The H1N1 Influenza Virus

According to Center for Disease Control (CDC), influenza viruses are divided into three types, designated as A, B, and C. Influenza type C usually only causes either very mild symptoms or no symptoms at all. Types A and B, however, are responsible for epidemics of respiratory illnesses that can result in hospitalization, or even death. Influenza is constantly changing over time by mutations. This continual change allows the virus to evade the antibodies that were meant to kill it. A host infected with influenza virus develops antibodies against that virus; as the virus changes, the "first" antibody no longer recognizes the "newer" virus and infection can occur because the host does not recognize the new flu virus as a problem until the infection is well under way. The first antibody developed may, in some instances, provide partial protection against infection with a new influenza virus. According to Medicine Net.com, In 2009, almost all individuals had no antibodies that could recognize the novel H1N1 virus immediately. It quickly spread throughout the world so fast that the WHO declared this new flu strain (termed novel H1N1 influenza A swine flu). There are currently four main strains of influenza circulating worldwide. Three of the viruses are type A, and one is type B. Type A viruses are divided into subtypes based on the differences in two viral proteins called hemagglutinin (H) and neuraminidase (N). The three subtypes of influenza A are A(H1N1), A(H3N2), and A(H5N1). The reason for several strands of type A are because of the two kinds of change influenza A

They view proteins created by infected cells, and are sent to other cells to start them making protective substances. Influenza, commonly known as the flu, is a very contagious disease caused by a virus infecting many part of our bodies including the reparatory tract. The influenza virus depending on the sternness usually includes: fever, cough, sore throat, headache, stuffy and running nose, muscle soreness and fatigue. It also can include vomiting, diarrhea, and nausea.

Every year, millions of people start talking about the influenza virus and getting their vaccines as the flu season approaches, which starts around the October-November period and reaches its peak between December and March. Therefore, public health officials around the world- and in the U.S in particular- are constantly challenged by properly preparing for the annual influenza dilemma, given that this viruses, and other respiratory viruses, are a serious health threat to the U.S population and the world as a whole. Furthermore, what makes the influenza virus even more challenging to control is that it can mutate rapidly and reassort to form new strains, having the ability to reside in multiple animal hosts. In fact, many scientists and researchers have been doing in-depth intensive research so as to understand the mechanism behind this unique characteristic of the virus, try to find new ways to control it, and explore different areas of protection and vaccination.

The Great Influenza is a book not many enjoy. However, Dr. Petri enjoys this book for reasons that are lost to many. The book starts off on part one chapter 1 the Warriors. it starts off with imagery of September 12, 1876 talking about it crowd in an auditorium in Baltimore’s Academy of music. this was too launch John Hopkins University where they say they would change all of American education and in this first page you meet Thomas H. Huxley an English scientist who is the keynote speaker of this event. then give me George Armstrong Custer who “led the seventh Cavalry to with the stretching at the hands of him video savages resisting encroachment of the white man.” customer had spoke on the front page of the Washington star. then the book starts going deeper into detail

Influenza is not a deadly virus and does have a vaccination. One of the three types of influenza, type C, “type C infections cause a mild respiratory illness and are not thought to cause epidemics” (Types of Influenza Viruses). The other two types of influenza viruses type“ A and B viruses cause seasonal epidemics” and happen mostly when winter hits (Types of Influenza

There are there types of influenza A and C or the most severe types and B which is the most common, Luckily not the to severe. The virus works by first attaching to the outside of a host cell. It injects its RNA into the cell. Unfortunately our cells treat the RNA like they should. It translates the viral genes using the cell’s ribosomes and enzymes. Now the virus can take the cell over and use it to reproduce more viruses. Sooner or later it releases the new nauseating viruses and they search for another cell to raid.

Describe two innate (nonspecific) immune responses that might prevent an influenza virus from causing any noticeable infection, even if the virus enters your respiratory passages.

Influenza is caused by an RNA virus from the Orthomyxoviridae family (that consists of the genera influenza A, B, and C). Human influenza A and B viruses cause seasonal epidemics almost each winter within the United States. Influenza type B infects humans only, therefore it is unable of undergoing a mutation. Pandemics are caused solely by influenza A strains. The emergence of a new and completely different influenza virus to infect people will cause an influenza pandemic. Influenza kind C infections cause a mild respiratory illness and aren't thought to cause epidemics (Duncan, 2013).

Someone may sneeze or cough and not cover their mouths and another person may come along and inhale those water droplets left behind by the infected person, which will cause them to become infected. Another common route of transmission is when an infected person sneezes or coughs into their hand and touches a surface. A healthy person may then come along and touch the surface then their face, nose, mouth or eyes and then become infected with the influenza. The H1N1’s route of entry and exit is through the mouth and nose. The primary target for this H1N1 virus is the upper respiratory tract in humans. This virus spreads even more quickly among crowded places as well as being able to survive longer outside of the body in cold and dry environments. This specific influenza virus reproduces by the lytic cycle. Once the H1N1 virus has entered the body, it supplements its own DNA/RNA into the body’s cells. This instructs the cell to stop its normal functioning for the body and begin manufacturing the H1N1 virus. This non-living organism “hijacks” our bodies to supply the raw materials it needs to replicate and infect our bodies. Once the infected body cell makes enough viruses, it splits open or lyses resulting in the death of that cell and those new virus particles repeat the cycle, cell after cell until our body begins to fight back which is when we begin to feel the symptoms of the

I think many can testify to being guilty of brushing off symptoms like a stuffy nose, and the feeling of fatigue as the common cold, treatable by over the counter drugs. We tend to ignore these minor signs of what could possibly be a very dangerous and severe viral infection, this respiratory infection being the influenza virus. Flu activity most often appears between the months of February and May, leading many to believe their symptoms might be caused by allergies. Although symptoms are very similar, the flu can cause epidemics with the deadly outcomes, as the common cold is just a nuisance for us.

