Cause And Treatments Of Typhoid Fever Infections Biology Essay

Cause And Treatments Of Typhoid Fever Infections Biology Essay The burden and rigourness of typhoid fever infections caused by Salmonella enterica serovar Typhi is a substantial universal populace concern, particularly in developing countries (Demczuk, Finley, Nadon, Spencer, Gilmour NG, 2010). It is a systemic infection primarily involving the alimentary tract (Christopher, 2002). It has been found that humans are the only natural reservoirs of S. Typhi, with contagion occurring through consumption of faecally contaminated food and water (Corner Schwartz, 2005) or in other words, it occurs where there is substandard water supply and sanitation. It has been estimated by WHO that the annual global incidence of typhoid fever is at 0.3% (Demczuk et.,al, 2010). It has been estimated that annually 6, 00,000 deaths occur from enteric fever worldwide. S. Typhi infections may cause symptoms like bacteraemia, fever, headache, malaise, abdominal distress, diarrhoea and rose colored spots which contains the infecting organism (Chamberlain, 2006). Typhoid fever is preventable through vaccination prior to travelling to areas where typhoid is common and careful consumption of food. Treatment with appropriate antibiotics can also prevent complications. S.typhi first of all invades the alimentary canal by ingestion then via the lymphatic system and the thoracic duct into the stream of blood. This first septicaemic phase leads to infection of the reticulo-endothelial system and the gall bladder. When the infection of the gall bladder occurs, there is discharge of organisms into the intestine, with heavy infection of the Peyers patches and septicaemia- and the onset of symptoms (Sleigh Timbury, 1998). Most of the symptoms which are caused by S.typhi can be ascribed to the inflammation caused by its lipopolysaccharide as it does not have any specific known endotoxins. After an incubation period of 10-14 days, early symptoms like fever, headache and respiratory symptoms appear. Then, mild abdominal pain with either diarrhoea or constipation occurs. After that, fever increases in a stepwise fashion. Without treatment, the patient may eventually lapse into a stupor and the problem may persist for 4 to 6 weeks. A serious problem that is secondary invasion of the intestine from the gall bladder which can cause perforation of the intestine. In 15% of untreated cases, death may also occur. Typhoid fever can be diagnosed by the laboratory tests to find the bacteria in the blood or faeces of an infected person. Illness is usually characterized by fever, loss of appetite, lethargy and change in bowel habit. Constipation is common in the initial stages but diarrhea can also occur. The diagnosis of enteric fever relies on the isolation of S.typhi from the patient. Specimens include faeces, blood and urine. The culture used for blood and urine is MacConkey medium in which enrichment and the selective media are not necessary. Blood culture is positive in more than 80% of patients in the first week of illness. Faeces should also be cultured especially at 2-4 weeks after onset of symptoms, when seeding of the kidneys and secondary infection of the intestine occurs. For faeces, indicator medium is used for non-lactose-fermenting colonies and selective and enrichment media for others (Sleigh Timbury, 1998). Identification can be done by the Biochemical reactions (API test). In this test, unlike other salmonellae, S.typhi produces no gas on fermentation of sugars. In serological identification, first of all preliminary diagnosis with salmonella polyvalent H and O antisera is done and after that final identification is done from where it is send to the Reference Typing Laboratory. Phage typing is also useful in identifying the different types of S.typhi for epidemiological identification into the source of outbreaks. Serum antibodies to the organisms can be detected by an agglutination test known as Widal test, but positive results must be interpreted with care where past exposure or vaccination are possibility. A fourfold rise in titre between acute and covalescent sera is diagnostic. The salmonella bacterium resides in the human gut. The source of infection is the carriers or the cases that excrete the organism: excretion in faeces and less commonly in the urine. The infection continues for about two months after the acute illness. The route of infection is through the ingestion of water or food which is contaminated by sewage or via the hands of a carrier. Direct spread from case to case is rare. Only a small number of these bacteria can cause typhoid fever. This is the main reason that water-borne infection is common, despite the dilution of