la grippe A

Terminology

Originally called swine flu by the World Health [7], this flu has also been named by various international institutions, avian North American [8] flu [9] or new influenza [10] before the WHO does not recommend the name of influenza A (H1N1) April 30, 2009 [11], [12].

The flu of 2009 is indeed the H1N1 subtype of influenza A, like other influenza pandemic, in particular the 1918 flu, called "Spanish flu".
Characteristics of viruses
Reassortment of the virus genome of influenza A H1N1 in 2009

Dr. Anne Schuchat (Centers for Disease Control and prevention of diseases in the United States (CDC)), said that American cases are the result of a virus characterized by a recombination of genetic elements from four different viruses:

* Swine flu in North America,
* Avian flu in North America,
* A human influenza type A subtype H3N2, and
* A swine flu virus typically found in Europe and Asia;

is "a unique mixture and never met nor the United States or elsewhere, genetic sequences [13]. This new strain might result from secondary infection in an individual patient.

For two isolates, the complete genomic sequences have been obtained [ref. necessary]. These are used by U.S. researchers to develop a vaccine. Dr. A. Schuchat said [14] that the virus is resistant to amantadine and rimantadine, but susceptible to oseltamivir (Tamiflu) and zanamivir (Relenza).
On the basis of data available on 1 May 2009, A. Schuchat estimated that every household in a sick person contaminating quarter averaged about other family members, as in the case of seasonal flu, and at the same time, Dr. Nancy Cox (head of the U.S. CDC flu ) do not find this virus in "markers of virulence were observed in the 1918 virus, while remaining cautious due to the fact that the dangers of influenza viruses remains poorly understood [15].

Preliminary genetic characterization showed that the gene for hemagglutinin (HA) is similar to the virus of swine influenza present in the United States since 1999, but the genes for neuraminidase (NA) and matrix protein ( M) similar to variants found in isolates of European swine influenza.
Epidemiology
Morbidity
Structure influenzavirus.

The disease is linked to infection (a disease is most contagious disease is more his forte), but other factors are considered, whose state of health and hygiene conditions of the population (alcoholism, smoking, undernutrition), or the precautions taken to prevent the spread of the disease. The disease varies widely, depending on the flu, the influenza A (H1N1) (very recent onset) is a source of more questions than precise answers. However, general knowledge of influenza allows some answers, still partial.

The common flu (called "seasonal") has a high morbidity: it affects between 5% and 15% of the population.
In contrast, avian influenza is very contagious and spreads evil in humans. On the whole planet, the number of people affected totaled only about four hundred years [16]. Several clues suggest that the morbidity of influenza A (H1N1) is closer to seasonal influenza as bird flu. The first of them from the virological analysis, it shows the existence of elements from the swine flu [13]. History teaches us that the flu with origins can be contagious pig [17] as was the flu in Hong Kong in 1968 [18].

An important factor in the danger of this virus is its ability to deploy a more or less extensive in the world. Some epidemics, whether due to a highly infectious virus remained local. This was the case in Madagascar in July and August 2002: an epidemic caused by a virus of type A (H3N2). In some areas it has reached up to 85% of the population, but remained limited to a geographical space of four of the six provinces and has not left the island [19]. The local nature of flu is not a generality, some of them spread over a large part of the world, including influenza A (H1N1).

Among the certainties:

* The disease is transmitted from human to human without going through the animals [20], and the disease has spread in several different countries;
* The disease remains poorly understood, the statistics are too small to draw definite conclusions [21];
* The virus seemed more "hard" area in the southern winter (eg in Chile: 3.8% of cases confirmed by laboratories that have required hospitalization, and 0.2% (16 cases) resulted in death the patient and there were at that date 16 deaths in Mexico between May 17 (Case 1) and mid-June 2009 to 8 160 cases identified, often reported in the south (colder and rainy during the austral winter), and 53% of reported patients were young (5 to 19 years) [22].

Lethality
Subtypes of Influenzavirus.

Influenza A (H1N1), like seasonal influenza, can, in rare cases, cause death of patients by three different mechanisms.

