IndexAbstractIntroductionCausative agentThe extent of the problemPredisposing factorsComplex People who are at increased risk of contracting this virus includeTransmissionClinical presentationPrevention and controlVaccinationConclusionReferencesAbstractH1N1 swine influenza is a subtype of the influenza A virus, which differs from other strains (H1N1, H1N2) in the surface glycoproteins hemagglutinin and neuraminidase. Primarily, the spread of this new virus is believed to occur through respiratory droplets; Coughing, sneezing, touching respiratory droplets to yourself, another person or an object, then touching mucous membranes (e.g., mouth, nose, eyes) without washing your hands. Once infection occurs, the clinical spectrum of infection ranges from mild upper respiratory tract disease to severe complications such as pneumonia resulting in respiratory failure, acute respiratory distress syndrome (ARDS), multiple organ failure, and death. This new H1N1 virus was first reported in 2009 in Mexico, then WHO officially declared the beginning of the 2009 influenza pandemic in June 2009. The scale of this pandemic was enormous. It not only affected the health and healthcare of the community, but also affected other economic and social aspects. Various measures have been implemented for the prevention and control of H1N1 infection, including pharmacological and non-pharmacological interventions. Due to the enormous demand for in-depth studies of this new virus, this article highlights the magnitude of the problem, the potential for transmission and predisposing factors. Furthermore, it explores the various dimensions of clinical presentation, prevention and control. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Introduction H1N1 swine flu is a widespread infection in pigs worldwide and is also known as swine flu for this reason. H1N1 swine flu contributes to respiratory disease and can theoretically affect the pig's respiratory tract. Occasionally people who are closely related to or close to pigs develop swine flu (zoonotic swine flu). Swine influenza viruses have the potential to cause human infections if the virus changes its antigenic characteristics by reassortment. Influenza A pandemics such as those that occurred in 1918 and 2009 can occur when person-to-person transmission is successful. In 1918, a devastating influenza pandemic caused by the H1N1 influenza virus, also known as the Spanish flu, marked it as one of the deadliest pandemics in human history. In 2009, the swine-human influenza (H1N1) epidemic, which is likely to spread from pigs to humans, began in Mexico and quickly spread to many countries around the world. This new "pandemic" has been attributed to a triple-carried influenza A virus of swine, Eurasian avian, and human strains, although it is unclear when and where the reassortment occurred. Causative agent The H1N1 influenza virus is an orthomyxovirus, which develops virions with an RNA genome of diameter between 80 and 120 nm. The swine influenza genome has 8 different regions that are segmented and encode 11 different proteins: Proteins envelope hemagglutinin (HA) and neuraminidase (NA) Viral RNA polymerases including PB2, PB1, PB1-F2, PA, and PB Matrix proteins M1 and M2 Nonstructural proteins NS1 and NS2 (NEP ), which are crucial for efficient viral pathogenesis and replication. The surface glycoproteins HA and NA are how the H1N1 strain varies from another strain of influenza A (H1N1, H1N2) todepending on the type of HA or NA antigens expressed with metabolic synergy. Hemagglutinin has the function of causing red blood cells to bind together and binding the virus to the infected cell. Neuraminidase helps move virus particles through infected cells. The extent of the H1N1 influenza problem was first reported in Mexico on March 18, 2009. Within weeks, the epidemic spread to 30 countries. By June 11, the WHO officially declared the start of the 2009 influenza pandemic by reporting the phase 6 alert level as nearly 30,000 cases of the 2009 H1N1 virus had been confirmed in 74 countries. The infection was recorded in 122 countries by July, with 134,000 laboratory-confirmed cases and 800 deaths. The scale of global trade and travel allowed the swine flu outbreak in six weeks to be at the same level as previous pandemics in six months. As of December 2009, more than 208 countries and territories had reported cases of swine flu. As of March 2010, nearly all countries have recorded cases and more than 17,700 deaths among laboratory-confirmed cases. In the United States, as of mid-February 2010, an estimated 59 million illnesses, 265,000 hospitalizations, and 12,000 deaths were caused by the 2009 H1N1 virus. It is important to note that the mortality estimate may have been an underestimate because it was based on statistical data . attribution of excessive all-cause mortality rather than laboratory-confirmed cases. According to the Ministry of Health, the number of laboratory-confirmed cases in Saudi Arabia as of December 30, 2009 was 15,850, with 124 deaths. In addition to the medical impact, the pandemic has also been the cause of social upheaval. It has negatively affected global tourism, with airlines reporting tens of millions in losses. In Mexico, international air traffic to/from the country decreased by 40% following travel controls by some countries during the early stages of the outbreak in an effort to contain or slow its international spread. Furthermore, in the United States, school closures for an average of four weeks cost up to $47 billion (0.3% of GDP) with a 19% reduction in key healthcare personnel. Predisposing Factors Overall People who are at increased risk of becoming ill from this virus include children under 5 years of age. Adults older than 65 years, younger adults, and children younger than 19 years on long-term aspirin therapy. People with compromised immune systems due to diseases such as AIDS. Women currently pregnant. People suffering from chronic diseases such as asthma, heart disease, diabetes mellitus or neuromuscular diseases. Transmission The potential mode of transmission occurs through droplets from coughing