Introduction
H. capsulatum is a most common true pathogen that causes histoplasmosis, and was discovered by Dr. Samuel Darling in 1905 (Talaro & Chess, 2012). Histoplasma capsulatum is a dimorphic fungus that can grow in human bodies as yeast. It is known to grow best at human body temperatures, and it remains in a mycelial form at ambient temperatures (Fayyaz, 2013). Most individuals who inhale this microscopic fungal spore don’t get infected, however some individuals who inhale this spore result in developing lung infections. H. capsulatum is a fungus that can be found in the soil, and is associated with bird and bat droppings (CDC, 2013). It is interesting that it took so long after the discovery for its epidemiology to now suggest that it has been present for as long as agriculture is practiced (Talaro & Chess, 2012).
Causal Agent
Histoplasma capsulatum is a microbial fungus that is mostly involved in lungs and belongs to the kingdom fungi. The main target of these inhaled spores are the lungs. By targeting the lungs the spores can cause some individuals to developing minor or severe lung infections (CDC, 2013). Histoplasmosis is an airborne infection, which is transmitted when an individual inhales the spores when disruption of soil or materials contaminated with bat or bird droppings takes place.
Epidemiology
Histoplasmosis disease is primarily found in the eastern and central regions of United States. Specifically, it can most commonly be found in the Ohio Valley, and other areas with moist soils that have high levels of bird and bat feces (Talaro & Chess, 2012). Since the Histoplasma capsulatum is much associated with soil and bird feces, it is very common among individuals who are working in parks, bird roosting areas, ...
... middle of paper ...
...of histoplasm's virulence factor CBP. Retrieved February 26, 2010, from http://pubs.acs.org/doi/abs/10.1021/bi701495v#fn1
CDC (2013), Histoplasmosis. http://www.cdc.gov/fungal/diseases/histoplasmosis/index.html
Edwards JA & Rappleve CA. (2011). Histoplasma mechanisms of pathogenesis-one pertfolio doesn’t fit all. Retrieved 2011 by PubMed http://pubmedcentralcanada.ca/pmcc/articles/PMC3228276/
Fayyaz, J.(2013). Histoplasmosis. Retrieved 1994-2014 by WebMD: http://emedicine.medscape.com/article/299054-overview
MedScape (2013). Amphotericin B. http://reference.medscape.com/drug/fungizone- amphotericin-b-conventional-amphotericin-b-deoxycholate-342582
MedScape (2013). Itraconazole. http://reference.medscape.com/drug/sporanox-omnel- itraconazole-342591#0
Talaro KP & Chess B. (2012). Foundations in Microbiology: Basic Principles. 8th edition. McGraw-Hill.
The population of bats in the United States is facing a serious threat of extinction due to the outbreak of a deadly fungus called Deomyces destructans. The fungus is nicknamed White-Nose Syndrome, after the white fungus that typically appears on the infected bats noses and wings. Other signs and symptoms of White Nose Syndrome are white fungus on the ears and tail as well, bats flying during the day in the middle of winter, bats clustered near the entrance to a hibernacle or cave, and general abnormal behavior for a hibernating bat. Scientifically the fungus has been identified as, Deomyces destructans. The fungus itself causes damage to their connective tissues, muscles, and skin. It also can disrupt many of their physiological processes. Typically during a hibernation period bats will wake up on average every 10 to 20 days. An infected bat on the other hand will wake up every 3 to four days which causes them to burn up their fat stores twice as fast. When they wake up they are both dehydrated and hungry, around 90% of the bats actually die from starvation due to a lack of insects for food in the winter season. WNS is transmitted from bat to bat and that is why any contact between an infected bat from one cave population with a non-infected bat from another population has serious consequences.
After a series of biochemical tests and evaluation to determine several unknown bacteria, the bacterium Yersinia pestis was chosen to report. The discovery of Y. pestis dates back to 1894 by French/Swiss physician and bacteriologist named Alexandre Yersin. The name Yersinia pestis is synonymous with its more common name, the plague. Y. pestis is known to infect small rodents such as mice and rats, but is transmitted to humans through the bite of an infected animal or flea. Although this bacterium is known to still cause illness today, it is infamous for three pandemics that occurred in earlier centuries. According to the Centers for Disease Control and Prevention, the first recorded pandemic occurred in 541 A.D. and is known as the Justinian Plague. The second pandemic originated in China in 1334 and has received the egregious name the “Black Death.” Finally, the third outbreak took place in the 1860’s and is known as the Modern Plague. It wasn’t until the end of the Modern Plague that scientists discovered the causative agent and mode of transmission of the Yersinia pestis bacterium.
