At this point, the risk to the public is quite low. Over 50 million people have attended fairs throughout the country, yet only 277 cases of H3N2v have been identified.
In making his case for closing the swine barns at the Minnesota State Fair ("This year, it seems, it's 'risk on' with swine flu," Aug. 26), Michael Osterholm begins by quoting Danish physicist Niels Bohr: "Prediction is very difficult, especially if it's about the future."
I couldn't agree more about predicting the future -- or with Osterholm's concern about swine flu. When the new H3N2v influenza strain began to be seen again this year in the United States, after making an initial appearance last year, we joined other public health and animal health experts throughout the country in reviewing the data on this illness.
We conferred as a public health community with the U.S. Centers for Disease Control and Prevention (CDC) regarding measures to control the spread of the virus.
This virus is associated with swine contact. There have been only rare occurrences of transmission of the virus from one person to another. According to CDC, the virus is related to human influenza viruses that circulated in the 1990s, so adults are thought to have some immunity against these viruses. That may account for the fact that most of the cases have occurred in children.
At this point, the risk to the public is quite low. Over 50 million people have attended fairs throughout the country, yet only 277 cases of H3N2v have been identified, and most of those have been among exhibitors. The severity of illness is similar to regular seasonal flu, and it appears that the rate of infection is decreasing.
As the date for the State Fair approached, we at the Minnesota Department of Health again consulted with CDC, the Minnesota Department of Agriculture, the Board of Animal Health, the University of Minnesota Veterinary Medicine Diagnostic Lab, and Osterholm. All, with the exception of Osterholm, concurred that the risk to the general population was low and agreed that exhibition of swine at the State Fair should be allowed.
We have worked closely with the State Fair to provide information about H3N2v, including signage that covers prevention measures and warnings for people at higher risk for flu complications. We ensured that the veterinarians inspecting animals at the fair and people exhibiting swine were aware of the situation. The U.S. Department of Health and Human Services has also taken early steps to make a vaccine against H3N2v in case the behavior of the virus changes and it becomes needed.
Osterholm notes that the threat of influenza dates back to the time of Hippocrates. As a physician and health commissioner, my pledge to "first do no harm" also dates back to Hippocrates.
Closure of swine exhibits at fair events is a very palpable and aggressive measure. Carried to its logical conclusion, this approach would require more than just closure of seasonal swine exhibits at fair events.It would also require substantial modification of many other activities involving contact between people and pigs.
The cost -- in terms of both economic impact and social disruption -- could be considerable. This is not a proportionate response to the theoretical threat of gene mutation that can't actually be quantified.
It should be noted that Minnesota has had at least five cases in recent years where swine influenza of different types infected people with no further spread.
Because influenza viruses have the capacity to change and become more transmissible, we take very seriously the concerns raised by Osterholm. We will monitor the situation and continue close communication with all of our public health and animal health partners.
In his dealings with students, Niels Bohr was always wary of becoming dogmatic. He once cautioned, "Every sentence I utter must be understood not as an affirmation but as a question." All of us who are dealing with the H3N2v virus need to embrace that perspective.
Influenza is a humbling disease that constantly challenges our medical and public health knowledge. Only by being open to the questions that it raises will we be able to maintain Minnesota's legacy of using science-based public health to effectively protect the health of all members of our community.
Dr. Edward P. Ehlinger is commissioner of the Minnesota Department of Health.