The H9N2 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

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.

According to the CDC there was a breakout in “1918-19 Flu pandemic, which killed as many as 50 million people worldwide”causing the biggest breakout for Influenza (Reconstruction of 1918 Influenza Pandemic Virus). Influenza originated from Asia and the Middle East. Virtually all mammalian species have influenza. Influenza is a contagious respiratory illness caused by the Influenza virus. There are three types of Influenza: type A, type B, and type C. Influenza has numerous symptoms, vaccinations, and is unlikely to kill it’s host.

According to the Centers for Disease Control and Prevention (CDC, 2013) national healthcare disparities report for 2010, influenza and pneumonia are ranked within the top ten major causes of death in the United States. The influenza viruses that will be discussed throughout this case study include the human influenza viruses: A and B. These viruses are responsible for seasonal epidemics during the fall and winter around the globe in temperate environments. Historically influenza outbreaks have had a seasonal distribution and characteristic time course although according to the CDC (2017) factors influencing the extent and severity of an outbreak are less clear. Generally, there are two or three different influenza strains typically circulating concurrently in any given

Influenza remains as a significant global threat to public health. In United States alone, a typical influenza epidemic results in over 25 million infections, 300,000 hospitalizations and 13,000 deaths every year (1). The virus evolves antigenically from one year to the next, requiring annual reformulation of the vaccine and leading to variable vaccine efficacy. Exacerbating this natural antigenic evolution, adaptation to the chicken eggs may occur during the manufacture of virus used to produce the inactivated vaccine (2). This year such adaptation has reduced the vaccine efficacy against H3N2 strain (3). Low vaccine efficacy is expected to generate higher attack rates, as has already occured in Australia (3, 4). Compounding the effects of low vaccine efficacy, public perception following the widespread media attention may depress vaccine uptake for a given year. The combination of low vaccine efficacy and low coverage has the potential to reduce herd immunity, putting the population at risk of elevated infection incidence and ultimately high rates of infections and mortality. Consequently, optimizing epidemiological effectiveness of vaccination given vaccine efficacy is imperative to minimize the annual mortality and morbidity of influenza.

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.

Viral cell culturing has become a commonly used method for the cultivation of viruses. Before cell cultures, many viruses were propagated by the use of an embryonated egg. However, today embryonated eggs are still used for the production of vaccines and for the isolation of avian and influenza viruses. In addition, there are several procedures that must be carried out when a virus is grown in an embryonated egg. For instance, the eggs must be candled (to determine viability) and disinfected before a hole is drilled. Next, the virus must be injected into the appropriate area of a 5-14 day old embryonated egg. Signs of successful viral growth include pocks, hemagglutination, or death of the embryo 2-5 days after injection. In this lab, the purpose was to inject Influenza A Virus (H1N1) strain APR/8/34 into the chorioallantoic sac of a 9-11 day old embryonated egg. Our hypothesis was that the Influenza A virus will grow successfully in the embryonated egg to yield successful results for the following lab.

Wild aquatic fowl, ducks in particular, serve as a reservoir for the Influenza virus to transmit into poultry and then to humans. Infected birds shed flu viruses in their saliva, nasal secretions, and feces (CDC, 2004). The current virus seen in Asia is denoted as H5N1 and was first seen in terns in South Africa in 1961 (CDC, 2004). The first human seen infection of the avian H5N1 viruses was in 1997 in Hong Kong in a three- year old boy (Ruben, 2005). The outbreak involved 18 cases and killed 6, one third of the confirmed infected population (Rueben, 2005). In three days 1.5 million birds were killed in order to prevent further spread. A new pandemic is now on the horizon with recent outbreaks in poultry in the eight Asian countries of Cambodia, China, Indonesia, Japan, Laos, South Korea, Thailand, and Vietnam since 2004 (CDC, 2005). As of July 5, 2005, there have been 108 reported human cases of the H5N1 virus with 54 deaths (CDC, 2004). In wake of a

