Each year, the vaccine is made from three strains of the influenza virus that researchers suspect will be the most active.
The farmer "may have exposed swine on the farm to an influenza virus, " said Dr. Brian Evans of the Canadian Food Inspection Agency.
Though commonly known as "stomach flu, " it is not caused by the influenza virus, according to the U.S. Centers for Disease Control and Prevention.
This year's North American vaccine is made from three viruses: two types of influenza A virus (H3N2 and H1N1) and an influenza B virus.
In Chile and Australia, two countries with many flu cases, she said H1N1 appears to be the dominant strain, "crowding out" the seasonal influenza virus.
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According to Dr. Ron Fouchier, a Dutch virologist, this mutation allows the virus to reproduce at much lower temperatures than a standard avian influenza virus.
It is commonly known as "stomach flu, " but is not caused by the influenza virus, according to the U.S. Centers for Disease Control and Prevention.
All influenza vaccines are made by growing influenza virus particles in chicken eggs before treating them in a way to kill (inactivate) or weaken the viruses.
Person-to-person transmission is believed to occur in a manner similar to the spread of the influenza virus: through infected people coughing and sneezing, the CDC said.
But the monitoring of birds, pigs, people and the genetics of the influenza virus have all been stepped up in response to recent outbreaks of both swine flu and bird flu.
The technology, however, could be applied to other vaccines, such as those against influenza virus, or vaccines under development for TB and malaria or for existing vaccines administered in childhood.
It is caused by a type-A influenza virus.
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Since neither of the two children, a 10-year-old boy and a 9-year-old girl, had contact with pigs, it "increases the possibility that human-to-human transmission of this new influenza virus has occurred, " according to a CDC report.
The archaic technology for making them, which involves injecting influenza virus into chicken eggs and separating out the resulting antibodies, only allows for a few flu strains to be included and they must be picked far in advance.
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The reason for that is that the influenza virus has a rapid rate of mutation, forcing companies that manufacture the vaccine to make their best guess as to which flu types will be more prevalent in a given season.
Experiments in Germany tested 22 flavonoids on human lung cells infected with the H5N1 influenza A virus.
The virus that is contagious between humans does not yet exist (or it may just have come into being inside a young person in China who contacted both vH7N9 and a human influenza A virus to which they were not immune).
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During the pandemic, the H1N1 virus crowded out other influenza viruses to become the dominant virus.
Swine flu is a respiratory disease which is caused by a strain of the influenza type A virus known as H1N1.
Furthermore, although identifying the signs and symptoms of influenza in travellers can be an effective monitoring technique, it is not effective in reducing the spread of influenza as the virus can be transmitted from person to person before the onset of symptoms.
Two common gut bacteria, Escherichia coli and Helicobacter pylori, and also the influenza-A virus, are particularly adept at playing the evasive game of molecular mimicry, and the team is now looking at possible connections between different gut bacteria and autoantibodies against melanocortins to see if they can pin down which, if any, of these bugs might be responsible.
As of January 5, the CDC said Friday, the predominant virus in the United States was an influenza A (H3N2) virus that matched well with the H3N2 virus represented in the vaccine.
Unlike cold viruses, which have been tested in humans, influenza is a potentially deadly virus.
Mayo Clinic vaccine researcher Gregory Poland counts more than a dozen new diseases that have emerged in the last few decades: HIV, Lyme disease, West Nile virus, avian influenza.
The H7N9 strain has lead to the usual concerns about the virus causing a deadly influenza epidemic in China.
The children were infected with a virus known as swine influenza A H1N1, which has a unique combination of genes not previously seen in flu viruses in either humans or swine - although it shares similarities with a virus that has been circulating in pigs since 1999.
Essentially, they can detect up to eight viruses of various strands of influenza, including things like the H1N1 virus.
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We shouldn't be seeing this much influenza and it's with a new virus and that's the cause fo the concern.
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The World Health Organization declared the virus, also known as the novel influenza A(H1N1), a global pandemic June 11.
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