Many normal flora organisms are not pathogenic as long as the host is in good health. However if host resistance mechanisms fail - either through some other infection process or through immunodeficiency, these normal flora organisms become pathogenic.
Can normal microbial flora become pathogenic?
Yes, normal microbial flora can become virulent or pathogenic if the conditions are right. On outside of body normal flora is harmless, if it was to be ingested it would take the opportunity to do as much damage as possible. What terminology is not used for resident flora?
Can normal flora cause a disease?
Normal flora cannot cause a "disease". But if normal flora is disrupted it can become a pathogen and then cause infection. Some diseases, like diabetes, can disrupt normal flora and cause infection, especially yeast infections on the skin or in the vagina of women.
Why do I keep getting infections from my own flora?
In most circumstances it happens either because your immune system is compromised or because the said flora ends up in a place where it should not be. Toxoplasmosis for exemple, while not technically part of your ‘’normal’’ flora, is an opportunistic pathogen.
What is the difference between normal flora and transient bacteria?
there are many types but the general term used is that those bacteria are your normal flora but these bacteria though they are non pathogenic to you can be to someone else Differentiate between normal flora and transient bacteria found on skin? Normal flora is permanent to our skin, while Transient flora is temporary to our skin
Can normal bacteria become pathogenic?
Bacteria belonging to the microbiota, and therefore considered as commensals, can also become pathogenic if their growth rate raises and if they outcompete other members of the intestinal flora. For bona fide pathogens, variability in the expression of virulence factors has also been observed.
What factors can interfere with the normal flora to cause an infection?
A variety of factors can disrupt the normal flora including age, diet, stress, illness and exposure to antibiotics.
What can affect normal flora?
The normal flora of humans are exceedingly complex and consist of more than 200 species of bacteria. The makeup of the normal flora may be influenced by various factors, including genetics, age, sex, stress, nutrition and diet of the individual.
What is the most common cause of pathogenic bacteria?
Most Common Foodborne PathogensSalmonella.Sources: You can contract salmonellosis by consuming raw and undercooked eggs, undercooked poultry and meat, contaminated raw fruits and vegetables (such as sprouts and melons), as well as raw milk and other dairy products that are made with unpasteurized milk.More items...•
What happens when normal flora is disrupted?
Another way a microbe can cause endogenous infection is if the immune system is impaired or the normal flora is disrupted. Disruption of the normal flora, as mentioned above, can lead to infections with Candida or C. difficile.
What bacterial organism of normal skin flora is potentially pathogenic?
Staphylococcus epidermidis is highly adapted to the diverse environments of its human host. S. aureus is a potential pathogen. It is a leading cause of bacterial disease in humans.
How are normal flora destroyed?
Antibiotic resistance represents a pressing problem, normal flora is destroyed by unnecessary use of antibiotics and as a result, microorganisms with resistance genes multiply.
Can natural flora ever be harmful to our bodies?
Disease-causing microorganisms are called pathogens. Even though most of the time they are harmless or even helpful, in certain conditions some of the bacteria that are part of the human microbiota can harm us. For example, bacteria that live on the skin can become a problem.
How antibiotics influence the normal flora in the body?
Antibiotics that are prescribed to treat pathogenic bacteria also have an impact on the normal microbial flora of the human gut. Antibiotics can alter the composition of microbial populations (potentially leading to other illnesses) and allow micro-organisms that are naturally resistant to the antibiotic to flourish.
What are the two primary sources of pathogenic bacteria?
Some of the established bacterial contamination sources include contaminated manure, irrigation water, soil, livestock/ wildlife, and numerous factors influence the incidence, fate, transport, survival and proliferation of pathogens in the wide variety of sources where they are found.
Where do pathogenic bacteria come from?
Particularly untreated fruits, vegetables, raw meat products, raw milk products as well as water are often sources for possible bacterial infections.
How do you know if bacteria is pathogenic?
