August 14, 2012 (TSR) – United States Center for Disease Control and Prevention is warning that a new strain of swine flu is raising concerns as it continues to infect people throughout the Midwest region.
CDC officials say that they do not expect an outbreak of the swine flu, adding that they do expect additional cases to occur. Officials noted that nearly 200 cases of the strain have already been identified.
“This is not a pandemic situation,” said Dr. Joseph Bresee of the Centers for Disease Control and Prevention.
The CDC says it expects the case count to increase, although they note that the current strain does not seem to impact humans nearly to the same extent as previous strains. Two people have already been hospitalized, but both have been released, officials said in a statement released Thursday.
While CDC officials downplayed concerns, state agencies across the upper Midwest are reportedly already preparing for the spreading flu strain.
Dr. Joseph Bresee, an epidemiologist in the CDC’s Influenza Division, said that there has been a predominance of cases in children and young adults and that all of the cases have been associated with close or indirect exposure to swine, often at state or county fairs. The other pig-to-human transmissions occurred in farmers or veterinarians.
“This time of the year is the time when you have fairs around the country … thousands of them,” Bresee said. “That accounts for the increased transmission more than anything else.”
The latest news comes as the CDC announced its plan to begin developing a new vaccine for the 2012 year. While only 29 human cases of a new strain of “swine” flu have been identified in two years, the CDC said it is making sure it’s prepared should the H3N2 strain become more widespread.
“This virus is still principally a swine virus, but it doesn’t seem to have onward spread. It’s still not a human virus,” Dr. Joseph Bresee, from the CDC’s influenza division, stressed during a noon press conference Friday.
“Even so, a H3N2 candidate vaccine has been prepared and clinical trials are being planned for this year,” he said.
The CDC is concerned about this particular virus is that it contains an element seen in the pandemic 2009 swine flu strain, H1N1, which may make it more likely for the virus to spread from person-to-person, say scientists. All 29 cases were infected with strains of H3N2 “that contained the matrix (m) gene from the influenza A H1N1 pandemic virus,” officials explain.
“This ‘m’ gene may confer increased transmissibility to and among humans, compared with other variant influenzas viruses.”
When a new flu virus pops up, “we immediately begin to think about the process of making a vaccine,” Bresee noted.
The incremental process involves finding a good vaccine candidate, reassessing and testing the virus, developing seed vaccines and ensuring their safety. The goal is to have a vaccine quickly available in case a pandemic occurs, as with H1N1 in 2009.
CDC officials say they are not equating this new H3N2 flu with the 2009 flu, but a new H3N2 vaccine is in the early stages of development and clinical trials are expected later this year.