Treppo Carnico
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Treppo Carnico là một đô thị ở tỉnh Udine trong vùng Friuli-Venezia Giulia thuộc Ý, có cự ly khoảng 120 km về phía tây bắc của Trieste và khoảng 50 km về phía tây bắc của Udine. Tại thời điểm ngày 31 tháng 12 năm 2004, đô thị này có dân số 652 người và diện tích là 18,7 km².[1]
Treppo Carnico giáp các đô thị: Arta Terme, Ligosullo, Paluzza, Paularo.
Vaccinology is the science or method of vaccine development. Over 200 years ago, English physician Edward Jenner observed that milk- maids who contracted a mild viral disease called cowpox were rarely victims of a similar but deadly disease called smallpox. This observation led Jenner to infect a healthy young boy with cowpox, and six weeks later challenge the boy with fluid from a smallpox pustule. The boy remained free of smallpox, and the era of vaccinology began. The foundation that Jenner laid began a course of vaccine development that would lead to the eradication of smallpox and polio, and vaccines for a spectrum of human pathogens that include influenza, bacterial pneumonia, whooping cough, rubella, rabies, meningitis, and hepatitis B.
The term “vaccine” is derived from the Latin word “vaccinus” whichmeans “pertaining to cows” – a reflection on Jenner’s pioneering studies using cowpox vaccinia virus to prevent human smallpox (variola). Vaccines take advantage of using relatively harmless foreign agents to evoke protective immunity that resists infection and/or disease pathogenesis. There are many different types of vaccines including attenuated microbes, inactivated microbes, inactivated toxins, and purified proteins or polysaccharides derived from human pathogens. Some examples include attenuated measles, mumps, and rubella (MMR) vaccine routinely administered to infants, inactivated influenza vaccine, inactivated tetanus toxoid vaccine, and purified hepatitis B virus protein antigen vaccine. Vaccines provide acquired immunity to pathogens and are generally used to prevent disease rather than cure it. There are a variety of vaccine strategies that may be commonly used in the future including DNA vaccines, skin patch vaccines, and edible vaccines.
Despite the ability to vaccinate people and animals for protection against several important pathogens, the majority of people and food or companion animals worldwide are still plagued by known and emerging infectious diseases. Emerging or re-emerging infectious diseases continually threaten human health and impact global se-curity by affecting food for an increasing world population, access to international trade and economic growth, and raise concerns for potential use as pathogens in bioterrorism. The majority of emerging infectious diseases are of zoonotic origin, i.e. transmissible between humans and animals causing infection in both species. For example, in the past 10 years the world has had to respond to SARS-associated coronavirus identified in some domestic and wildlife species, Nipah virus from bats via pigs, influenza viruses from birds, and the West Nile virus from birds via mosquitoes. In addition, naturally occurring zoonotic diseases such as anthrax and antimicrobial-resistant organisms have emerged in part as a result of the agricultural practices that include use of antimicrobials for disease prevention and growth promotion of several domesticated species. Finally, the U.S. and foot and mouth disease.
There are a number of factors that affect emerging infectious disease including (1) introduction of infection into new host populations, e.g. bovine spongiform encephalitis; (2) establishment and further dissemination within new host population, e.g. ecological factors favoring vectors or reservoir hosts; (3) agricultural or economical development, e.g. dams (shistosomiasis) or deforestation (malaria); (4) human demographics and behavior, e.g. population growth, international travel, drug use; and (5) microbial adaptation, e.g. antibiotic resistance (tuberculosis). Unfortunately, the capacity to address emergence or re-emergence of infectious diseases is limited in part by (1) lack of efficacious vaccines or therapeutic treatment modalities; (2) limited support for and deterioration of surveillance of vector-borne and zoonotic diseases; (3) erosion in the number of scientists, public health investigators, and particularly veterinarians who are educated in relevant fields that include medical entomology, vector ecology, epidemiology, tropical medicine, and microbiology of zoonotic pathogens; (4) limited tools to address emergence of drug resistant pathogens and arthropod vectors; and (5) limited biosafety facilities, e.g. BSL3 and BSL4, that can contain the pathogens and animal models need for study.
To effectively prevent and control known and emerging infectious diseases, the scientific and health communities need to develop a discovery to control continuum. It is imperative that those in human, animal, agricultural and environmental sciences work together to address threats associated with infectious diseases. Basic research and a greater understanding of disease epidemiology can lead to improved diagnostics and vaccine strategies to control infectious diseases; however, veterinary medicine must bridge the gap between recognizing zoonotic diseases and preventing transmission among animal and human populations. To achieve these goals, the veterinary medical mission must be closely aligned with training students and professionals in relevant fields, and in advanced technologies to combat zoonotic and animal infectious diseases.