* The first is death by bacterial infection, has become rare in developed countries due to the accessibility of antibiotics.
* The second is a viral lung infection entrainant syndrome acute respiratory distress (ARDS) lethal in 50% to 60% of cases.
* The third most common is the worsening of preexisting disease in a person sensitive [23].

The overall mortality of the influenza A (H1N1) remains low although there are differences across countries.

The different flu is also widely variable. She is particularly based on the lives of people, types of populations, and health resources of countries in which they live.

Globally, seasonal influenza kills each year between 250 000 and 500 000 people [18]. In France, influenza kills between 1 500 and 2 000 persons per year [24] and it kills each year about 36 000 in the United States [25]. It does not kill but that the fraction of the population most vulnerable: the elderly, those suffering from long-term illnesses or younger children [18]. This profile fatality seems to be emerging for influenza A (H1N1) and rich countries. Richard Besser, director of the federal Centers for Control and Prevention (CDC) says it is "encouraging that the virus did not seem far more severe than seasonal flu strain [26].

These reassuring signs do not apply in Mexico. If the proportions are different in nature from those of rich countries: 42 deaths of 1 112 cases confirmed in May 8, 2009, this is not the most worrying [18]. The figures are unreliable, the WHO said that the recent growth is mainly due to statistical bias and not an actual disease progression [18]. Dr. Richard J. Webby says, "because the symptoms of influenza A are the same as those of seasonal flu, this fatality might simply reflect hundreds of thousands of infected people who have escaped the Official Mexican health" [27]. The actual number of deaths is probably larger and 101 more deaths are deemed suspicious [28]. In Mexico, severely affected individuals are not necessarily part of the population most vulnerable [29], this qualitative element suggests a fatality profile different from that of rich countries.

If the past 40 years, no rich country has experienced an epidemic of flu more deadly than seasonal, this situation is different for the less medicalized. The outbreak in Madagascar in 2002 had been 754 deaths on 30 304 cases reported [19]. Some parts of the world have no way to avoid an epidemic if it arises, and effective treatment of its population. This is the case of Somalia, its medical centers are destroyed by civil war. The adviser to the Minister of Health stated that "We are not prepared to manage the swine flu ... May God help us if the flu comes up [30].

Regarding the assessment of total cases, Anne Schuchat of the CDC evaluates May 22 through 1 20 the number of confirmed cases in the United States, that is to say, 20 patients for each confirmed case [31] . "In fact, a minority of cases are counted individually. Some media reports of evaluations around a million cases in the country [32], [33].

This report is valid for United States of America and may vary greatly from one country to another (depending on how tests are conducted [34]). Thus Professor John Oxford of the United Kingdom considers for its part in 1 in 300 confirmed cases there [35].

Brazil, where the swine flu has killed 657 people (August 2009), is the country with the largest number of deaths due to H1N1 in the world. [36]
Hypothesis about the origin of pandemic
Mexican Catholics equipped with surgical masks to the Metropolitan Cathedral in Mexico City.

One of the largest industrial pig farms located in La Gloria in the region of Perote in the state of Veracruz, Mexico, is suspected by the local population strongly affected and surrounding authorities, to be the origin of the pandemic [37].

Initially, Mexican authorities believe to have found Patient Zero: Edgar Hernandez, sick in late March of a proven case of H1N1 [38]. However, April 30, the control center in Atlanta published a report on another case in Mexico who developed the virus mid-March, 15 days before Hernandez [39].

On June 23, 2009, the New York Times reports that the Department of Agriculture of the United States said that "contrary to common assumption is that the virus pandemic flu originated from farms in Mexico" The virus' most likely emerged in pigs in Asia and traveled to North America in a human [40].

Dans son numéro de juillet-septembre 2009, le magazine l'Écologiste défend le point de vue que « l'élevage concentrationnaire des animaux favorise les recombinaisons de virus », en s'appuyant sur des références scientifiques[41].
Symptoms
Symptoms of infection with influenza virus A (H1N1) (English).

This new strain of influenza causes the same symptoms as seasonal influenza [42]:

* The incubation period is 24 to 72 hours,
* Fever brutal and high, exceeding 38 ° C
* Muscle pain and / or joint
* Fatigue important
* Pain in the throat and possibly headaches,
* Cough deep and rather dry
* Congestion & Runny Nose
* Loss of appetite,
* In some cases, vomiting and diarrhea.

