Various recovery techniques for Legionella were used in the methodology of this study. With regards to the sample collected, two primary sample types (water and swab sample) from each faucet were gathered and tested for the presence of the organism. The type of sample which showed a higher isolation rate of Legionella was the swab sample over the bulk water sample. Moreover, the highest CFU/L recorded was also from the swab sample (faucet ). These results could be explained by the fact that Legionellae survive within biofilms, the most likely sample collected when swabbing a faucet compared to flowing water (Rogers JA, et. Al, 1994). In this case, the probability of isolation of the organism increases due to its better survival in biofilms as well as concentrated amount in this material. For the treatment method used, the technique which allowed the highest recovery of the organism was the one using heat treatment. This decontamination process yielded the most number of Legionella isolates from both the swab and …show more content…
organism in the samples. The filtration isolation technique and the treatment methods used to eliminate other microorganisms in the water have an effect in the reduction of few viable Legionella that may be present in the samples. The concentration of the water sample using filtration increased the sensitivity of the method, but not the specificity. According to several studies, filtration brings about a reduction in detectable Legionellae of 16-91% (Brindle et al., 1987; Boulanger and Edelstein, 1995; Ta et al., 1995). While the decontamination with acid buffer and heat, which increased the specificity to Legionella, lead to a decrease in isolated Legionellae between 5 and 99% (Boulanger and Edelstein, 1995; Roberts et al., 1987). The samples may possibly harbor the organism, but the process of filtration and treatment performed may have killed the
The first day an unknown sample was assigned to each group of students. The first test applied was a gram stain to test for gram positive or gram-negative bacteria. The morphology of the two types of bacteria was viewed under the microscope and recorded. Then the sample was put on agar plates using the quadrant streak method for isolation. There were three agar plates; one was incubated at room temperature, the second at 30 degrees Celsius, and the third at 37 degrees Celsius. By placing each plate at a different temperature optimal growth temperature can be predicted for both species of bacteria.
They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species.
Question 1: How is salmonellosis diagnosed? How does the method of diagnosis impact our understanding of the occurrence of salmonellosis in the community (e.g., burden of disease, trends over time, high-risk populations)?
ABSTRACT: Water samples from local ponds and lakes and snow runoff were collected and tested for coliform as well as Escherichia coli. Humans as well as animals come into contact with these areas, some are used for recreational activities such as swimming and some are a source of drinking water for both animals and humans The main goal of this experiment was to see which lakes, snow run off and ponds tested positive for coliform or Escherichia coli and to come up with some reasoning as to why. It was found that the more remote pond with less contact contained the most Escherichia coli. However, another lake that many swim in and use as their drinking water indeed tested positive for a small amount of Escherichia coli. The two samples from the snow showed negative results for both coliform and Escherichia coli and the two more public ponds that aren’t as commonly used as a source of human drinking water but animal drinking water tested in the higher range for coliforms but in the little to no Escherichia coli range. It was concluded that the remote pond should be avoided as it’s not a safe source of drinking water for humans or animals. Other than that, the the other ponds are likely to be safe from Escherichia coli, but coliforms are a risk factor.
The guidelines’ first focus is the definition of sepsis, which makes sense, because there is no way to effectively treat sepsis without an accurate and categorical definition of the term. The guidelines define sepsis as “the presence (probable or documented) of infection together with systemic manifestations of infection”. Such systemic manifestations can include fever, tachypnea, AMS, WBC >12k, among others; these manifestations are listed in full in Table 1 of the guidelines. The definition for severe sepsis builds on to the definition of sepsis, bringing organ dysfunction and tissue hypoperfusion (oliguria, hypotension, elevated lactate) into the picture; full diagnostic criteria is listed in Table 2. The guidelines recommend that all
My disease is Streptococcal pneumonia or pneumonia is caused by the pathogen Streptococcus pneumoniae. Streptococcus pneumoniae is present in human’s normal flora, which normally doesn’t cause any problems or diseases. Sometimes though when the numbers get too low it can cause diseases or upper respiratory tract problems or infections (Todar, 2008-2012). Pneumonia caused by this pathogen has four stages. The first one is where the lungs fill with fluid. The second stage causes neutrophils and red blood cells to come to the area which are attracted by the pathogen. The third stage has the neutrophils stuffed into the alveoli in the lungs causing little bacteria to be left over. The fourth stage of this disease the remaining residue in the lungs are take out by the macrophages. Aside from these steps pneumonia follows, if the disease should persist further, it can get into the blood causing a systemic reaction resulting in the whole body being affected (Ballough). Some signs and symptoms of this disease are, “fever, malaise, cough, pleuritic chest pain, purulent or blood-tinged sputum” (Henry, 2013). Streptococcal pneumonia is spread through person-to-person contact through aerosol droplets affecting the respiratory tract causing it to get into the human body (Henry, 2013).