Once there was a virus named Birdie. This virus was a Bird Flu, or Avian Influenza, virus of the subtype H5N1, the first strain of Avian Influenza having the ability to infect humans (Normandin and Solan). Birdie looked like a microscopic pomander, a fragrant orange with cloves stuck in it. Inside, she had eight pieces of single stranded ribonucleic acid or ssRNA. Birdie was deadly to humans, but was not able to spread from one human to another. She could only spread from birds to humans ("Bird Flu"). Birdie started out inside a chicken named Cluck, where she was formed. A little while later, Cluck's farmer Mark, sold his Cluck, to Joe, another poultry farmer because Mark did not realize that Cluck had H5N1. After a few months of Cluck living

Patients with influenza-like illness from October 2009 to December 2012 were enrolled. The outpatients enrolled were followed for 14 days while the inpatients were for 60 days. Patients with disease progressive were confirmed by RT-PCR. The patients were defined as outpatients (hospitalized and/or death) and in the hospital for more than 28 days. The inpatients were defined as patients who were transferred to ICU who were from the general ward or near death. In the data collected, 590 FLU 002 and 392 FLU 003 patients with influenza A (H1N1) pdm09 were enrolled from 81 sites in 17 countries at 2 days (IQR 1–3) and 6 days (IQR 4–10) following ILI onset, respectively. 29 (1 death) outpatients (5.1%; 95% CI: 3.4–7.2%) and 80 inpatients [death (32), hospitalization >28 days (43) or ICU transfer (20)] (21.6%; 95% CI: 17.5–26.2%) experienced the progression of the disease. The

Influenza A is the worst of the three kinds. According to source 1, flu type A can infect animals, though it is more common among humans. Wild birds are common hosts. Influenza A2 is spread by people who are already infected. It can be spread by sneezing and coughing. Influenza A is the type of flu you get a shot for. It can cause epidemics and pandemics. This is important because we need to know why doctors

Following isolation of a confirmed or suspected H7N9 infected patient, treatment involves the standard Influenza A flu treatments to ease symptoms along with antiviral drugs to prevent the infection from getting worse. For example, the use of antipyretics (fever reducer), cough suppressants, and expectorants (loosens mucus) along with adequate sleep and water is recommended [26]. In patients with severe respiratory symptoms, such as ARDS, mechanical ventilation is also critical for treatment [26,19]. Patients with secondary infections that may occur in damaged lungs, such as bacterial infections, may also require antibiotics on top of the influenza A treatments [26]. Furthermore, current treatment also involves immediate treatment with neuraminidase

Influenza is one of the most contagious illnesses caused by airborne viruses. I can lead to mild or severe illness and even death. Influenza can come suddenly and is marginally different to a ‘Cold”. The virus can cause infections of the lower respiratory tract (lungs) and the upper respiratory tract (throat, nasal). Influenza is disease that may cause symptom such as the following; fever (high body temperature), sore throat, muscle or body aches, cough, Headaches, runny or stuffy nose, fatigue/tiredness (CDC, 2016). it belongs to “Orthomyxoviridae” family of infections, “myxa” meaning ‘mucus’ in Greek. There are three major types of influenza that may also be addressed as different terminologies, such as flu

Influenza viruses are negative-stranded, segmented RNA viruses. They belong to the family of orthomyxoviridae and are major pathogen of both humans and animals. They are one of the leading causes of respiratory tract infections in humans and animals. Upon the viral infection, both innate and adaptive immune responses are induced. The virus is continuously undergoing antigenic change and thus bypasses the host's acquired immunity to influenza. The difficulty in generation of antibodies against the virus is because of frequent antigenic drifts. Now it is found these shifts involve subtle changes in the antigenic configuration of hemagglutinin and neuraminidase. Despite the improvement in antiviral therapy during the last decade, vaccination

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”