or sneezing and direct or indirect contact with the respiratory secretions of an infected person. Handling surfaces contaminated with viruses (fomites) and inhaling bacterial aerosols into the nose or mouth. Fomites are inanimate objects (e.g. children's toys) which, through indirect contact, can act as vehicles for the spread of the disease. Infectious aerosols are composed of large droplets and droplet nuclei. Large respiratory droplets have a diameter >5-10 μm and are involved in short-range transmission. The diameter of the droplet nuclei is <5 μm and is responsible for long-distance transmission (long-range or airborne transmission). Rapid spread has been observed among the population, especially in crowded places such as schools. Clinical presentation The symptoms of H1N1 are similar to those of seasonal influenza: fever, cough, sore throat, malaise, headache, myalgia, arthralgia and fatigue. Manypatients, especially in the pediatric age group, presented with vomiting and diarrhea, which are not commonly seen with seasonal influenza. Available data suggest that the clinical range of H1N1 virus infection is broad, ranging from mild upper respiratory tract disease to severe complications such as respiratory failure, acute respiratory distress syndrome (ARDS), multiple organ failure, and death. Gastrointestinal symptoms such as diarrhea have been reported in 20% to 50% of patients and do not require hospitalization. For some countries, primary viral pneumonia or viral pneumonia is the leading cause of hospitalization. Microbiological evidence of secondary bacterial or fungal infections has been found in fatal events... In the United States, >70% of hospitalized patients and approximately 80% of fatal cases had underlying conditions considered to be at high risk for complications. Surveillance data on hospitalizations and deaths due to H1N1 infection show that people who are pregnant, at extreme ages, and who have underlying chronic illnesses are at increased risk for severe or complicated influenza illness. An additional risk factor that has emerged with this influenza pandemic is obesity (body mass index, Q30 kg/m2), a characteristic that was not prevalent in previous seasonal influenza epidemics. Similarly, information on the incubation period of this virus was derived from that of seasonal influenza and varies from 1 to 7 days. It is assumed that children with ILI shed the virus from the day before the fever until 7 days after the onset of the disease; viral shedding may be longer in some groups such as infants and immunocompromised children. For prophylaxis, the infectious period of influenza is defined as 1 day before the onset of fever until 24 hours after the end of fever. Prevention and Control Various pharmacological and non-pharmacological intervention measures are applied by developing countries to limit and prevent the disease. Non-pharmacological measures include: personal hygiene, washing hands with soap, covering mouth and nose when coughing and sneezing, avoiding crowded places, cancellation of social events such as weddings and closure of schools and shopping centres. Mandatory isolation of cases and quarantine of close contacts. Healthcare workers should collect clinical specimens with appropriate biosafety facilities and protective equipment should be used during procedures. For pharmacological measures: antiviral drugs (oseltamivir and zanamivir) are recommended and the drug of choice for H1N1 influenza should be administered within 48 hours of the onset of symptoms and the priority is for these patients with risk factors for serious diseases such as elderly patients (>65 years), pregnant women, patients with immunosuppression or chronic diseases such as asthma and young children (148 hours after the onset of symptoms. Antiviral prophylaxis should be administered to healthcare professionals for a maximum duration of 6 weeks for oseltamivir and 4 weeks for zanamivir, patients in close contact and who are not provided with prophylaxis should also take early treatment with an antiviral drug. Vaccination The vaccine is available in some countries. It is the most effective measure to prevent morbidity and mortality associated with influenza based on the A/California/07/2009 (H1N1) strain, is available in both live attenuated and inactivated formulations. A single dose is adequate for individuals older than 9 years, and immune responses have been observed in 80% to 96% of patients. adults aged 18 to 64 and 56% to 80% of adults aged 65 and older. Children younger than 10 years will require two doses separated by at least 21 days. Thelive attenuated vaccine is intended only for people aged 2 to 49 years who are not pregnant, immunocompetent and have no chronic diseases and is contraindicated in children under five years of age who suffer from asthma, in children receiving aspirin for a long time term and in those in close contact with immunosuppressed people. The inactivated vaccine is contraindicated in patients with severe allergic conditions to eggs or any component of the vaccine. Please note: this is just a sample. Get a custom paper from our expert writers now. Get a Custom Essay Conclusion H1N1 is a subtype of the influenza virus that triggers upper and lower respiratory tract infections, the number of labs in Saudi Arabia as of December 30, 2009 was 15850, with 124 deaths… It spreads through droplets from coughs or sneezes, through direct or indirect contact with the respiratory secretions of the infected person, through proximity to objects contaminated by the virus (fomites), through contact with the nose or mouth and through inhalation of infectious aerosols. Patients usually have fever, cough, sore throat, malaise, headache, myalgia, arthralgia and muscle fatigue, any inflammation of the gastrointestinal tract can also cause. Public grooming, soap for hand washing, and covering the mouth and nose when coughing and sneezing are prevention strategies, and antiviral prophylaxis may also be used. There are two types of live attenuated and inactivated vaccines used respectively. 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