The symptoms usually disappear in a week to ten days after their appearance, but fatigue and cough may sometimes persist for two to three weeks. The infected can be contagious one day before symptoms appear and remain for seven days.
Rapid tests

Several rapid tests (or RIDT Influenza Rapid Diagnostic Tests) have recently appeared on the market which can theoretically detect (in 15 minutes) several type A viruses, including H1N1.

These tests are still imperfect and may contribute to under-diagnose cases.
Beginning in August 2009, CDC released preliminary results of a study focused on 3 rapid diagnostic tests [43] put on the market to detect influenza A (H1N1) in samples (non-free here, but retained by CDC) in respiratory secretions.
The study confirmed that the new H1N1 could be detected by these tests, but not in all cases these three tests have frequently failed to identify virus in samples where the virus was not strongly present (sensitivity is low or very low when the viral titer is low, "according to the CDC concluded:" A negative result does not exclude it either infected with influenza A (H1N1).

* Of the 35 samples containing a low rate of influenza A (H1N1), one of the tests (BinaxNOW) has detected the virus in 40% cases, while the Directigen EZ Flu A + B not detected that in 49% of these samples and the QuickVue influenza detected in 69%.
* Reliability is not very high for samples heavily contaminated by the virus of 9 samples rich in influenza A (H1N1), two of three tests have failed to identify it in case. [44], [45], [46]

A RIDT negative rapid test does not mean the absence of infection.
Prevention
Surgical masks and hygiene
Article: surgical mask and Hygiene.
Chinese health inspectors investigating the case of fever, classic symptoms of influenza A (H1N1).

Surgical masks are a way of limiting the spread of a pandemic. Carried by infected persons, these masks limit the spread of the virus into the air by coughing and sneezing. Upon activation of the emergency plan, they are distributed by the army and are available in large numbers in hospitals and clinics. The masks allow FFP to protect people who wear them. Only masks type FFP2 or FFP3 are effective against the influenza virus A (H1N1). [47]

Note that these masks can be a vector of contamination when they were infected by the virus. It must change mask if possible for each potential exposure to the virus (eg, surgical masks for "care" when one has sneezed or coughed in, as moisture passes through them) and without touching the part filter with your hands.

As with many infectious diseases, one of the best forms of prevention is hygiene. Thus, to prevent contagion during epidemics, it is necessary to wash hands with soap several times a day or use alcohol-based disinfectants to disinfect their hands, especially after any physical contact with a person potentially infected, or with surfaces potentially contaminated by the virus [48].
Antivirals
Article: Oseltamivir.
Box of Oseltamivir (Tamiflu).

Neuraminidase is a viral protein that allows viral particles can diffuse into the bloodstream and thus go on to infect adjacent healthy cells. The neuraminidase inhibitors prevent the virus can cross the plasma membrane of the infected host cell. The cell and overloaded by the virions was destroyed with the virus.

These inhibitors are oseltamivir (Tamiflu) and zanamivir (Relenza). They reduce the duration of clinical signs of one or two days and reduce the infectiousness of the patient [49]. According to British doctors, these drugs should not be prescribed to children under 12 years because of side effects [50], [51]. These side effects, affecting one child in two, are for the most common: nausea, headache, pain or stomach cramps, nightmares. The gastrointestinal effects (nausea, vomiting, diarrhea, upset stomach) were reported by 40% of children [52].

In 2009, Roche Laboratories and GlaxoSmithKline, manufacturers of Tamiflu and Relenza, increase production of antivirals and say they can meet in January, 400 million doses per year [53].

The stocks of antiviral drugs are managed in France by the health department of the army (Pharmacie Centrale des Armées) and the Ministry of Health. They are distributed in almost all major health centers (CHU, CH, CHR) and are subject to prescription in order to minimize any temptation to illegal trade and business case.