organisms. The following are High risk groups for developing Typhoid Fever: Travelers with individualistic lifestyle and those are intending prolonged travel to areas where there is typhoid fever. Former migrants from developing countries who are visiting their parent countries. Those with no acid or low acid concentrations in their stomach such as post surgery or with regular use of antacids and medication to reduce stomach acidity. Those with sever or ongoing disease may need particular advice about typhoid fever and where the intended travel is to be Travelers to the Indian Subcontinent Medical personnel, foreign aid workers and military personnel assigned in developing countries. Outbreaks of typhoid fever are often explosive- sometimes involving large number of people. There are two main types of outbreak: Water-borne: in which the organisms from the sewage acts as a carrier and pollutes the drinking water, e.g. the outbreaks in Croydon in 1937 and in Zermatt in 1963. Food- borne: in which food becomes contaminated via polluted water or via the hands of the carriers. Typhoid Mary, possibly most famous carrier, worked as a cook in USA and caused number of outbreaks. Tinned food may also become contagious during canning- the large outbreak in Aberdeen in 1964 was due to a tin containing corned beef which had been cooled in water contaminated by sewage; bacteria entered the can through tiny holes in the metal casing. Shellfish often grow in estuaries, where the water may be contaminated by sewage: if it is eaten uncooked they may cause infection. Milk or cream products, contaminated through the handling of the carriers, have caused outbreaks of typhoid fever. Other food products like meat, dried and frozen foods, dried coconut have also been responsible for infection. Antibiotics are a type of medication effective in treating infections caused by bacteria based on signs and symptoms. Oral treatment with chloramphenicol, ampicillin, cotrimoxazole or ciprofloxacin is generally effective and should be maintained for 14 days to reduce the possibility. But resistive strains to above antibiotics have also been reported, particularly on Indian subcontinent (Lee Bishop, 2010). For chronic carriers, long term therapy with ampicillin or ciprofloxacin may be effective but, if not, cholecystectomy (removal of gall bladder) may be warranted. Chloramphenicol is a bacteriostatic antibiotic with wide spectrum of activity against gram-positive and gram negative cocci and bacillus. It binds to the 50S subunit of the ribosome and inhibits bacterial protein synthesis. Ampicillin is a broad spectrum semi-synthetic derivative of aminopenicillin that inhibits bacterial cell wall synthesis by binding to penicillin binding proteins and inhibiting peptidoglycan synthesis, a critical component of bacterial cell wall. Ciprofloxacin is a synthetic broad spectrum fluoroquinolone antibiotic which inhibits bacterial DNA gyrase, an enzyme essential for DNA replication. This agent is more active against Gram-negative bacteria than Gram-positive bacteria. It is very difficult to eradicate S.typhii from the gall bladder. Antibiotic treatment is effective in curing some carriers, but still to some extent the infection persists and they become long-term permanent carriers. Promising results have been given by ciprofloxacin. For the high risk groups, two effective typhoid vaccines: the oral live vaccine (Ty 21a) and the injectable Vi capsular polysaccharide vaccine is highly recommended. The live attenuated vaccine Ty 21a is a strain of S.typhi. It is indicated for those who travel to or living in areas where typhoid is an endemic and where the health care staff is at risk. It is administered in enteric-coated capsules orally in three doses on alternate days. Some mild adverse reactions may also persist like nausea, vomiting etc. This vaccine is quiet efficient but may be less durable. The other type of vaccine is a classic type killed vaccine which has now been replaced by other preparations but still it is being widely used. It contains heat killed phenol preserved suspension of S.typhi. It is injected and two doses need to be consumed 4-6 weeks apart and booster doses need to be taken every 3 years. In consuming this, some local and general reactions are common which vanishes after 36 hr from the onse t. In New Zealand, the injectable Vi Polysaccharide vaccine (Vi antigen) is recommended for all adult children over the age of 2 years travelling to areas where there is questionable sanitation. It is known that children under the age of 2 years may show a sub-optimal response to polysaccharide antigen vaccine. It gives approximately 70% protection against the disease. There are two products available in New Zealand