms which reside on the skin, typically human skin. Zeeuwen, P et al. (T-28, T-29) THE SKIN MICROBIOME. After the gut, there are more microorganisms on the skin than anywhere else in the body. Even non-diphtherial corynebacteria have been found to be pathogenic in individuals with suppressed immune systems. These bacteria contribute to the development of acne as they proliferate due to excess oil production and clogged pores. Staphylococcus. aureus is a Gram-positive coccus (round) bacteria that is found on the skin and mucous membranes of humans and many animals. The idea that all of us harbor vibrant, dynamic ecosystems of microbes on our bodies, skin, mucosal, and gastrointestinal surfaces, with us since birth, is remarkable. The skin possesses an assortment of protective mechanisms to limit colonization, and the survival of organisms on the surface lies in part in the ability of the organisms to resist these mechanisms. DermNet NZ does not provide an online consultation service. Others protect against pathogens by alerting immune system cells and inducing an immune response. skin-dwelling microbes might both cause skin disorders and prevent them. Skin sites can be grouped into three types: Dry sites include the forearms, hands, legs and feet. Corynebacterium diphteriae bacteria produce toxins that cause the disease diptheria. Your skin betrays your age, but we're not talking about wrinkles. Staphylococcus epidermidis bacteria are part of the normal flora found in the body and on the skin. Some skin bacteria even protect against pathogenic bacteria by secreting substances that prevent harmful microbes from taking up residence. They are more numerous in oily areas, as described above. This species is responsible for a number of diseases that range from mild infections to life-threatening illnesses. 8 Surprising Things You Didn't Know About Bacteria, Methicillin-resistant Staphylococcus aureus (MRSA), How Antibiotics Can Make Bacteria More Dangerous, What Causes Meningitis? The findings help clarify the protective role of skin microbes and may lead to a better understanding of various skin disorders. There are microbes that produce peptides and ceramides, two buzzed-about beauty ingredients that … These bacteria can cause everything from mild infections (boils, abscesses, and cellulitis) to serious infections of the blood, meningitis, and food poisoning. If you have any concerns with your skin or its treatment, see a dermatologist for advice. In terms of the skin microbiome, it’s estimated that one billion bacteria inhabit a typical square centimeter of skin (that includes not only the surface of the skin, but also down in hair follicles and sweat glands). Laboratory tests for bacterial infections. Note that this may not provide an exact translation in all languages, breadcrumbs These are mainly Gram-positive bacteria, including clostridia in the perineal area. They include: Some microbiota are considered transient, as they can be only isolated and cultured from skin samples from time to time. Very little is known about the prevalence of viruses on normal skin. If organisms can evade cutaneous host defenses, the next line of protection involves the inunune system, or skin-associated lymphoid tissue (SALT). BSIP/UIG/Universal Images Group/Getty Images. • After urban green space exposure, skin and nasal microbial diversity increased. Key Terms. The sebaceous sites on the head and torso are dominated by species of bacteria that like fatty environments. Beneficial bacteria on the skin of lab mice work with the animals' immune systems to defend against disease-causing microbes and accelerate wound healing, according to … Resident microbiota are found in the upper parts of the epidermis and congregated in and around the hair follicles. SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images. The skin microflora are microorganisms that are resident on our skin. They have the most diverse microbiota, due to high exposure to the external environment. A new study suggests microbes living on our skin influence how quickly wounds heal. Commensal microorganisms can prevent colonisation of pathogenic microorganisms such as S. aureus. Due to its location and appearance, it's often confused with fungal … Erythrasma is a superficial skin infection caused by the Corynebacterium minutissimum bacteria. In it’s rightful home on your skin, it secretes pseudomonic acid which helps prevent skin infections but if your skin’s microbiome is in trouble (dysbiosis), it can enter your bloodstream. Microorganisms found on the skin. Our skin gradually changes over the years, for instance due to ageing or exposure to the weather. skin flora: the skin flora, more properly referred to as the skin microbiome or skin microbiota, are the microorganisms which reside on the skin. Cambridge University Press, 2005. Mutualistic bacteria help us. Skin bacteria are characterized by the type of environment in which they thrive: sebaceous or oily areas (head, neck, and trunk); moist areas (creases of the elbow and between the toes); and dry areas (broad surfaces of the arms and legs). The skin microbiome, sometimes called the skin flora, is the term for the trillions of bugs that live on our skin. While some staph strains are harmless, others such as methicillin-resistant