Salmonella Infection. "Treatments and Drugs." Mayo Clinic. 12 April. 2007. Mayo Foundation. 27 July. 2008 .
Legionnaires’ disease is an infectious disease caused most often by the bacteria Legionella pneumophila (L. pneumophila). The disease resembles severe pneumonia. Legionnaires’ disease is sometimes called “Legion Fever.” It was first discovered in 1976 when there was a pneumonia outbreak among people attending a convention of the American Legion in Philidelphia. In January of 1977 the bacteria was discovered as the causative agent of the outbreak. While outbreaks receive substantial media attention, thousands of people are exposed to the bacteria each year and never have any serious signs or symptoms of the disease. The elderly, immunocompromised and smokers are the most susceptible. Most outbreaks that do occur are in the summer when water temperatures naturally rise. Fatality rate of the disease ranges from 5 to 30 percent (The Mayo Clinic, 2008).
“Legionnaires’ disease is a bacterial infection caused primarily by the species Legionella pneumophila, it was initially recognized as the cause of a 1976 outbreak of respiratory disease outbreak in Philadelphia. Legionellosis infection occurs after persons have breathed mists that come from a water source. The most recent outbreak of Legionnaires’disease is in New York City, in the Bronx, with a total of ten deaths and more than one hundred outbreaks, which were traced to a cooling tower, deaths have also been reported in Michigan, and Ohio.
Legionella pneumophila GRAPH Introduction: Legionella pneumophila are gram-negative rods. They are very difficult to culture because of their complex nutrient requirements, such as cysteine, high concentrations of iron, and the use of activated charcoal agar. They survive as intracellular pathogens of either protozoa or human macrophages. They are most often found in stagnant water reservoirs like air conditioning cooling towers, whirlpool spas, humidifiers, faucets and shower heads, and are infectious when inhaled. L. pneumophila was first identified and named after the American Legion convention of 1976, held in Philadelphia, PA.
“Salmonella Questions and Answers.” USDA Food Safety and Inspection Service. 20 Sept. 2006. 20 July 2008 .
Comment on class result with respect to differences in filter types, differences in filter assemblies, and overall on the confidence you would have in using this type of sterilisation process in preparation of pharmaceutical products. List the factors that may cause contamination during filtration. (20 marks)
Over the years humans have tried every possibility to overcome the health problems, spread of epidemics and infections, disease control and have worked towards a healthy society free of disease and health problems. They have succeeded to a great extent. The book “Good germs, bad germs” describes that though the life expectancy is now far more as it was in previous eras. Epidemic problems and infectious diseases are now getting lesser and lesser and humans are being treated successfully. The hygienic conditions have also been improved so as to ensure least growth of microbes, germs, parasites and bacteria. Antibiotics have been invented to address diseases and infections caused by bacteria and viruses. With all these substantial efforts the biologists, physicians and scientists have triggered another epidemic which is even more severe. They have killed those microbes and bacterial species which were human friendly and as a result of either their disruption or mutation, pathogenic bacteria have even become more active and resistant to treatments. This has led to increased ineffectiveness of antibiotic drugs, low immunity and various infections and inflammatory diseases. The chlorinated water for drinking and food processing along with excessive hygienic conditions indicates our fight against these bacteria and germs. Further, these antibiotics are even given to the livestock which becomes our food and as result many of their resistant germs end up in our digestive tract and other organs. Thus, the war against microbes through excessive cleanliness and use of antibiotics has resulted in antibiotic resistance among humans, which has become one of the prominent problems of medical science
Biofilms can form on many surfaces, including natural aquatic systems, human teeth, medical devices like artificial heart valves and catheters,
Biofilms are formed on almost any surface that is submerged in non-sterile water. Even hot springs, and glaciers. Examples of common places where biofilms are found are pipes, hulls of ships, porcelain surfaces of toilet bowls, wood siding, shower tiles, plastics, wooden cutting boards, vases, marine and fresh water environments, soft tissue surfaces in living organisms, contact lenses, mascara brushes, eye care solutions, and artificial fingernails. A sufficient amount of moisture, nutrients, and a large smooth surface must be present for a biofilm to form. The more nutrients there are, chances are, the more rapid the development will be.