and Australia: Typherix (GlaxoSmithKline) and Typhim Vi (MSD [NZ] Ltd). They are interchangeable. The infection prevention and control team plays a vital role in preventing cross infection and prevention of hospital acquired infection. In order to ensure that infection is not caused, the surveillance team should keep highest level of vigilance in which phenomenon like proper aseptic techniques, hand hygiene practice should be followed. Furthermore, following preventive measures should be followed: Wash and dry hands thoroughly after using the toilet or changing nappies. Hands should be washed for 20 seconds and dried for a further 20 seconds using a clean cloth or disposable towel. Soiled clothing and linen should be washed with hot soapy water separately from that of other family members. Items such as face cloths and towels should be kept for personal use. A person with Typhoid infection should avoid preparing food for others in the family until they are no longer infectious. In households where a person is recovering from typhoid, toilet seats, flush handles, wash basin taps and toilet door handles should be disinfected daily using a hypochlorite based solution. Ideally the solution should be in contact with the surface of the object for at least  ½ hour. Drink bottled, purified or carbonated water for drinking and cleaning teeth. Make sure that bought bottled water is appropriately sealed; regular water (sea level) should be brought to boiling point for one minute before it is safe to drink. Avoid ice in drinks and remember that refreshing ice blocks and flavored ices may be made with contaminated water. Foods should be thoroughly cooked and served piping hot. Be very wary of food sold by street vendors. Avoid raw seafood and shellfish; even though they may have been preserved with vinegar, lemon or lime juice. Choose raw vegetables and fruits that a person can peel himself. Avoid salads unless they have been made by own. Do not forget to wash hands with soap or hand cleaner first and not to eat the peelings. Antimicrobial resistance surveillance is also a significant activity which needs to be practiced. Moreover, as the economies of the developing countries grow the sanitary conditions of currently typhoid- endemic countries will improve. Due to that, number o f typhoid fever cases will lessen. However, in order to expedite the elimination of typhoid fever, Member States and WHO will strengthen their power for typhoid fever surveillance by improving laboratory-based surveillance. Intersectoral collaboration at both national and international levels will be essential if the disease needs to be controlled in endemic countries. In conclusion we have discussed in brief the organism- S.typhi, the laboratory diagnosis, its epidemiology, antibiotic treatment and finally the role of the infection control and prevention team in controlling the infection.

Yoga for Eye Sight

The great master Swami Vivekananda said that there are four main streams of yoga:Jnana Yoga, Raja Yoga, Bhakti Yoga and Karma Yoga. To use all these streams of yoga to build the personality. We are now going to focus on Eyesight Development or Eyesight Improvement. In late 60s the TV came afresh in Bangalore city and everybody was so fascinated, particularly the children glued themselves to TV forgetting all their sports outside. Went on watching 3 hours, 4 hours, 5 hours, 6 hours and movies after movies and as expected it started happening in 5 or 6 years, 1972-73 we started seeing most of these children wearing very thick glasses.We felt too bad. We said can we solve this problem? Many people said that we are not going to allow our children to watch the TV. That is no solution. This is when we started developing yoga module. The specialised techniques that yoga prescribes for eyesight improvement were selected from various yoga techniques. The precautions we have to take, norms tha t we have to follow were taken care. So we developed this module, iintegrated yoga module for eyesight improvement. We started giving that in Yoga Camps.One week camp, 15 days camp, one month camp and we started documenting the result whether really it is useful or not. The results were very fascinating. When we have an average of 1000 or 1500 sstudents, we have found that the eyesight can improve by one Diapter for short sight sstudents with a practice of every day half an hour for one month. This iintegrated yoga module can bring such wonderful results. Practice for half an hour every day for one month, one Diaptor is going to reduce. Yoga in Education for Total Personality Development SERIES – 2 8 | Yoga for Eye Sight ImprovementWhen we continued children with -5, -6, -7 children were able to normalise their eyesight. Then we