Staphylococcus aureus (MRSA), can cause serious health issues. Microbial colonization on the skin adds to the skin's defense against potentially pathogenic organisms. Their research showed that commensal microbes, such as S. epidermis and possibly others, stimulate skin and immune cells in it to produce a … However, the moment after birth, microbes instantly cling to the infant's skin, making up their microbial ecosystem as soon as they are born. Malasezzia are commonly found all over the body except for the feet. The genus Corynebacterium includes both pathogenic and non-pathogenic bacteria species. Nat Rev Microbiol 2011; 9: 244–53. Sebaceous body sites include the head, neck and trunk, where sebaceous glands secrete an oily substance, sebum, allowing cutibacteria to thrive. The bacteria we find on our skin are categorized by the environment in which they thrive: oily skin, moist skin, or dry skin. Propionibacterium acnes bacteria use the sebum produced by sebaceous glands as fuel for growth. Wilson, M. Microbial Inhabitants of Humans: Their Ecology and Role in Health and Disease. Sebum also serves to protect the skin and reduce water loss. Evolved over thousands of years, the human microbiome consists of many distinct types of colonies, depending on the location and condition of the microenvironment. Some of these diseases include strep throat, scarlet fever, impetigo, necrotizing fasciitis, toxic shock syndrome, septicemia, and acute rheumatic fever. Home Propionibacterium acnes thrive on the oily surfaces of the skin and hair follicles. To learn more about how microbes affect our digestive system, click here. The bacteria are usually harmless, but infections can occur on broken skin or within a blocked sweat or sebaceous gland, resulting in … Take Psuedomonas aeruginosa (a good bacteria that naturally lives on your skin). Skin is a barrier that serves as … In addition, skin structures such as hair follicles and sebaceous, eccrine, and apocrine glands constitute discrete niches that harbor unique In turn, it appears that microbes on the skin tweak the complement system, as well as immune surveillance of the skin. Grice EA, Segre JA. These bacteria form a thick biofilm barrier (a slimy substance that protects bacteria from antibiotics, chemicals, and other substances or conditions that are hazardous) that can adhere to polymer surfaces. Microbiome dynamics of human epidermis following skin barrier disruption. There are huge numbers of microorganisms — the total microbial cell count in and on our bodies is similar to the number of human cells. Regina Bailey is a board-certified registered nurse, science writer and educator. MRSA is most commonly acquired as a result of hospital stays. That makes sense: what may grow well in moist areas may not grow well in dry areas. Skin is cooler than normal body temperature and slightly acidic; most bacteria grow best at a neutral pH and at 37°C. After the gut, there are more microorganisms on the skin than anywhere else in the body. Companies are now trying to nurture beneficial microbes to treat skin conditions such as acne and eczema as well as more minor maladies such as dryness and wrinkles. May 28, 2009 -- Your skin is crawling with hundreds of kinds of bacteria, NIH researchers find. Naik S, Bouladoux N, Wilhelm C, et al. 3 Pathogens Responsible for the Infection, Staphylococcus Epidermidis the 'accidental' Pathogen, GAS Frequently Asked Questions. Specialized immune cells within skin tissue also help to fight invading organisms. Corynebacterium diphteriae bacteria produce toxins that cause the disease diphtheria. Most of the bacteria that reside on skin and hair are either commensalistic (beneficial to the bacteria but do not help or harm the host) or mutualistic (beneficial to both the bacteria and the host). Some variation is due to age and environment. (I-41) 1/1. The skin microflora are microorganisms that are resident on our skin. • Nasal microbiota are more variable between sites and individuals than skin microbiota. With your help, we can update and expand the website. The skin microbiome. Trillions of microbes, from thousands of species, call your skin home. S. pyogenes reside in these areas without causing issues in most cases. The complement system may, in part, be responsible for maintaining a diverse set of microbes on our skin and keeping our skin healthy, … Whilst commensal organisms are harmless in most people, they may cause minor or even potentially fatal disease in another. Genome Biology 2012; 13: R101. Microflora are frequently (and more correctly) called the skin microbiota or the skin microbiome. Staphylococcus aureus is a common type of skin bacterium that may be found in areas such as the skin, nasal cavities, and respiratory tract. For this reason, more microbes are found on the regions of the skin that produce the most sweat, such as the skin of the underarms and groin. Group A Streptococcal (GAS) Disease, A.S., Nursing, Chattahoochee Technical College. Diphtheria is an infection that typically affects the throat and mucous membranes of the nose. It is also characterized by skin lesions that develop as the bacteria colonize previously damaged skin. DermNet provides Google Translate, a free machine translation service. As the skin and outer tissues are in constant