Influenza A H3N2v Detected in Michigan

September 4, 2013 — 

The Michigan Departments of Community Health (MDCH), and Agriculture and Rural Development (MDARD), along with the Berrien County Health Department (BCHD) have identified two cases of an H3N2 variant (H3N2v) associated with the Berrien County Youth Fair, which took place August 12-17, 2013. Both cases involved children attending the fair. At least one of the cases was a swine exhibitor at the fair.

In addition, a sick pig from the fair tested positive for Influenza A H3N2 at the National Veterinary Services Laboratories in Ames, Iowa. MDCH, MDARD, and BCHD are working with the Berrien County Youth Fair (BCYF) board to reach out to swine exhibitors who attended the fair to identify additional illnesses. As a precaution, Michigan public health agencies have conducted an extensive multi-state outreach to meat processing plants that were identified as being in receipt of live swine from the fair. These facilities have been made aware of the potential exposure to their employees, symptoms of illness, and given instruction on seeking care and testing. MDARD has notified managers at eight additional fairs scheduled to take place in the coming weeks, and asked them to reach out to swine exhibitors and the fair veterinarians about the H3N2v case and to use proper safety measures to prevent spreading illnesses.

Prior to this case, two human infections with influenza A (H3N2) variant (H3N2v) virus were reported to CDC during week 29 (Indiana [1] and Ohio [1]). A total of 18 H3N2v cases have been reported this summer. No deaths have occurred. At this time no ongoing human-to-human transmission has been identified and all cases have reported close contact with swine in the week prior to illness onset. Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases may be identified as the investigation continues.

For more information about H3N2v, visit http://www.cdc.gov/flu/swineflu/h3n2v-basics.htm.