Microorganisms form part of our normal flora, however they can become pathogens where their main role is to survive and multiply, often at the expense of the host. Pathogens cause infectious diseases depending on their virulence; this was first realised when Louis Pasteur discovered microbes contaminated wine, causing it to go sour. He wondered how microbes affected humans; however it was Robert Koch that linked the contamination of microbes to the cause of infectious diseases. Between them they discovered and identified many of the microbes that caused diseases. Bacteria, Fungi, Virus and protozoan are all agents that cause infectious diseases. Infectious diseases can be asymptomatic for a long period of time before symptoms are apparent, …show more content…
Once infected, B.burgdorferi affects the lymphatic system, and if left untreated damages the joints and nervous systems. Other factors include poor population health causing contaminated food sources or water supplies, and finally increase in international travel as these increases the emergence of pathogens to new environments.
‘Numerically, RNA viruses dominate 37% of all emerging and re-emerging pathogens’ (Woolhouse and Gowtage-Sequeria, 2005:1845). Human Immunodeficiency Virus: HIV, was first isolated in 1983 and is a rapidly emerging pathogen that has affected medicine, HIV is the most research aspect of medicine ever since it was discovered. HIV can progress to Acquired Immunodeficiency Syndrome (AIDS); where the immune system cannot fight off opportunistic diseases that then become life-threatening, however not in all cases of HIV infection progresses to AIDS. HIV is transmitted in body fluids and the main way of transmission is by sexual contact; once infected, HIV: made up of eight genes, uses CD4 cells to make copies of itself destroying the cells in the process, leading to reduced CD4 counts. Another emerging pathogen is H5N1 (influenza A), which was isolated in humans in 1997 ‘emerged from wild birds to cause epizootics that amplified virus transmission in domestic poultry’ (Morens and Fauci, 2013). Avian influenza (Al) is an infectious viral disease of birds, ‘Al viruses are divided into two groups based on their virulence:
Bacterial and fungi infections are easy to cure with the use of antibiotics, where as viruses can be hard to cure or vaccinate against, such as the common cold. Bacteria can be found everywhere and anywhere Soil, Water, Plants, Animals, material and even deep in the earth's crust. Bacteria feed themselves by making there food with the use of sunlight and water. We would not be able to live without Bacteria. The human body consists of lots of friendly bacteria which also protect us from dangerous ones by occupying places in the body. Some of the most deadly diseases and devastating epidemics in human history have
For many years the identification of microorganisms has been important in the world of medicine. It is essential or correct disease diagnosis in patients and for proper treatment. Knowing the correct identity and characteristics of microorganism is crucial when disease outbreaks occur in populations, also knowing how humans can benefit from microorganisms is important; many can be used in making certain foods or antibiotics.
In this assignment I am going to explain how infections are caused by, bacteria, viruses, fungi and parasites. I will then explain how pathogenic microorganisms grow and spread.
Common sources of infection include food, water, sick people (colds and flu or winter vomiting virus), animals and poor housing
Food production led to the causes of many things, some such as germs carried by farmers usually, technology, and literacy. Infections and diseases were led by various animals, being around them or being involved with them caused this. Some of the major diseases we get as humans are smallpox, tuberculosis, flu, plague, measles, malaria, and cholera. These are evolved and mainly gotten from animals, usually animals like house pets or farm animals, since humans interact with them more than other kinds of animals. Germs and microbes pass through victims and spread around fairly simple or not simple at all. Usually, the easiest way for a germ to spread is through waiting to be passed to another victim. As if someone who is “sick” is contagious and
Based on research and observation, we now know that infectious diseases are caused by microorganisms (pathogens) and that the immune system provides defense against infectious diseases.
The exact mechanisms for its pathology are still trying to be understood. Although according to the Center for Disease Control, Lyme disease caused by B. burgdorferi has become the most common bacterial disease in the world.