Influenza strikes this country in pandemic proportions every year. Although there are many factors contributing to morbidity and mortality, the mortality rate varies from year to year. According to the Centers for Disease Control and Prevention, in the thirty year range from 1976 to 2006, saw death rates from a low of 3000 to a high of 49000 (Centers for Disease Control and Prevention, 2016). So far this season, there have been 3697 deaths from influenza related illness (CDC, 2016). In 2009, the virulent H1N1 strain, with a 20% risk of death, also brought the difficulties of lack of research based clinical evidence for treatments (Cook, et al., 2010). The lack of research conducted during pandemics stems from the delay caused by the often

There are two important proteins used in the determination of the type of influenza; haemagglutinin (HA) and neuraminidase (NA). There are 18 known variations of the haemagglutinin protein and 11 of the neuraminidase protein, giving hundreds of possible variations in the subtypes of the virus . These subtypes are further divided into different strains that have a divergent molecular makeup, giving rise to viruses that differ in virulence, ease of transmission and severity of symptoms. Not all strains of influenza can cause disease in humans; influenza D subtypes cannot infect humans and influenza C infections are rare and usually very minor. Influenza A and B are the subtypes that are responsible for the common infections and the epidemics and pandemics that occur periodically, with influenza A causing the majority of these infections. The virus is transmitted through the inhalation of droplets which are expelled when an infected person coughs or sneezes, through contact with a contaminated surface and through the exchange of saliva . The infected person becomes infectious to others around 12 hours after first contact with the virus and remains contagious for around the next five days; this can vary as the immunocompromised can take longer to subdue the virus and children tend to be more infectious than adults . The virus incubates in the respiratory tract by invading cells through the cleavage of the viral protein haemagglutinin by human proteases . The pathogenicity of a certain strain is determined by the spread of proteases in the respiratory tract that can cleave the proteins of the virus; a strain is typically milder if the proteases that reside in the lungs and throat are the only ones capable of cleaving the virus, causing an upper respiratory tract (URT)

Around 5 million people worldwide are affected annually by the influenza A virus (IAV), with infection resulting in severe morbidity and sometimes death. Although effective IAV vaccines exist, annual influenza epidemics occur due to its ability to quickly evolve new strains. Therefore, IAV remains a serious public health threat as evidenced by the recent pandemics involving swine H1N1 and avian H7N9. Thus, there is a vital need to develop more effective vaccines against influenza. Normally, vaccines function by priming the immune system to recognize a pathogen so that the body can more easily identify and eliminate it upon a second encounter. This protective immunity relies on receptors in the innate immune system such as the pattern recognition receptors (PRRs) Toll-like receptors (TLRs) and retinoic acid inducible gene I (RIG-I). In contrast, Nod-like receptors (NLRs) sense cellular damage as a result of infection and engage the inflammasome. Inflammasomes are multiprotein complexes that stimulate the secretion of inflammatory cytokines. Recent work by Pang et al. examined the relevance of host recognition of viral PAMPs versus virus-inflicted damage in linking innate recognition of IAV to adaptive immunity. Mediation of adaptive immunity to IAV is attributed to production of interleukin-1α (IL-1α) and IL-1β, cleavage products of the inflammatory cytokine IL-1. Pang et al. provided evidence that induction of an adaptive CD8+ T cell response did not depend on PRRs

With a huge number of victims, 80 to 100 million, since 1918, the influenza is considered as one of the most pandemic diseases ever. There are three types of influenza virus: influenza virus A, influenza virus B, and influenza virus c. These are a subtypes of the virus family orthomyx-oviride. The types B and C do not cause pandemic diseases while type A does. The type A classified into three main subtype H1.N1, H1.N2, and H3.N2. The (H.N) refers to the two kinds of proteins on the surface of the virus (hemagglutinin and neuraminidase). The difference in numbers is due to the difference in protein variability. A H1.N1 virus which is widely known as Spanish flu is the only type that can transmit from human to human. The H5.N1, or “bird flu”

################################################# Part 2 ################################### 　　　There are multiple different sources for epidemiological measures used for tracking and reporting the number of cases. There are websites where you can go to post confirmed cases in areas, where that information is then taken and calculated. There are also places that provide charts for the amount of confirmed outbreaks and then separates them from human cases and avian cases. But the best types of reports available are the map tracking ones. Where they give distinction marks for avian and human cases and all over the different areas of the world. This is very handy for seeing how bad and large an outbreak is and what species is affected, whether it is humans or birds.