Such pathogens are usually diagnosed by the detection of specific antibodies in conjunction with the assessment of clinical symptoms or the molecular detection of specific DNA sequences.
What is normal flora?
Normal flora are friendly microbes of our body. They protects Hunan body from various pathogens. For instance, microbes residing in our gut like E. Coli produces vitamins. Also, there are huge number of normal flora present on the surface of our skin which helps to prevent the attachment of foreign microbes.
What happens to bacteria when they become unbalanced?
in our body works WITH the body. If it becomes unbalanced and conditions are not good they can go off in different directions, form colonies, etc. and become pathogenic. There is a lot of talk about this with respect to anti-biotic, which alter the balance.
How long does a fungus stay in your body?
It can stay mostly latent in your body, for years, until your immune system is compromised and then it becomes pathogenic. For the most part you normal/friendly flora wont become pathogenic unless they end up in a place where they should not be.
Why does my colon grow in another part of my body?
your colon where it’s normal flora, begins to grow in another sterile part of your body, e.g. bladder (urine), blood, etc. due to mechanical issues such as surgery (wounds), sex, foreign objects (central line catheters) or your immune system is compromised due ...
Do bacteria live on the skin?
Next to the gut, large numbers of bacteria live on our skin, gum and to a less extent in the genitalia. There are some bacterial pathogens in the gut, skin, gingival tissues and genitalia which cause diseases. That is how you know that they exist. In general, viruses and fungi are not beneficial to humans.
Does microflora need food?
Microflora needs food and generate waste. Our friendly flora is no exception but when in their normal habitat this is no problem. Things balances out, they feed from our waste and their waste is eliminated and their population is at an equilibrium. Our immune system is used to this and we stay healthy, in balance.
Is yeast a pathogen?
Even yeast, which exists normally certainly can be pathogenic if the balance goes out of wack.
Biofilms as reservoirs for disease
See Flanders and Yildiz Chap 17 In Microbial Biofilms by Ghannoum and O’Toole
An example: Human Oral Microbes and Dental caries
a. Mechanism of pathogenicity b. Microbial succession c. Coaggregation Paul Kolenbrander d. Keystone species – Fusobacterium nucleatum e. Prevention
How are bacterial pathogens transmitted?
Many bacterial pathogens are transmitted to the host by a vector, usually an arthropod. For example, Rocky Mountain spotted fever and Lyme disease are both vectored by ticks, and bubonic plague is spread by fleas. Susceptibility to these diseases depends partly on the host's contact with the vector.
What are the factors that help bacteria invade the host?
Most pathogenic bacteria multiply in tissue fluids and not in host cells. Virulence Factors. Virulence factors help bacteria to (1) invade the host, (2) cause disease, and (3) evade host defenses. The following are types of virulence factors:
How do bacteria acquire virulence factors?
Other virulence factors are acquired by bacteria following infection by a particular bacteriophage, which integrates its genome into the bacterial chromosome by the process of lysogeny (Fig. 7-2). Temperate bacteriophages often serve as the basis of toxin production in pathogenic bacteria.
What is the signaling mechanism that phagocytic cells use to recognize foreign cells?
Bacteria invading tissues encounter phagocytic cells that recognize them as foreign, and through a complex signaling mechanism involving interleukins, eicosanoids, and complement, mediate an inflammatory response in which many lymphoid cells participate.
What is the objective of bacteria infectivity?
The “objective” of bacteria is to multiply rather than to cause disease; it is in the best interest of the bacteria not to kill the host. Host Resistance.
What is the term for the invasion of the host by microorganisms?
Infection is the invasion of the host by microorganisms, which then multiply in close association with the host's tissues. Infection is distinguished from disease, a morbid process that does not necessarily involve infection (diabetes, for example, is a disease with no known causative agent).
Why is it not in the best interest of the pathogen to kill the host?
From a teleologic standpoint, it is not in the best interest of the pathogen to kill the host, because in most cases the death of the host means the death of the pathogen.