started taking up this. Initially we have short theory and then we go for the practice and what is the whole basis for the eyesight improvement that we are talking? Many people think that the accommodation power of the lens is going to change. No. It is Eye Ball Curvature. In short sight the image is falling too far in front of the Fovea. But why is that distortion taking place in the eye ball? This is because of the differential pull of the rectie muscles of the eye ball.So when we do yoga in which we handle the eye excercises to see that the muscles co-ordinate so cohesively that the eye ball starts becoming normal. How do we know it is going to become normal? One of our Opthalimic specialist Dr. Upadhyay in England, measured the eye ball curvature and after 15 days, after one month of yogic practices the eye ball curvature started getting normal. Such results prove that yoga brings in normalisation and it is these techniques that we have used. Trataka is the specialised practice that yoga prescribes. It is one of the six kriyas.Kriyas are essentially meant for clearnsing and to strengthen the nerves which connect the eyes to the brain which handles the different muscles and calming down of the mind, silencing of the mind, slowing down of the breath, does wonders. Therefore in this module we are going to use some Asanas, special breathing practices and mainly the Trataka and the meditation which help the people develop their eyesight. Yoga in Education for Total Personality Development SERIES – 2 Yoga for Eye Sight ImprovementLet us try to understand the structure and functions of the eye so that we can go ahead to understand how Yoga works in improving our eyesight. We all have two eyes. A resting eye is designed for distant vision. Near work always involve lot of work on the small, little muscles of the eye. Each eye is comparable to a pholographic camera. Just like the camera has a diaphragm and an aperture, our eye also has a dark highly pigmented diaphragm called Iris. This Iris cuts off all the light from entering into the eye ball and in the centre of the diaphragm is the little transparen' t hole called the Pupil.The diaphragm is called the Iris, the apercher is called the pupil. Through this pupil only nature allows the light to pass through. What are the functions of a good camera? It should have a very good powerful lens so that it can have a very clear image at its focal point and it should be able to adjust very perfectly to the light conditions and also to the distance of the object from the film of the Yoga in Education for Total Personality Development SERIES – 2 10 | Yoga for Eye Sight Improvement camera. Our eye although is comparable to a camera, is not having a shape of a camera.

What Is an Oxidant Definition of Chemistry Terms

An oxidant is a reactant that oxidizes or removes electrons from other reactants during a redox reaction. An oxidant may also be called an oxidizer or  oxidizing agent. When the oxidant includes oxygen, it may be called an oxygenation reagent or oxygen-atom transfer (OT) agent. How Oxidants Work An oxidant is a chemical species that removes one or more electrons from another reactant in a chemical reaction. In this context, any oxidizing agent in a redox reaction may be considered an oxidant. Here, the oxidant is the electron receptor, while the reducing agent is the electron donor. Some oxidants transfer electronegative atoms to a substrate. Usually, the electronegative atom is oxygen, but it can be another electronegative element or ion. Oxidant Examples While an oxidant technically doesnt require oxygen to remove electrons, most common oxidizers do contain the element. The halogens are an example of oxidants that dont contain oxygen. Oxidants participate in combustion, organic redox reactions, and more explosives. Examples of oxidants include: hydrogen peroxideozonenitric acidsulfuric acidoxygensodium perboratenitrous oxidepotassium nitratesodium bismuthatehypochlorite and household bleachhalogens such as Cl2 and F2 Oxidants As Dangerous Substances An oxidizing agent that can cause or aid combustion is considered a dangerous material. Not every oxidant is hazardous in this manner. For example, potassium dichromate is an oxidant, yet is not considered a dangerous substance in terms of transport. Oxidizing chemicals which are deemed hazardous are marked with a specific hazard symbol. The symbol features a ball and flames. Sources Connelly, N.G.; Geiger, W.E. (1996). Chemical Redox Agents for Organometallic Chemistry. Chemical Reviews. 96 (2): 877–910. doi:10.1021/cr940053xSmith, Michael B.; March, Jerry (2007). Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (6th ed.). New York: Wiley-Interscience. ISBN 978-0-471-72091-1.