A first case of Tamiflu resistance has been observed in a patient Danish June 29, 2009. The patient was cured with another antiviral (Relenza) [54], which proved effective. According to WHO, it would be an "isolated case" no "involvement in terms of public health" [55]. Other cases have been observed near the border between the United States and Mexico. [56].
The vaccine
Article: Vaccine Influenza A (H1N1) in 2009.

While the first vaccines were advertised as potentially available in early July by Novartis [57], it finally seems that we should wait until the fall of 2009 before receiving them [58]. Furthermore, specific vaccines for infants would be considered. The first clinical trials which aim to demonstrate the effectiveness of the vaccine, the absence of side effects, determine the best dose and the optimal strategy started in August [59].

France has ordered 94 million vaccines, 34 million optional for 2010 from three laboratories (Sanofi-Pasteur, GlaxoSmithKline (GSK) and Novartis). The first vaccines will be reserved for those working in health, relief and security.

The CDC initially said that two injections are needed at three week intervals for influenza A (H1N1) (and another for seasonal flu) to provide maximum protection. Children under nine years may be in need of four injections. "An injection will likely have little immunity, 10 to 20 per cent more [60].

In June, the Secretary of Health and Social Services of the United States, Kathleen SebeliusKathleen Sebelius has signed a decree granting immunity to manufacturers of vaccines against H1N1 influenza, in case of legal action following the new vaccine against the avian [ 61], [62]. The U.S. government took this measure to encourage manufacturers to produce the vaccine.

On July 31, 2009, in Greece, Health Minister Dimitris Avramopoulos told reporters that "on instructions from Prime Minister (Costas Karamanlis), it was decided to vaccinate all residents and nationals of countries without exception [63].

On August 7, 2009, the laboratory Baxter announced availability of a vaccine (the CELVAPAN) and is in talks with health authorities for distribution [64] This said a vaccine or mock-up "vaccine-model, a adapted version of the pre-pandemic vaccine originally developed against the virus influenza A (H5N1). The prototype had already authorized the placing on the market (AMM) granted by the European Medicines Agency (EMEA). This process allows for accelerated approval of pandemic vaccine, without filing a new application for marketing authorization.

The first evaluation of the vaccine published September 10, 2009 found a good efficacy (for a target strains recommended by WHO), the protection seems rather high, even with a single vaccine side effects rather limited [65 ], but these tests have focused on the vaccine without the adjuvant which can also cause side effects) [66].

The vaccine against seasonal influenza but may have a partial preventive efficacy against H1N1 [67].
Production of vaccines

Sanofi Pasteur, GlaxoSmithKline (GSK) and Novartis are using embryonated chicken eggs to grow the virus while Baxter uses cell kidney African green monkey virus culture.

Two types of vaccines are being prepared in the laboratory. One, created from scratch will take months to complete all the steps necessary for validation. The second, said vaccine "mock-up" or mock-vaccine was prepared in response to the epidemic of H5N1 avian influenza. To expedite the process, mercury was used [68]. All vaccines were prepared model with a strain of H5N1 influenza viruses that must be changed from August 20, 2009 for the H1N1 strain that is causing the pandemic [69]. The European Commission has approved the marketing of four vaccine models:

* CELVAPAN, Baxter AG;
* Daronrix, GlaxoSmithKline Biologicals S.A.;
* Focetria, Novartis Vaccines and Diagnostics Srl;
* Pandemrix, GlaxoSmithKline Biologicals S.A.

Answers
Cases and reactions by Country
Article: Influenza A (H1N1) in 2009 by country.
Outbreak of influenza A (H1N1) in 2009. Black: confirmed dead. Red: confirmed infections. Orange suspected cases.
See also: Outbreak of influenza A (H1N1) in 2009

The new flu has spread throughout Mexico, with cases confirmed in at least 125 countries [70]. Countries including Australia, China, Iceland, India, Indonesia, Malaysia, Philippines, Singapore, South Korea and Thailand monitor travelers from affected areas to identify people with respiratory symptoms and fever.

Many countries have also warned travelers of areas affected by avian contact a doctor immediately if they had flu symptoms. Several countries have also banned the import and sale of pork [71], [72].

The Egyptian parliament has asked that the 250 000 pigs in the country are killed immediately [73].

