There are some micro-organisms with the capability to cause disease defined as pathogens (1). Now, imagine a weighing-scale representing the pathogen’s interactions with its environment. The left characterizes the virulence factors which are properties of a micro-organism to increase its chances of establishing itself within a host (2), the right signifies the host equipped with a sophisticated immune system. Suddenly, the scale tips to the left, representing a biological war which favours an outcome where the ability to cause disease has won. That is pathogenicity.
The purpose of pathogenicity varies fairly much; in the case of extremely destructive pathogens such as Ebola or Marburg upon infecting humans, host morbidity is virtually
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However, the pathogen can avoid this and in other instances it, must survive further immune responses that vary in intensity.
For example, the complement system, a dominant innate response component is highly important. It marks pathogens for phagocytosis, kills them via pore formation directly and stimulates B-cells (6). It is essentially the bridge transitioning the immune response from innate to adaptive. Pseudomonas aeruginosa express proteases (e.g. Pseudomonas elastase (PaE)) which degrade C1q and C3 (6) and thus avoiding complement activation on the bacterial surface. It increases the virulence of the bacteria. This is by escaping confrontation with further components of the complement system (5). Consequently, the system cannot heighten the abilities of antibodies or promote inflammation.
Another complement evasion strategy is the use of microbial complement inhibitors, a direct intervention. Herpes viruses have transmembrane glycoproteins gC1 and gC2 which bind C3b (7) , accelerating the decay of C3 convertase of the alternative pathway (7). Thus, no complement cascade will occur or opsonisation.
The host-pathogen relationship can characterise host damage in response to a pathogen as a function of time (8).The human immunodeficiency virus (HIV) is highly advantageous in its pathogenicity as it not only
Chapter 11 further explains what we have previously learned in Chapter 10. In Chapter 11 the book discusses immunity and the diseases one may be immune too. For example, if one has measles they are less likely to get it a second time because their body is immune to the disease. The human body has various different mechanisms that help fight off diseases that are infectious such as measles and the other infectious diseases we previously learned about in Chapter 10.
Bloodborne Pathogens are pathogenic microorganisms that can eventually cause disease. They are found in human blood and other bodily fluids such as synovial fluid, semen, vaginal secretions, cerebrospinal fluid and any other fluid that mixes or has contact with blood. The bloodborne pathogens are pathogenic, which means they are disease causing, and they are also microorganisms, which means that they are very small so the human eye cannot see them.
1. Normally, the immune system protects the body from infection by identifying and destroying bacteria,
Bacterial and fungi infections are easy to cure with the use of antibiotics, where as viruses can be hard to cure or vaccinate against, such as the common cold. Bacteria can be found everywhere and anywhere Soil, Water, Plants, Animals, material and even deep in the earth's crust. Bacteria feed themselves by making there food with the use of sunlight and water. We would not be able to live without Bacteria. The human body consists of lots of friendly bacteria which also protect us from dangerous ones by occupying places in the body. Some of the most deadly diseases and devastating epidemics in human history have
Epidemiologists use a tool called, epidemiologic triangle to help understand infectious disease. “The epidemiologic triangle is a traditional model that characterizes infectious disease causation” (Merrill, 2017, p. 178). The triangle consists of an external agent, a susceptible host, and an environment that brings the host and the agent together. The agent, or the “what” of the Triangle, is the cause of the disease. The host or the “who” of the Triangle, can be the organism that gets sick, as well as any animal carrier (including insects and worms) that may or may not get sick. The environment, or the “where” of the Triangle, is the favorable surroundings and conditions external to the host that cause or allow the disease to be transmitted.
If a pathogen breaches barriers: innate immune response result into an immediate effect of non- specific response. All Innate immune systems derived from plants and animals, when a pathogen evades the innate response, a third layer of protection is possessed by vertebrates in which activation of adaptive immune system takes place. The immune system response adopts itself within an infection and pathogen recognition is improved. As a result of the improved response, its then retains itself when the pathogen is eliminated in form of an immunological memory and allows the adaptive immune system to mount faster and stronger when pathogen is encountered each time.
Once a pathogen is inside its host, it must evade recognition and killing by the host’s immune system. As the pathogen
Pathogens can only cause infectious diseases to the human body when inside. There are three fundamental interfaces with the environment that pathogens can enter the human body which incorporate breathing in air that contains pathogens through the gas exchange system, digestive system; eating or drinking and harm to the skin being a cut or swelling. A pathogen is any organism that causes illness which incorporate microorganisms and some bigger living beings, for example, tapeworms. Pathogenic microorganisms incorporate little bacteria, little fungi and all viruses (Parsons, R, 2008, P.5).
The term virulence is one that describes the amount of damage or harm an organism does to its host. Paul Ewald, a pioneer of evolutionary biology, has discovered how virulence is tied up with the type of transmission method. There are different degrees to virulence from harmless pinworms to extremely dangerous Ebola. Ewald believes that organisms that rely on close proximity for transmission need a host that is healthy enough to be mobile. These microbes depend on the host for easy access to new hosts. This explains why people who have the cold are still able to get up and do things even though they are ill. On the opposite end of the spectrum are diseases and organisms that don’t need its host to get around. In the case of malaria it incapacitates
The Human Immune system is made up of a variety of chemical and cellular components that are classified as either innate or adaptive immunity. The cellular immune response to the bubonic plague is carried out through the innate response as the bacterium is able to avoid the adaptive response by infecting macrophages in the host’s body. Similarly, the immune response to HIV infection is not able to reach the adaptive response, as the virus infects the body and destroys vital CD4 cells which in turn damage the immune system itself. Furthermore, the immune system relies heavily on the action of B and T cells, which are antigen-specific cellular immune responses to battle the HIV virus. Though it is unable to completely rid the host of the virus,
A Type 1 immune response will be induced upon the reintroduction of the virus with recognizable A and C epitopes and with the new D and E epitopes that were not expressed by the initial virus. I believe this individual would experience the “Original Antigenic Sin,” which is when one’s body has the primary tendency to make antibodies only against the first A, B, and C viral epitopes. Moreover, antibodies from the original A, B, and C epitope virus tend to inhibit or suppress responses of naïve B cells specific for that new A, C, D, and E epitope. Furthermore, this might be beneficial for the individual because when one’s body only uses those B cells that can effectively respond rapidly, this can lead to a better immune response.
Pathogens are everywhere. They are in people, animals, and the environment. Pathogens come in a wide variety. The types are fungal, bacterial, viral, and other parasites. All pathogens can be dangerous, but two of them are more dangerous. These two types that more dangerous are fungal and bacterial. While both fungal and bacterial pathogens cause illness, they differ in the way they are transmitted, the way they are treated, and the diseases they cause.
Infectious disease is the result of complex interactions between the biological agent, the host, and their environment. This is often viewed as a triad {Anderson, May, 1982}. (Ryan, 2009).
Food contamination. Another way disease-causing germs can infect is trough contaminated food and water. This mechanism or transmission allows germs to be spread to many people through a single source. For example, is a bacteria present in or on certain foods; such as undercooked hamburger or unpasteurized fruit juice.
Introduction: The extent to the pathogenesis of the human immunodeficiency virus 1 (HIV-1), or “HIV”, has been studied for years. It is of large consensus to the medical community that any strong predictor of the time showing phenotypic characteristics of HIV from the original transmission of the disease can be predicted through assessing and evaluating the set-point viral load (SPVL). Depending on the subsequent viremia in the blood, biologists and medical professionals can strongly predict the severity of the infection and future clinical outcomes.