5 Most Important Things You Can Do for the Environment

If you feel you’re not doing enough for the environment by replacing your incandescent light bulbs with LED lights and composting your kitchen scraps, maybe you’re ready to make a deeper commitment to environmental stewardship. Some of these strategies may seem a little radical, but they are among the most valuable actions you can take to protect and preserve Earth’s environment. Have Fewer Children—Or None Overpopulation is arguably the world’s most serious environmental problem because it exacerbates all of the others. The global population grew from 3 billion in 1959 to 6 billion in 1999, an increase of 100 percent in just 40 years. According to current projections, the world population will expand to 9 billion by 2040. This represents a slower growth rate than that of the last half of the 20th century, but it will nevertheless leave us with many more people to accommodate. Planet Earth is a closed system with limited resources—only so much fresh water and clean air and only so many acres of land for growing food. As the world population grows, our finite resources must stretch to serve more and more people. At some point, that will no longer be possible. Some scientists believe we have already passed that point. Ultimately, we need to reverse this growth trend by gradually bringing the human population of our planet back down to a more manageable size. This means more people must decide to have fewer children. This may sound pretty simple on the surface, but the drive to reproduce is fundamental in all species. The decision to limit or forgo the experience is a difficult one for many people because of emotional, cultural, and religious traditions and pressures. In many developing countries, large families can be a matter of survival. Parents often have as many children as possible to ensure that some will live to help with farming or other work and to care for the parents when they are old. For people in cultures like these, lower birth rates will only come after other serious issues such as poverty, hunger, poor sanitation, and freedom from disease have been adequately addressed. In addition to keeping your own family small, consider supporting programs that fight hunger and poverty, improve sanitation and hygiene, or promote education, family planning, and reproductive health in developing nations. Use Less Water—And Keep It Clean Fresh, clean water is essential to life—no one can live long without it—yet it is one of the scarcest and most endangered resources in our increasingly fragile biosphere. Water covers more than 70 percent of the Earth’s surface, but most of that is salt water. Freshwater supplies are much more limited and today a third of the world’s people lack access to clean drinking water. According to the United Nations, 95 percent of the cities worldwide still dump raw sewage into their water supplies. Not surprisingly, 80 percent of all illnesses in developing countries can be linked to unsanitary water. Especially if you live in a dry climate, you should use only as much water as you need, avoid wasting the water used, and strive to protect  water supplies. Eat Responsibly Eating locally grown food supports local farmers and merchants in your own community as well as reducing the amount of fuel, air pollution, and greenhouse gas emissions required to move the food you eat from the farm to your table. Eating organic meat and produce keeps pesticides and chemical fertilizers off your plate and out of rivers and streams. Eating responsibly also means eating less meat and fewer animal products such as eggs and dairy products, or perhaps none at all. Eating less meat is a matter of good stewardship of our finite resources. Farm animals emit methane, a potent greenhouse gas that contributes to global warming, and raising animals for food requires many times more land and water than growing food crops. Livestock now uses 30 percent of the planet’s land surface, including 33 percent of farmland worldwide, which is used to produce animal feed. Every time you sit down to a plant-based meal instead of an animal-based meal, you save about 280 gallons of water and protect anywhere from 12 to 50 square feet of land from deforestation, overgrazing, and pesticide and fertilizer pollution. Conserve Energy—And Switch to Renewable Energy Walk, bike, and use public transportation more. Drive less. Not only will you be healthier and help to preserve precious energy resources, but you’ll also save money. According to a study by the American Public Transportation Association, families that use public transportation can reduce their household expenses by $6,200 annually, more than the average U.S. household spends on food every year. There are dozens of other ways you can conserve energy. You can turn off lights and unplug appliances when they are not in use and substitute cold water for hot whenever practical. Other small steps you can take include weather stripping your doors and windows and not overheating or overcooling your home and office. (An added bonus is that a good office temperature also boosts productivity.) One way to start is to get a free energy audit from your local utility. Whenever possible, choose renewable energy over fossil fuels. For example, many municipal utilities now offer green energy alternatives so that you can get some or all of your electricity from wind, solar, or other renewable energy sources. Reduce Your Carbon Footprint Many human activities—from using coal-fired power plants to generate electricity to driving gasoline-powered vehicles—cause greenhouse gas emissions that heat the atmosphere and contribute to climate change. Scientists are already seeing significant climate changes that point to the likelihood of serious consequences. Some scenarios foresee increasing drought that could further reduce food and water supplies and, at the same time, rising sea levels that will submerge islands and coastal regions and create millions of environmental refugees. Online calculators can help you measure and reduce your personal carbon footprint, but climate change is a global problem that requires global solutions and, so far, the world’s nations have been slow to find common ground on this issue. In addition to lowering your own carbon footprint, let your government officials know that you expect them to take action on this issue—and keep the pressure on until they do. Edited by Frederic Beaudry