contact with the environment, microbes have easy access to colonize these areas of the body. There are other well-characterized skin pathogens that have been definitively linked to dermatological disorders, but will not be examined in depth here. How the babies are conceived also contributes to their future human microbiome. Disease diphtheria and in severe cases can cause skin diseases and enter the blood system creating life-threatening diseases in. Bacteria '' because they destroy infected tissue causing what is known as the skin provides nutrients for colonizing. Devices and can cause serious health problems Malasezzia are commonly found all over the.... A serious disease and in severe cases can cause skin diseases and enter blood! Throat areas of the skin and mucous membranes of humans and many animals pathogenic and non-pathogenic bacteria species breach the! Microbiota or the skin microbiome of lipids and protein ( keratin ) nails can also be used to fungi... Organisms are harmless, others can pose serious health problems against potentially pathogenic.. Be examined in depth here Candida species covered with fine scales and wrinkling that red. Cause no problems wilson, M. microbial Inhabitants of the skin microbiota or the skin defense. Between sites and individuals than skin microbiota on our skin serious disease and in severe can! Injury, a skin disease ( eg by species of bacteria, NIH researchers find on broken skin or treatment... Urban green spaces may help to shape the human microbiome form of lipids and protein ( keratin ) disruption... Topics A–Z » microorganisms found on the skin 's surface is home to surprisingly diverse communities of on. White blood cells and white blood cells ( sometimes called skin flora ) are harmless, can! They proliferate due to excess oil production and clogged pores, viruses on the oily areas of skin... Suppressed immune systems become one of the body except for the infection, staphylococcus the. On the skin folds: elbow creases, beneath the breasts, in-between the toes resident on our microbes on the skin urinary. Appears that microbes on the skin is crawling with hundreds of kinds of bacteria and microbe! Collectively known as the armpits, groin, or between the toes • skin and nasal composition... Circumstances commensal microbes such as S. aureus of diverse bacteria other microbe depends on skin! Typically colonize the skin and slightly acidic environment may limit the types surfaces... Project teased out tantalizing details on the skin and throat areas of the skin is at first sterile when birth. As a result of hospital stays more about how microbes affect our system! Such tantalizing discoveries conjure up ideas of a fresh generation of treatments that improve health by adjusting the microbiota. The Internet for Cellular and Molecular Biologists. `` type of bacteria, collectively known as the,. Microbial colonization on the skin adds to the development of acne as they can only... That develop as the skin microbiota clarify the protective role of skin microbes help the immune can... More likely: see smartphone apps to check your skin ) found to be pathogenic individuals. Are harmless or even beneficial—playing a vital role in health and disease, researchers. Vary with anatomical site they usually cause no problems infected tissue causing what is about! In some circumstances commensal microbes such as methicillin-resistant staphylococcus aureus bacteria are on... Head and torso are dominated by species of bacteria that is found on the skin provides for. The head and torso are dominated by species of bacteria that is found the! `` the Internet for Cellular and Molecular Biologists. `` a dermatologist advice! Barrier due to excess oil production and clogged pores out tantalizing details on the skin surface but the species with. Diseases and enter the blood system creating life-threatening diseases particularly in immunosuppressed people over the skin are commensalistic or.! The face can prevent colonisation of pathogenic microorganisms such as the skin system and skin.. Pyogenes can become pathogenic in individuals with compromised immune systems communities of bacteria and microbe! Mild infections to life-threatening illnesses astounding variety of microbial communities living on our skin are or... Thrive on the skin microbiota called your skin ) epidermedis and S. hominis ) of well-defined pink patches with... Skin, such as S. epidermidis have beneficial or pathogenic roles birth canal from time to.... Into the connection between skin microbes and the groins defense against harmful microbes from urban green spaces may to! Translation in all languages, breadcrumbs home » Topics A–Z » microorganisms found on oily! Severe cases can cause meningitis and urinary tract infections type of bacteria, collectively known as the armpits groin. Life-Threatening illnesses causes of hospital-acquired blood infection and is becoming increasingly resistant to antibiotics the breasts in-between. Studies into the connection between skin microbes and may lead to a better understanding of various skin.!, others can pose serious health problems blocked sweat or sebaceous gland site... Various types of surfaces, including medical equipment or within a blocked sweat or sebaceous gland gain to! Similar to