This final microbe is far less dangerous and easier to comprehend than the formerly mentioned ones. Histoplasma Capsulatum, often called histoplasmosis, is caused by a fungus called Histoplasma (1). This fungus thrives within earthy environments with lots of soil filled with bird and bat droppings (1). It is found mainly in the United States, specifically within the central and eastern states, such as around the Ohio and Mississippi river valleys (1). The fungus can also be found within central and South America, Africa, Asia, Australia, and small parts of Europe (1). While most people do not get sick, those who do become infected when breathing in the microscopic fungal spores in the air (1). Symptoms
Tibbetts, John. "Environmental Health Perspectives." January 2006. Louisiana-A lesson in Nature Appreciation Vol. 114, Number 1. 4 December 2010 .
Schistosomiasis is a parasite. This parasite is a worm that you get through contaminated water. Urine and feces usually contaminate the water. The worm goes in to your body and migrates to the bladder, rectum, liver, lungs, spleen, intestines and some veins. After the worm migrates to these places this is where it matures and lays its eggs. The disease has the ability to lay two thousand to three thousand eggs per day and can live for twenty years. There are five different kind of Schistosomiasis that effect humans, these different kinds are; S. mansoni, S. Heamatobium, S. japonicum, S. intercalatum and S. mekongi. There are also other kinds of Schistosomiasis that occasionally infect humans, there are; S. bovis, S. mathei, and some avian schistosomes.
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.
Disease and parasitism play a pervasive role in all life. Many of these diseases start with microparasites, which are characterized by their ability to reproduce directly within an individual host. They are also characterized by their small size, short duration of infection, and the production of an immune response in infected and recovered individuals. Microparasites which damage hosts in the course of their association are recognized as pathogens. The level of the interaction and the extent of the resultant damage depends on both the virulence of the pathogen, as well as the host defenses.
This more severe form usually prevails in elderly, cigarette smokers, people with chronic lung disease, or those who are immunocompromised, such as cancer or AIDS patients. Virulence:.. Being a gram-negative bacterium, L. pneumophila has lipopolysaccharides (LPS) that act as endotoxin within a human host. The presence of a flagella is thought to mediate adherence to human lung cells, thereby causing infection, since flagella-less strains do not cause disease. Once attached to human cells, the organism is engulfed by a macrophage that utilizes the internal environment to multiply.
Wharton, David A. "Toxoplasma Gondii Prevalence in Farm Animals in the United States." International Journal for Parasitology: ASP Special Issue : 2000 Joint Meeting of the New Zealand Society for Parasitology and Australian Society for Parasitology Te Papa, Wellington, New Zealand, 24-28 September 2000. 2nd ed. Vol. 43. Oxford: Elsevier Science, 2001. 107-13. Print.
Toxoplasmosis is a disease caused by Toxoplasma gondii, a single celled parasitic organism, one of the world's most common parasites, infecting most warm- blooded species. The only known hosts for the protist are members of family Felidae (domestic cats and their relatives).
Only the smallest particles of the coal dust make it past the nose, mouth, and throat into the alveoli found deep in the lungs. The alveoli, or air sacs, are responsible for exchanging gases with the blood, and are located at the end of each bronchiole. Microphages, a type of blood cell, gather foreign particles and carry them to where they can either be swallowed or coughed out. If too much dust is inhaled over a long period of time, some dust-laden microphages and particles collect permanently in the lungs causing black lung disease.
Necrotizing Fasciitis (flesh eating bacteria ) from an essay by Katrina Tram Duong, edited by S.N. Carson M.D.
"Bloodborne Pathogens : MedlinePlus Medical Encyclopedia." U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 09 Feb. 2014.
In the spring of 1993, there was a massive widespread outbreak of acute watery diarrhea among the residents of Milwaukee. The results of the case presented indicate that this massive outbreak of watery diarrhea was caused by cryptosporidium oocysts that passed through the filtration system of one of the city's two water-treatment plants of Milwaukee Water Works (MWW). It was estimated that more than 400,000 people were affected during this outbreak. Milwaukee Department of Health reported numerous cases of gastrointestinal illness that resulted in absenteeism among employees and students of that area. Laboratory testing for 739 people’s stool samples identified cryptosporidium oocysts. Randomly selected people, who were identified as having clinical cryptosporidium infection, were contacted to conduct a telephone survey. Laboratory-confirmed cases of cryptosporidium infection compared to those who had clinical characteristics with cryptosporidiosis had significantly longer duration of diarrhea and more frequent bowl movements, vomiting, fever, and fatigue. Both groups had similar epidemiologic features and dates supporting the hypothesis stated in this study that the group who was interviewed through the phone survey had clinical cryptospori...
Tuberculosis is transmitted by inhalation of aerosols containing the tubercle bacilli. The required inoculum size for infection is usually high, but easily occurs with exposure to a patient who is currently infected. The products of dried aerosols, droplet nuclei, are particularly infectious because they remain in the air for an extended time, and upon inhalation easily move to the alveoli. The severe damage related to infection is caused by the reaction of the host. The tuberculosis infection has two phases, primary and secondary.