The development of effective vaccines represents one of the most promising approaches for providing cost-effective interventions against zoonotic and animal infectious diseases. Animal models have contributed to the considerable progress in our understanding of the mechanisms of immunity and disease pathogenesis associated with infectious agents by providing identification of vaccine candidate antigens, and in demonstrating proof-of-principle vaccine strategies. It is clear that vaccines can be an effective strategy to control infectious diseases, and clearer that veterinary medicine is at the interface between animal and human health. Types of vaccine There are several types of vaccines in use. These represent different strategies used to try to reduce risk of illness, while retaining the ability to induce a beneficial immune response. Killed Some vaccines contain killed, but previously virulent, micro-organisms that have been destroyed with chemicals, heat, radioactivity or antibiotics. Examples are the influenza vaccine, cholera vaccine, bubonic plague vaccine, polio vaccine, hepatitis A vaccine, and rabies vaccine. Attenuated Some vaccines contain live, attenuated microorganisms. Many of these are live viruses that have been cultivated under conditions that disable their virulent properties, or which use closely related but less dangerous organisms to produce a broad immune response; however, some are bacterial in nature. They typically provoke more durable immunological responses and are the preferred type for healthy adults. Examples include the viral diseases yellow fever, measles, rubella, and mumps and the bacterial disease typhoid. The live Mycobacterium tuberculosis vaccine developed by Calmette and Guérin is not made of a contagious strain, but contains a virulently modified strain called "BCG" used to elicit an immune response to the vaccine. The live attenuated vaccine containing strain Yersinia pestis EV is used for plague immunization. Toxoid Toxoid vaccines are made from inactivated toxic compounds that cause illness rather than the micro-organism. Examples of toxoid-based vaccines include tetanus and diphtheria. Toxoid vaccines are known for their efficacy. Not all toxoids are for micro-organisms; for example, Crotalus atrox toxoid is used to vaccinate dogs against rattlesnake bites. Subunit Protein subunit – rather than introducing an inactivated or attenuated micro-organism to an immune system (which would constitute a "whole-agent" vaccine), a fragment of it can create an immune response. Examples include the subunit vaccine against Hepatitis B virus that is composed of only the surface proteins of the virus (previously extracted from the blood serum of chronically infected patients, but now produced by recombination of the viral genes into yeast), the virus-like particle (VLP) vaccine against human papillomavirus (HPV) that is composed of the viral major capsid protein, and the hemagglutinin and neuraminidase subunits of the influenza virus. Subunit vaccine is being used for plague immunization. Conjugate Conjugate – certain bacteria have polysaccharide outer coats that are poorly immunogenic. By linking these outer coats to proteins (e.g. toxins), the immune system can be led to recognize the polysaccharide as if it were a protein antigen. This approach is used in the Haemophilus influenzae type B vaccine. Effectiveness Vaccines do not guarantee complete protection from a disease. ometimes, this is because the host's immune system simply does not respond adequately or at all. This may be due to a lowered immunity in general (diabetes, steroid use, HIV infection, age) or because the host's immune system does not have a B cell capable of generating antibodies to that antigen. Even if the host develops antibodies, the human immune system is not perfect and in any case the immune system might still not be able to defeat the infection immediately. In this case, the infection will be less severe and heal faster. Adjuvants are typically used to boost immune response. Most often aluminium adjuvants are used, but adjuvants like squalene are also used in some vaccines and more vaccines with squalene and phosphate adjuvants are being tested. Larger doses are used in some cases for older people (50–75 years and up), whose immune response to a given vaccine is not as strong. The efficacy or performance of the vaccine is dependent on a number of factors: • the disease itself (for some diseases vaccination performs better than for other diseases) • the strain of vaccine (some vaccinations are for different strains of the disease) • whether one kept to the timetable for the vaccinations • some individuals are "non-responders" to certain vaccines, meaning that they do not generate antibodies even after being vaccinated correctly • other factors such as ethnicity, age, or genetic predisposition. When a vaccinated individual does develop the disease vaccinated against, the disease is likely to be milder than without vaccination. The following are important considerations in the effectiveness of a vaccination program: 1. careful modelling to anticipate the impact that an immunization campaign will have on the epidemiology of the disease in the medium to long term 2. ongoing surveillance for the relevant disease following introduction of a new vaccine and 3. maintaining high immunization rates, even when a disease has become rare. In 1958 there were 763,094 cases of measles and 552 deaths in the United States. With the help of new vaccines, the number of cases dropped to fewer than 150 per year (median of 56). In early 2008, there were 64 suspected cases of measles. 54 out of 64 infections were associated with importation from another country, although only 13% were actually acquired outside of the United States; 63 of these 64 individuals either had never been vaccinated against measles, or were uncertain whether they had been vaccinated.