The 2009 flu pandemic is a global outbreak of a new strain of a influenza A virus subtype H1N1, officially named the "new H1N1", first identified in April 2009, and commonly called "Swine flu." It is thought to be a reassortment of four known strains of influenza A virus[98]: one endemic in (normally infecting) humans, one endemic in birds, and two endemic in pigs (swine). Transmission of the new strain is human-to-human, with cooked pork products safe to eat as the virus cannot be transmitted by eating foods.
The outbreak began in Mexico, with evidence that Mexico was already in the midst of an epidemic for months before the outbreak was recognized[citation needed]. Soon after Barack Obama's visit to the country, its government closed down most of Mexico City's public and private offices and facilities to help contain the spread. In early June, as the virus spread around the planet, the World Health Organization (WHO) declared the outbreak to be a pandemic, but also noted that most illnesses were of "moderate severity."
The virus has since spread to the Southern Hemisphere which entered its winter flu season, and to many less developed countries with limited healthcare systems. Because the virus was spreading with "unprecedented speed", and many clinics were overwhelmed testing and treating patients, WHO stopped requiring countries to report all cases, but is still monitoring unusually large outbreaks.[99][100]
Like any other flu, the virus typically spreads from coughs and sneezes or by touching contaminated surfaces and then touching the nose or mouth. Symptoms, which can last up to a week, are similar to those of seasonal flu, and may include fever, sneezes, sore throat, coughs, headache, and muscle or joint pains. The U.S. Centers for Disease Control and Prevention (CDC) notes that most cases worldwide are usually mild, and most hospitalizations and deaths have been of persons that also had underlying conditions such as asthma, diabetes, obesity, heart disease, or a weakened immune system. The CDC's Anne Schuchat states, "this is a virus that's capable of causing a spectrum of illness that includes severe complications and death. . . It's very important we take this virus seriously".[101]As the virus spreads easily between people, through the air or surface contact, those who get the flu are recommended to stay home from school or work and avoid crowds to avoid spreading the infection further.
In an attempt to slow the spread of the illness, a number of countries, especially in Asia, have quarantined airline passengers with flu symptoms, while some are also pre-screening passengers. WHO does not expect to have a full vaccine before the end of 2009, and vaccines available sooner may be limited and given first to healthcare workers, pregnant women, and other higher risk groups. Two or three injections will be required for maximum immunity from both the swine flu and seasonal flu.[citation needed] The World Health Organization is also concerned if the new virus mutates further, it could become more virulent and less susceptible to any new vaccine.
HISTORY:
Influenza surveillance information "answers the questions of where, when, and what influenza viruses are circulating. It can be used to determine if influenza activity is increasing or decreasing, but cannot be used to ascertain how many people have become ill with influenza".[102] Estimating deaths from influenza is also a complicated process. In 2005 influenza only appeared on the death certificates of 1,812 people (USA only). The average annual toll from flu is, however, estimated to be 36,000[103] (USA only). The CDC explains[97] that "…influenza is infrequently listed on death certificates of people who die from flu-related complications." and furthermore that "Only counting deaths where influenza was included on a death certificate would be a gross underestimation of influenza’s true impact."
The last WHO update, issued on July 6, showed 94,512 confirmed cases in 122 countries, with 429 deaths. Many epidemiologists have pointed out that, in reality, millions of people have had swine flu, usually in a mild form, so the numbers of laboratory-confirmed cases were actually meaningless.[100] Partly as a result, on July 16, WHO announced that it "will no longer issue the global tables showing the numbers of confirmed cases for all countries".[99] Instead, national health authorities from all countries should inform WHO on a weekly basis of their qualitative assessment of the geographical spread, trend of cases, intensity of disease, impact on the health‐care system, and deaths.[104]
In the U.S. as of July 17, the number of confirmed infections was 40,617, with 263 deaths, according to the CDC. But the agency believes that more than one million people have been infected and weren't tested for the virus or didn't visit a doctor. Since the disease has now become so widespread, the CDC says it too will "probably" suspend counting cases within the next few weeks and focus instead on tracking clusters, severe cases, deaths and other unusual events.[105]
Early reports
The initial outbreak received a week of near-constant media attention.[106] Epidemiologists cautioned that the number of cases reported in the early days of an outbreak can be very inaccurate and deceptive due to several causes, among them selection bias, media bias, and incorrect reporting by governments.[107] Inaccuracies could also be caused by authorities in different countries looking at differing population groups.[107] Furthermore, countries with poor health care systems and older laboratory facilities may take longer to identify or report cases.[108]
The CDC in late May stated that counting confirmed cases had become "largely irrelevant," and switched instead to its traditional surveillance systems for monitoring flu-like symptoms by looking for patterns, clusters and changes in flu activity nationwide. According to the CDC, surveillance methods, along with rapid isolation and treatment, only makes sense at the very earliest stage of an outbreak, and "becomes irrelevant" once the virus is spreading widely within the community, as it is in the United States.[109]
In some instances, governments accused other countries of intentionally underreporting cases. Moscow, for instance, hinted that the Dominican Republic was under-reporting cases to "boost tourism." [110] In early May, Cuba's Fidel Castro accused Mexico of hiding the scope of the epidemic until after President Obama visited the country in April.[111]
In the U.S. data accuracy has also become an issue, with some school districts deciding to keep the names of students and schools that have reported infections confidential, one stating that "it would not be fair to single out one school," since doing so would be likely to trigger requests by parents to have their children tested despite their health not being in danger, and the schools lacking the ability to test everyone.[112] Dr. Hector Gonzalez, Director of the Laredo Health Department, said that according to CDC guidelines, physicians only need to submit samples for testing if the patient is a child under 5 years of age, is pregnant, has an underlying medical condition or is suffering from respiratory distress requiring urgent care.[113]
Test accuracy
In early June, WHO and the U.S. Food and Drug Administration (FDA) acknowledged that a new laboratory test used to identify the virus was about 90 per cent accurate, [114] while rapid diagnostic tests have an accuracy of 50-70%. To be safe, some experts suggest, anyone who exhibits flu like symptoms (sore throat, cough, fever), should be presumed to have swine flu until there is concrete evidence to the contrary.[115]
Historical context
Annual influenza epidemics are estimated to affect 5–15% of the global population. Although most cases are mild, this still causes severe illness in 3–5 million people and around 250,000–500,000 deaths worldwide. In industrialized countries severe illness and deaths occur mainly in the high-risk populations of infants, the elderly, and chronically ill patients.[116]
In addition to these annual epidemics, Influenza A virus strains caused three major global epidemics during the 20th century: the Spanish flu in 1918, Asian flu in 1957 and Hong Kong flu in 1968–69. These pandemics were caused by strains of Influenza A virus that had undergone major genetic changes and for which the population did not possess significant immunity.[116][117] The overall effects of these pandemics and epidemics are summarized in the table below.
Vaccination Recommendations
With the new H1N1 virus continuing to cause illness, hospitalizations and deaths in the US during the normally flu-free summer months and some uncertainty and about what the upcoming flu season might bring, CDC's Advisory Committee on Immunization Practices has taken an important step in preparations for a voluntary novel H1N1 vaccination effort to counter a possibly severe upcoming flu season. On July 29, ACIP met to consider who should receive novel H1N1 vaccine when it becomes available.
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SUGGESTIONS:
Citizens are hereby informed to wear msaks while roaming in the places where chances of infection are high
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