The first cases of influenza A were detected among Amazonian Indians in August 2009 in 10 Indian matsigenka all since recovered, living near the Urubamba river in Peru. Isolated populations in the forest generally have little immunity against such diseases. Experts fear an epidemic of more serious consequences than in urban areas [74], [75].

In France, and systematically, the people who had contact (less than 1 minute) with the patient during the 24 hours before reporting symptoms, are quarantined for a period of 24 hours and are prescribing Tamiflu and wearing a mask. The first case was confirmed at the meeting in the Indian Ocean, July 6, 2009 [76].

Some personalities have been affected by the epidemic but are not dead

* Costa Rican President Óscar Arias Sánchez [77]
* Turkish actress Müjgan Gönül [78]
* Colombian President Alvaro UribePresident Alvaro Uribe [79]
* British actor Rupert GrintRupert Grint [80]
* Player of the rugby team of French Barbarians, whom Gregory Lamboley [81]
* Football players Paris Saint-Germain striker Ludovic Giuly and defender Mamadou Sakho [ref. necessary]

The vaccination plan in autumn 2009 in France

In a circular dated August 21 addressed to prefects [82], the Ministers of Interior and Health has said the vaccination plan commencing September 28 they call "progressive health response Exceptional. It is stated that the government "has ordered doses of vaccine, to be able to propose, if necessary, to the entire population immunization coverage against the new virus." Vaccination would be in the form of two injections three weeks apart [83].

The nurses' union CFE-CGC SNPI however, believes that mass immunization against influenza virus relatively Benin, this risk because a vaccine developed too quickly, and an adjuvant can trigger autoimmune diseases [ 84], [85].

The statement said the union, the H1N1 vaccine contains 10 times less antigen to accelerate production by the presence of the adjuvant AS03 (amplifier effect consisting of squalene and polysorbate). This adjuvant has never been used before in vaccine (excluding vaccine against anthrax during the Gulf War) might trigger immune reactions and especially increase the risk of serious side effects, such as Guillain - Barre [86] or the syndrome of the Gulf War [87].

It is also based on the presumption of significant toxicity of vaccines developed, as well as the concomitance of other incidents in early 2009 regarding the vaccine for seasonal flu, a complaint was filed Nice [88] September 23, 2009 with the prosecutor Eric de Montgolfier Mirella Carbonatto (SOS Justice and Human Rights). This followed a complaint filed June 10, 2009 in Austria and the United States by journalist Jane Burgermeister [89] who fears a malicious intent and had revealed the contamination of a large consignment of equipment vaccine (H3N2 strain) influenza virus H5N1 that had to withdraw the laboratory that Baxter had made in Austria [90] and which was destined for 16 countries of Central and Eastern Europe. A second complaint against X for "attempted poisoning of the population" was filed October 23 Isère at Grenoble [91]. A group of French applicants to complaints in connection with the vaccination of the influenza A H1N1 is therefore being created through the territory by the Nouvel Observateur and AFP that echo, a standard complaint being made available public with the reasons (mercantile aspect without regard for transparency or conditions of tender, serious and atypical in the manufacturing process of H1N1 and H3N2 vaccines in 2009, historical antecedents of harmfulness of products used, unconstitutional aspects. ..) and the relevant articles of law [92].
International Reactions
UN

Since reporting the first cases of influenza to the international community by the Mexican government, the United Nations (especially WHO) are in a state of permanent alert and reinforced. The secretary of the UN, Ban Ki-moonBan Ki-moon said at a press briefing at UN Headquarters [93] that "We are concerned that this virus could cause a new pandemic influenza. It could be in Benin his possessions as he could be potentially serious. "

He further noted that this disease will provide an opportunity to test the system response from the community of nations pandemic, established since 2007. Finally, he called for solidarity among nations, and particularly to poor nations especially vulnerable.
World Health

WHO is coordinating the global response to cases of influenza A (H1N1) and assesses the threat of a pandemic.

As of April 24, WHO published a daily newsletter [94].

The Emergency Committee (comprising fifteen international experts) held its second meeting April 27, 2009, at which have been examined has been decided to raise the...