Communicable diseases have always created a host of serious of problems. These diseases cause physical, emotional, and even financial problems in our societies today. Communicable disease is a sickness that is passed on through the transmission of infectious illnesses. People, food, animals or water can pass many infections from humans to humans or animals to humans. Humans can pass infectious diseases to each other from touching or exchanging body fluids. In 1981, the human immunodeficiency virus (HIV) marked the official start of the HIV epidemic which became one of the world’s most deadly communicable diseases (Kaiser Family Foundation, 2015). The widespread of the human immunodeficiency virus has affected approximately 1.2 million people in the United States, and roughly 35 million worldwide is living with HIV (Centers for Disease Control and Prevention, 2015).
Influenza A viruses, which have been isolated from a wide variety of avian and mammalian species, including pigs, horses, mink, wild birds and humans are the common pathogens with high variability that cause acute respiratory disease (Lin et al., 2007). They are responsible for both seasonal influenza outbreaks and occasional pandemics affecting millions of people worldwide. Besides, they are divided into two groups, highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI). Mortality of HPAI may be as high as 100% whereas LPAI causing milder symptoms (Metreveli, 2006). Furthermore, they are classified into subtypes based on the antigenic differences of the surface glycoproteins, hemagglutinin (HA) and neuraminidase
To start, Ebola and HIV are both zoonotic RNA viruses that underwent evolution and mutation to emerge from the jungle and morph into the deadly diseases they are today. It is thought that Ebola originated in Africa fruit bats, and was transmitted to humans for the first time through contact with bodily fluids from the bats, either as blood or saliva. Transmission to humans most often occurs through hunting and preparation of infected bushmeat, or consumption of fruit contaminated with bat saliva. This was made possible because of human encroachment on natural areas and bat habitats (Alexander, 2015). Once present in the human population more hosts allowed for extensive mutation. This is because RNA viruses use RNA
HIV is a quite detrimental virus that has caused much disruption during the 1980’s when it came to life. HIV is “one of the fastest evolving of all organisms” (Rambaut A. ET. Al. 2004) HIV has found ways in which to resist drugs and shows evolutionary mechanisms. The HIV virus has also
As already mentioned, the H5.N1 is a subtype of an influenza A type. This type consists of RNA. This RNA names as HA and NA. The HA is glycoproteins found on the surface of the virus. This special protein helps the virus to bind to the host cell. While NA is glycosylated enzyme sits on the surface as well. It helps to release the virus from the host cell. In reality, the least pathogenic virus is H5.N1 or (LPAI H5N1), is commonly happening in wild birds for example, in 1983 it is reported that the virus being carried by the ring-billed gulls in Pennsylvania, ( Bird flu (H5.N1) Genetic in news-medical). The virus itself cannot be pathogenic unless some changes occur, which means new progeny. When the RNA of two viruses enters a combination process in the host cell.
Advancements in our modern world are often viewed in a positive light; however, this growth and development can have a dark side to it – further brought out in devastating medical outbreaks such as pandemics. A pandemic is a global epidemic affecting an exceptionally high portion of the population, further highlighted through human fear and stigma surrounding these infectious diseases (Downs, 2005). Roughly three of every four emerging infectious diseases are zoonotic diseases, both Ebola and HIV fall into this category (Wolfe et al., 2005). HIV is believed to have originated from a species of chimpanzees in west equatorial Africa, and exposed to humans through contact with infectious blood while hunting. The first reported case was in
The year of 1959 saw the first case of the sexually transmitted immune eating disease HIV .Human Immunodeficncy Virus or HIV was tested positive in a man from Congo. HIV is the attack by a disease of the body’s immune system essentially decaying it over time. With the simple symptoms of the common influenza HIV is a silent killer with more than 70 million infections globally and more than 35 million deaths (World Health Organisation, 2015). HIV can be transmitted in many different ways, as well as having multiple symptoms and signs. There is no current cure for HIV or AIDS but there are multiple biological options being made available. HIV destroys the immune system atrociously, allowing for the body to become weak and contract other diseases, most commonly AIDS (Acquired Immune Deficiency Syndrome) HIV and AIDS is one of the world’s mortiferous disease and has a world of biological beauty and intelligence behind it.
Health care professionals within conventional medicine believe that diseases are caused by microorganisms such as bacteria and viruses.