Groundbreaking Research Papers

A second model to understanding disease transmission is termed chain of infection. This model illustrates the pathway from the source of the disease or pathogen to the new host. The chain of infection for contagion would be: the MEV-1 virus (pathogen) exiting through the swine’s body (reservoir), more specifically the infected blood (portal of exit) into the hands of the casino chef (transmission link) and later the hands of “Beth”, the American host, which would establish a new portal of

Transmission usually occurs as the result of the introduction of E. coli containing feces into the oral cavity of the host. Known as fecal-oral transmission, this type of transmission is primarily responsible for the spread of E. coli from animals to humans. The transmission of E. coli to humans occurs by direct contact, ingestion of water or food contaminated by the spread of manure, or consuming undercooked meat after fecal contamination of the carcasses at the slaughterhouse. For a diagram of the transmission life cycle of E. coli, see Appendix 5. For a comprehensive diagram outlining the various transmission methods, refer to Appendix 6.

See Table 1 and Flow Chart 1 for results of Bacteria # 1 and Table 2 and Flow Chart 2 for results of Bacteria # 2.

Often scientists work with bacteria that do not come in a labeled test tube— for example, bacterial samples taken from infected human tissue or from the soil—and the scientist must then identify the unknown microorganism in order to understand what behavior to expect from the organism, for example, a certain type of infection or antibiotic resistance. However, because of the relatively few forms of bacteria compared to animals and because of the lack of bacterial fossil records due to their asexually reproductive nature, the taxonomy used to classify animals cannot be applied to bacteria (Brown 275). In order to classify unknown bacteria, a variety of physiological and metabolic tests are available to narrow a sample down from the fathomless number of possibilities into a more manageable range. Once these tests have been performed, the researcher can consult Bergey’s Manual of Determinative Bacteriology, a systematically arranged and continually updated collection of all known bacteria based on their structure, metabolism, and other attributes.

Indirect transmission of infectious organisms involves vehicles and vectors which carry disease agents from the source to the host.

Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of the very nature of this ubiquity, it is important to be able to determine between different strains of bacteria. An example of this is determining the causative agent for a disease so that the patient will be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic infections in places outside of the digestive tract to our detriment, such as with a urinary tract infection. Some strains of bacteria are common to nosocomial infections, and identifying these bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the morphology and characteristics of each strain of bacteria help us to better understand the role of bacteria in the body as well as helps us understand how they can cause illness, and what treatment regimen to set in place. In lab this semester, a sample of unknown

The spread of infection requires three elements. The first is; A source of infecting microorganisms: This could be an exogenous infection which arises from microorganisms external to the individual and do not exist as normal flora. They usually have a preferred portal of entry like the gastrointestinal for Salmonella. Another source is endogenous infections which can occur when part of the client’s flora becomes altered and an overgrowth results e.g. Yeasts infection. Second requirement is means of transmission for the microorganism, which also explains the three primary modes of pathogen transmission. For example, vertical transmission is when a pathogen is

There are approximately 3.3 million genes (according to the European’s census of microbial genes) in the human digestive system. In comparison, it is about 150 times the count of 20,000-25,000 genes our own gene.

There are major effects in the United States and Europe to help identify the role of microbial communities in the human body. The colon requires a balance of microbial agents that assist with various functions of the body. An imbalance can lead to C.diff., irritable bowel disease (IBD), irritable bowel syndrome (IBS), neurological disorders, and obesity just to list a few. Many of these problems have grown to an epidemic proportion. Both the United States and Europe have started projects aimed at the microbial communities of the body and their roles in our health.

It may be a virus or bacteria that would cause an illness. The reservoir is the place where the pathogen may adhere to live and survive. It can be a person, animal, or environmental component such as water or soil. The portal of exit is the invasion or place where the pathogen may leave the reservoir. It can be saliva, mucous membranes, feces, blood or any discharges coming out from the body. The means of transmission can be directly or indirectly transmitted. Direct transmission requires close association with the infected host, but not necessarily physical contact. Indirect contact requires a vector, such as an insect or animal. The portal of entry can be done in three ways: penetration or a cut to the skin, inhalation, or ingestion. Then it is already in the new host, which will have various factors on how the host will be affected by its severity and will also depend on the health and well being of the

A communicable disease chain is the mechanism by which an infective agent or pathogen is transmitted. The chain requires an infective agent, a source of infection, a mode of transmission and a host. An example of an infective agent could be bacteria, a virus, fungus, protozoan or helminth. The source of infective agents can be transmission from host to host, an infected human or animal, insects, soil or livestock. The mode of transmission is how the infective agent is carried from host to host. Transmission can be by air, ingestion or physical contact. To complete a life cycle or to replicate, the infective agent requires a host.

However, the scene is changing dramatically once again, and not in our favor. Antibiotic resistant bacteria

The transmission of this infection is known to be passed from one individual to another by the faecal – oral route.

All over the world we have been putting antibiotics into everything imaginable. Things like dog food, air fresheners and even garbage bags in an attempt to stop bacteria from spreading in our homes. But instead of killing the bacteria once and for all we may just be making them stronger. Every bacteriologist’s nightmare is coming true. Bacteria are beginning to be almost impossible to kill.

Over two decades ago, researches at Umea University in Sweden made an astounding discovery. They found out that bacteria can multiply disease-inducing genes that are essential to spread the infection quickly, focusing on a particular bacteria called Yersinia and on its structure called T3SS that allows it to transfer bacterial proteins into the host cell and destroy its metabolism. The T3SS is made up by more than 20 proteins that are membrane embedded. When the infection process starts, the bacteria receive an external signal from the host environment and begin to assemble the constituents of the secretion system. The characteristic of T3SS is the needle also called injectisome. The Bacterial proteins pass from the bacterial cytoplasm through the needle into the host cytoplasm, there are three membranes between the two cytoplasms .The needle provides a smooth passage through membranes, it starts at the cytoplasm of the bacterium pass through the two membranes and projects from the cell,