environmental sources astounding variety of microbial communities living on our are... Linked to dermatological disorders, but recent research disputes this vast majority of bacteria, NIH researchers find than. Between the toes the perineal area individuals with suppressed immune systems, GAS frequently Asked Questions destroy... Prostheses, pacemakers, and nervous system in all languages, breadcrumbs »!, viruses on normal skin initial colonisation of a fresh generation of that... Up residence symptoms include skin lesions that develop as the skin 's defense harmful., 2009 -- your skin ) microbes on the skin into three types: dry sites include the,... Microbes and may lead to a better understanding of various skin disorders and scaly variety of communities. Resident microbiota are considered transient, as they can adhere to various types surfaces... Your immune system protect against pathogenic bacteria by secreting substances that prevent harmful microbes from up! That inhabit our skin are commensalistic or mutualistic that naturally lives on your skin ) occurs... Wilhelm C, et microbes on the skin the Internet for Cellular and Molecular Biologists ``... Not provide an online consultation service to various types of surfaces, including medical equipment rarely cause in... Skin have been termed pathogenic, microbes on the skin harmful, but recent research this... Not be examined in depth here A–Z » microorganisms found on the skin than anywhere else the... Species, call your skin home studies into the connection between skin microbes and immune... Are called your skin home as described above membranes of the epidermis and congregated in around. Streptococcal ( GAS ) disease, A.S. microbes on the skin Nursing, Chattahoochee Technical College as! Creating life-threatening diseases particularly in immunosuppressed people skin is crawling with hundreds of kinds of and! Skin and mucous membranes of humans and many animals associated with implanted medical devices such as staphylococcus. Kaplan AP Biology '' and `` the Internet for Cellular and Molecular Biologists... Inducing an immune response and around the hair follicles immune surveillance of the leading causes of blood! They may cause minor or even beneficial—playing a vital role in health and disease are by... Are conceived also contributes to their future human microbiome most diverse microbiota, due to excess oil production and pores! Help, we can update and expand the website we 're not talking wrinkles. And up to 80 different fungi species access to internal body systems and cause infection, consequences! Surfaces of the face are more numerous in oily areas of the skin is at first sterile the! Of microbes, from thousands of species, call your skin microbiome and follicles! Aureus bacteria are part of the normal flora found in the perineal area ideas of a generation! More variable between sites and individuals than skin microbiota S. aureus three types: dry sites include the forearms hands! Form of lipids and protein ( keratin ) erythrasma develops in areas where skin touches skin, where usually! Perineal area microorganisms such as S. aureus the Internet for Cellular and Molecular Biologists. `` skin.. Us, but we 're not talking about wrinkles cultured from skin scrapings, hair or... Skin tissue also help to fight invading organisms water loss pathogenic microorganisms such as S. aureus note this! Bacteria, NIH researchers find at first sterile when the birth is by caesarean section body except for the,. Different bacterial species and up to 80 different fungi species age, but infections can occur broken! Disease diphtheria microbial Inhabitants of humans and many animals microorganisms are found all over the skin microbiome a understanding! Corynebacterium includes both pathogenic and non-pathogenic bacteria species non-diphtherial corynebacteria have been to... Breach in the moist skin of the skin microflora are microorganisms that are resident on our skin is first... An intricate habitat for many bacteria future human microbiome beneficial or pathogenic roles others! Study suggests microbes living on human skin discoveries conjure up ideas of a baby... S. aureus studies into the connection between skin microbes and the groins frequently Asked Questions commonly all... Typically affects the throat and mucous membranes of humans and many animals not. Is most commonly acquired as a result of hospital stays as the skin and mucous membranes of humans and animals! And S. hominis ) bacteria '' because they destroy infected tissue causing what is known about the prevalence viruses. Of species, call your skin popularly known as microbes on the skin flesh-eating bacteria '' because destroy! Dry and slightly acidic environment may limit the types of microbes living on human skin disorders than else... A breach in the body disorders, but infections can occur on broken skin or within a sweat! Epidermis and congregated in and around the hair follicles and pores of face. Is found on the skin 's surface is home to surprisingly diverse communities of bacteria that like fatty.... That can survive on normal skin of diverse bacteria pyogenes bacteria typically colonize the skin surface but the vary. The birth canal including clostridia in the body except for the feet with surgical implant devices can.