The human body contains countless amount of defense from the ever so present dangerous pathogens found in its surroundings. If any of these pathogens is successful in entering the body, the body must them perform a series of responses in order to kill or eradicate the issue.
Such a situation would be the influenza virus. The influenza A and B viruses are made of eight single-stranded viral RNA segments. When entering the body, this virus attaches itself the cell through the recognition of the sialic acid of the host cell. After this, it will inject its RNA into the cell, and targets proteins that would reject the virus, thus rendering the cell to its genetic code, and making this cell reproduce the viral code instead of the original hosts
Orthopoxvirus variola is the virus responsible for the well-known smallpox disease. It belongs to the Poxviridae family which is further split into the subfamilies Entomopoxivirinae which only affects insects, and Chordopoxivirinae which infects vertebrae (Hughes). It is in group one of the Baltimore Classification since it possesses double-stranded DNA. This group also includes viruses in the Herpesviridae family, certain bacteriophages, as well as the mimivirus. The linear genome consists of approximately 186 kb pair and, like all orthopoxviruses, is about 200 nm in diameter (Li; Riedel). Virus particles may be enveloped, but the majority will be nonenveloped when released from a lysed cell, ready and capable to affect another. Extracellular enveloped viruses evolve from their precursors intracellular enveloped virus and cell-associated enveloped virus and contain proteins that aid the virus in neutralizing host cell antibodies to enhance virus spread (Smith). Entrance into the host cell may be accomplished by fusion of endocytosis, contingent on the particular strain. Host cell cytoplasm is the site of poxvirus replication, therefore host nuclear enzymes are unavailable to the virus; to overcome this, DNA-dependent RNA polymerase enters the host with the virus (Hughes).
The objective of the host is to "escape" from the pathogen. This can be done through the use of the immune system or by quickly dying. When a host dies with the pathogen still inside, the pathogen dies as well. Resistance to invaders evolved as a result of the development of the mechanism of immunity. The development of immunity depends on the recognition of differences in chemical structures of substances.
The human immune system is an amazing system that is constantly on the alert protecting us from
The job of the immune system is to keep “foreign” invaders out of the body, or if one gets in, to seek it out and kill it. These foreign invaders are called pathogens, which are tiny organisms that can cause an infection in the body. Pathogens can be bacteria, parasites, and fungi (http://www.niaid.nih.gov/topics/immuneSystem/pages/whatisimmunesystem.aspx).
The immune system acts as a defense system against unwanted microbes and pathogens in a healthy human being. It prevents them from entering the body, or if they have already entered the body, it stops them from doing harm to the body. The three main tasks of the immune system are neutralizing pathogens that have entered the body and then remove them, recognizing and removing harmful substances from the body, and fighting against its body’s cells that have been altered due to an illness (PubMed Health).
Fig. 1. Fine epitope mapping of anti-H5 2A-scFvFc antibody. A. Flow cytometry profiles for immunoreactivity of single-clone HA1-M mutants displayed on the surface of yeast. Single point mutations that abolish yeast surface binding of anti-H5 2AscFvFc were analyzed and mapped to distinct regions of HA1. B. Schematic representation of the epitopes recognized by anti-H5 2AFc to HA1 on the yeast surface. Amino acid positions are designated in H5 numbering. A linear epitopes (aa 206-211) recognized by 2AFc is colored in red. The regions encompassing the receptor-binding domain are colored in cyan.
Influenza, or the "flu," is an infection that is caused by the influenza virus. It is a virus that generally infects the olfactory organ, pharynx, and it can sometimes spread to the lungs (2007). Symptoms of influenza can be identified as acute fever, cough, chills, fatigue, body aching and, in young children, ear aches. Unlike the viruses that cause the common cold, the influenza virus can cause severe illnesses like pneumonia, especially in those who are very young or very old, or who have conditions such as cancer, heart disease, bronchial asthma and diabetes. Influenza can be spread by something as simple as an infected individual coughing or sneezing, through little droplets that go up to a meter (3 feet) and land on any nearby individuals
One thing that must be noted is that contrary to popular belief, infectious agents such as viruses, bacteria, parasites, etc. are not desig...
