I’ve been to our local county fair twice this week with my daughter. Frankly, she goes for the carnival rides, but I make sure our visits involve at least a few trips to the barns so she can learn a bit about cattle, pigs, chickens, turkeys, etc., while were there. This year, a very nice young man invited her into his pigs’ pen for some one-on-one time with the animals. She thought it was a lot of fun, and I was thrilled that she got some experience with a species that is completely foreign to most "city kids."
Then, on the following day I received an e-mail regarding an outbreak of swine flu primarily in people who have had contact with pigs while attending agricultural fairs … arrg! Here’s some of the information from the official CDC Health Advisory.
Multiple infections with variant* influenza A (H3N2v) viruses have been identified in 3 states in recent weeks. From July 12 through August 3, 2012, 16 cases of H3N2v were reported and confirmed by CDC. This virus was first detected in humans in July 2011. It has also been isolated in U.S. swine in many U.S. states. Since July 12, 2011, there have been 29 cases of H3N2v virus infection, including the 16 cases occurring in the last three weeks. All 29 cases were infected with H3N2v viruses that contain the matrix (M) gene from the influenza A (H1N1)pdm09 virus. This M gene may confer increased transmissibility to and among humans, compared to other variant influenza viruses. All cases have been laboratory-confirmed at CDC. Each of the 16 cases identified since July 12, 2012, reported contact with swine prior to illness onset; in 15 cases, contact occurred while attending or exhibiting swine at an agricultural fair. While the viruses identified in these cases are genetically nearly identical, separate swine exposure events in each state were associated with human infections. There is no indication that the cases in different states are epidemiologically related.
Clinical characteristics of the 16 H3N2v recent cases have been generally consistent with signs and symptoms of seasonal influenza, and have included fever, cough, pharyngitis, myalgia, and headache. No hospitalizations or deaths have occurred among the 16 confirmed cases since July 2012. Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases are likely to be identified as the investigation continues.
Novel influenza A virus infection has been a nationally notifiable condition in the United States since 2007. Since that time, human infection with animal-origin influenza viruses has been rare, with ≤6 cases reported each year, until 2011 when 14 cases were identified. While most of the cases are thought to have been infected as a result of close contact with swine, limited human-to-human transmission of this virus was identified in some cases in 2011. Therefore, enhanced influenza surveillance is indicated, especially in regions and states with confirmed H3N2v cases.
Interim Recommendations for the Public
- Persons who are at high risk for influenza complications (e.g., underlying chronic medical conditions such as asthma, diabetes, heart disease, or neurological conditions, or who are pregnant or younger than 5 years, older than 65 years of age or have weakened immune systems) should consider avoiding exposure to pigs and swine barns this summer, especially if ill pigs have been identified.
- Persons engaging in activities that may involve swine contact, such as attending agricultural events or exhibiting swine, should wash their hands frequently with soap and running water before and after exposure to animals; avoid eating or drinking in animal areas; and avoid close contact with animals that look or act ill.
- Patients who experience influenza-like symptoms following direct or close contact with pigs and who seek medical care should inform their health care provider about the exposure.
- Patients with influenza-like illness who are at high risk for influenza complications (e.g., underlying chronic medical conditions such as asthma, diabetes, heart disease, or neurological conditions, or who are pregnant or younger than 5 years, older than 65 years of age or have weakened immune systems) should see their health care provider promptly to determine if treatment with antiviral medications is warranted.
I still encourage everyone to get out and enjoy their local agricultural fairs, especially those of you who have kids. Fairs are a great way to learn about an essential part of our community that is often taken for granted. Just stay informed about the outbreak and follow the CDC recommendations to keep yourself and your loved ones safe.
Dr. Jennifer Coates
Image: InavanHateren / via Shutterstock