Unheard of new strain is hybrid resulting from a combination of four different viruses
Friday, April 24, 2009
The World Health Organization has warned that a new form of influenza that may have spread from Mexico into the U.S. could develop into a pandemic-type virus.
Hundreds of people in Mexico have been infected and 60 have died from suspected swine flu, while seven human cases have been confirmed in the United States, a World Health Organisation spokeswoman has said.
U.S. labs are still running tests on the Mexican strain of the virus, results of which will be released by the will be released later today by the federal Centers for Disease Control and Prevention in Atlanta.
At this point it is not yet clear whether the two strains are the same. Some media reports have failed to make this clear, while the Drudge report has jumped in head first declaring an “OUTBREAK” with a giant frothing red headline.
Five of the U.S. cases were recorded in California with a further two in Texas. The first two cases in Southern California appeared almost simultaneously, 100 miles apart, indicating that the virus can silently spread. Neither case was due to contact with swine, and family members had symptoms before and after the confirmed cases, indicating that the H1N1 swine flu is being efficiently transmitted human to human.
Most of the Mexican cases were found in healthy young adults with no known record of prior illness, according to reports.
Schools in Mexico City and the surrounding areas have been temporarily closed and people with flu symptoms have been advised to stay home from work. The Mexican government has launched a huge vaccination campaign.
A constantly updated map of the cases swine flu can be viewed here.
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The WHO has also pointed out that pigs have been implicated in the emergence of new influenza viruses responsible for two of the previous century’s influenza pandemics, including the 1918 pandemic strain which spread to nearly every part of the world killing an estimated 2.5 to 5% of the human population – somewhere in the region of 50 million to 100 million people.
The European Centre for Disease Prevention and Control has reiterated the WHO comments, writing on it’s website:
“The infection of humans with a novel influenza A virus infection of animal origins as has happened here is of concern because of the risk, albeit small, that this could represent the appearance of viruses with pandemic potential.”
According to scientists at the CDC, genetic analysis indicates that the virus is “highly unusual”:
“It is a hybrid that resulted from a combination of four different viruses — one that typically infects people, one that originated in North American birds and two from pigs in Europe and Asia,” Anne Schuchat, director of the CDC’s National Center for Immunization and Respiratory Diseases, told the Washington Post.
“The good news is all seven of these patients have recovered,” she said. The virus appears to be resistant to two drugs normally used to treat the flu, but two others appear to be effective against it.
“This combination has not been recognized before in the U.S. or elsewhere,” Schuchat said.
Other scientists have warned that if a pig is simultaneously infected with a human and an avian influenza virus, it can serve as a “mixing vessel” for the two viruses that could combine to create a new more virulent strain.
Though this story has broken in the mainstream media today, authorities have been tracking it for some time. One week ago, the Public Health Agency of Canada contacted health and quarantine services to inform them that Mexican health authorities had advised Canada to be on alert for possible infections.
This article was posted: Friday, April 24, 2009 at 10:06 am