Researchers find powerful swine flu strain in Korea

September 10, 2012 by Barbara Bronson Gray, Healthday Reporter
Researchers find powerful swine flu strain in korea
While unlikely to spread to humans, scientists call for close global surveillance of pigs.

(HealthDay)—A new report shows that a deadly swine flu virus can infect ferrets, highlighting the importance of continuous surveillance of emerging flu strains.

Scientists in South Korea, working closely with researchers in the United States, found that a particular , common among pigs and known as Sw/1204, caused death within 10 days of inoculation in ferrets. The virus is also transmittable by respiratory droplets, through coughing or sneezing, making it potentially highly contagious.

Ferrets are considered the best for studying the flu because they're susceptible to the same as are humans and show similar symptoms.

Should people start to worry?

"This is not a run-for-the-hills situation," explained study co-author Richard Webby, director of the Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds at St. Jude Children's Research Hospital, in Memphis. "The study adds value to our surveillance and helps us better prioritize our ."

, endemic among pigs worldwide, can be transferred between pigs, birds and humans. Pigs are considered "genetic mixing vessels," which means they're great at brewing new and potentially dangerous viruses.

The study authors say the findings show the pandemic potential of the TRSw that the researchers isolated from Korean pig slaughterhouses. TRSw viruses are Korean "triple-reassortant swine" H1N2 and H3N2, genetically related to strains seen in North America. "Triple" viruses, first detected in 1998 in the United States, were found to have genetic segments from swine, human and bird viruses. Sw/1204 is one of these "triple" viruses.

The researchers used a process called reverse genetics, which allows them to manipulate the virus' genome to better understand its and transmissibility.

The study pinpointed two specific mutations of the virus responsible for its virulence that have been suspected but not previously proven, said Nancy Cox, director of the influenza division at the U.S. Centers for Disease Control and Prevention. "These viruses were already on our radar screen," she explained.

Cox said that it's rare that these particular viruses affect humans, though they can. "Is this virus with these two mutations likely to infect pigs, and then infect people, causing a widespread pandemic? Because there's a lot of immunity in pigs to these viruses, it's unlikely to infect humans," she explained.

Dr. Bruce Hirsch, attending physician in infectious disease at North Shore University Hospital in Manhasset, N.Y., said one of the direct benefits of the study is that the virus' "genetic signature can now be used in surveillance studies" to help researchers identify potential risks.

"Flu is a real threat, very, very dynamic and continuing to evolve and to change," said Hirsch. "We need to understand what's out there and whether it can affect our health."

Webby advises people to get the flu vaccine this fall. "While we're not concerned that this virus is spreading, the vaccine helps protect against some viruses circulating in swine."

Explore further: Flu cases from county fair traced to pigs

More information: "Virulence and transmissibility of H1N2 influenza virus in ferrets imply the continuing threat of triple-reassortant swine viruses," by Philippe Noriel Q. Pascua et al. PNAS, 2012.

Learn more about seasonal flu from the U.S. Centers for Disease Control and Prevention.

Related Stories

Flu cases from county fair traced to pigs

July 26, 2012
(HealthDay) -- Four people attending an Indiana county fair this month came down with flu traced to pigs, U.S. health officials report.

CDC preparing vaccine for new swine flu

August 4, 2012
(HealthDay) -- Only 29 human cases of a new strain of "swine" flu have been identified in two years, but the U.S. Centers for Disease Control and Prevention is making sure it's prepared should the H3N2 strain become more ...

Long-term study of swine flu viruses shows increasing viral diversity

May 25, 2011
Increased transportation of live pigs appears to have driven an increase in the diversity of swine influenza viruses found in the animals in Hong Kong over the last three decades, according to a new study.

Recommended for you

Gastric acid suppressant lansoprazole may target tuberculosis

November 21, 2017
A cheap and widely used drug, used to treat conditions such as heartburn, gastritis and ulcers, could work against the bacteria that cause tuberculosis (TB), according to new research from UCL and the London School of Hygiene ...

Improving prediction accuracy of Crohn's disease based on repeated fecal sampling

November 21, 2017
Researchers at the University of California San Diego Center for Microbiome Innovation (CMI) have found that sampling the gut microbiome over time can provide insights that are not available with a single time point. The ...

Anti-malaria drug shows promise as Zika virus treatment

November 17, 2017
A new collaborative study led by researchers at Sanford Burnham Prebys Medical Discovery Institute (SBP) and UC San Diego School of Medicine has found that a medication used to prevent and treat malaria may also be effective ...

Decrease in sunshine, increase in Rickets

November 17, 2017
A University of Toronto student and professor have teamed up to discover that Britain's increasing cloudiness during the summer could be an important reason for the mysterious increase in Rickets among British children over ...

Scientists identify biomarkers that indicate likelihood of survival in infected patients

November 17, 2017
Scientists have identified a set of biomarkers that indicate which patients infected with the Ebola virus are most at risk of dying from the disease.

Research team unlocks secrets of Ebola

November 16, 2017
In a comprehensive and complex molecular study of blood samples from Ebola patients in Sierra Leone, published today (Nov. 16, 2017) in Cell Host and Microbe, a scientific team led by the University of Wisconsin-Madison has ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.