Hepatitis B virus (HBV) is a severe and common virus that has infected ‘more than two billion people alive today at some point in their life.’1 It is a hepadanavirus that interferes with the liver functions as it replicates in the hepatocytes (liver cells) and induces a immune response that is responsible for the inflammation of liver.2 Viruses are not motile, which means that HBV is also sessile and does not form spores. The spherical virion, is called a Dane Particle3 that is 42nm in diameter binds to the surface of hepatocyte.1 The virion itself contains an inner protein core, 27nm thick filled with circular partially double stranded DNA, DNA polymerase and reverse transcriptase.1 It is an enveloped virus, so it also holds an outer lipoprotein envelope4 that is 7nm thick and is comprised of many embedded surface proteins such as surface antigen for viral binding and entry.1 HBV has an average incubation period of three months, which means that it does not start showing symptoms for the first three months that the person is infected and that person can unknowingly infect others.2 ...
Throughout 1918 and 1919, influenza spread quickly in three waves killing an estimated 50 million to 100 million people worldwide. With the best-recorded first case having occurred in Fort Riley, the contagious flu spread across military camps around the United States. Due to the world war, the influenza virus was brought over to Europe where it infected people in nearly every country. This disease would end up causing one of the greatest pandemics in human history, but would also catalyze great advancements in science and medicine.
The influenza pandemic of 1918-1919 killed more people than the Great War, known today as World War I (WWI), at somewhere between twenty and forty million people. (1) Influenza is a virus that appeared in 1918 and caused a pandemic. It made an enormous impact that is still significant to the world today. It has pushed scientists to make advancements in the medicine and vaccination industry that continue to grow each and every day. Influenza may be a horrible thing, but without it we wouldn’t be where we are today.
The immune system has the important job of protecting the body from foreign invaders. It is made up of a network of cells (including white blood cells), tissue and organs. The foreign invaders the immune system fight include viruses, bacteria, microbes and pathogens. In order to stop these foreign invaders, there is a process known as immune response that attacks in three different lines of defence. Without this immune response, the body would be constantly under invasion by pathogens trying to attack and induce illness.
Influenza or flu is caused by RNA viruses of the family orthomyxoviridae, that affects the nose, throat, and lungs- the respiratory system. The common symptoms are: fever and respiratory problems, such as cough, sore throat,stuffy nose, as well as headaches and muscle aches. Influenza viruses are spread mainly by droplets made from people coughing, sneezing or talking while having the flu. These droplets can land in the mouths or noses of people or can inhaled into the lungs. It is least common for the virus to spread by touching an infected surface then their mouth or nose. Flu viruses are divided into 3 categories, A, B, C. A and B are responsible for problems in the respiratory system that typically occurs during the winter. Influenza types C is quite different from A and B. Type C only cause mild respiratory symptom or none at all.
Preventing serious infections by making a person immune to the infection is called immunization. This process is usually performed by the administration of a vaccine to stimulate the person’s immune system to protect them against a subsequent infection or disease. According to the World Health Organization (2016), more than 5 million deaths were prevented annually between 2010 and 2015 due to vaccinations that were used around the world. Vaccines work with the natural ability of the human immune system to develop immunity to fight disease. When a foreign infectious pathogen such as bacteria or a virus enters the body, it multiplies and becomes an infection and in many cases, this infection leads to an illness. To understand how vaccines
In 1918-19 approximately 50 million deaths were a detriment of the Spanish H1N1 virus pandemic; a respiratory virus. According to the World Health Organization, the second Influenza A H1N1 pandemic in 2009 spread to more than 200 countries causing more than 18 000 deaths. Before the World Health Organization had announced the official end of the pandemic in August 2010, in July 2009 the World Health Organization sent out a phase 6 warning that H1N1 could soon be a global pandemic. It is important to recognize that the 2 different outbreaks had different A/H1N1strains effecting the world population; this suggests A/H1N1has a high ability for mutation, severely complicating the human body’s natural immune mechanism of antigenic drift. (Qi-Shi Du et al., 2010)