Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said that the recently identified swine flu, called G4, is "something to watch for."
Speaking to the Senate AID Committee hearing, Fauci said, "The Chinese, for the past week or two, have identified a virus, in the environment, that has not yet been shown to infect humans, but is exhibiting what which we call rearrangement capacity. "
Fauci explained that when several different strains of a virus simultaneously infect the same host, such as a pig, they can exchange genetic information.
"When they all mix and contain some of the elements that can make them susceptible to human transmission, there is always the possibility that you may have another outbreak of swine flu like the one we had in 2009," Fauci said.
Fauci said G4 is still in the examination stage: "It is not an immediate threat."
"But it is something that we must monitor exactly as we did in 2009 with the onset of swine flu," he said.
The G4 virus, which is genetically descended from the H1N1 swine flu that caused the 2009 pandemic, was described in a study published in the Proceedings of the National Academy of Sciences on Monday.
The present day: The World Health Organization confirmed in an email to CNN on Tuesday that agency officials are carefully reading the new data that has emerged about the swine flu virus.
"The Eurasian avian-type swine influenza virus is known to circulate in the Asian swine population and can infect humans sporadically. Twice a year during influenza vaccine composition meetings, the entire Information about viruses and the need for new vaccine candidate viruses are discussed. We will read the document carefully to understand what is new, "WHO spokesman Christian Lindmeier said in the email.