# 7518
Although our attentions have been focused primarily on MERS-CoV and the emerging H7N9 avian virus in China, swine variant influenza viruses have been on the radar this summer as well.
Until about two years ago we rarely saw more than 3 or 4 human cases each year, but 2011 saw 12 cases reported, and last year (2012) more than 300 infections were recorded - mostly in Midwestern states, and nearly all associated with attendance at county and state fairs.
The H3N2v strain has been the most widely reported, with H1N1v and H1N2v far less common. Earlier this month we saw 12 cases reported in Indiana (see Indiana Reports 8 More H3N2v Cases).
On July 5th, the CDC released a HAN Advisory On H3N2v, alerting doctors to the possibility that more cases could turn up this summer.
With the county and state fair season well underway, earlier this month the CDC also released two new interim guidance documents on H3N2v for local public health agencies; one on case definitions, and the other on surveillance and specimen collection.
Today, the CDC’s FluView reports two more confirmed cases; one in Ohio and one in Indiana.
2012-2013 Influenza Season Week 29 ending July 20, 2013
All data are preliminary and may change as more reports are received.
Novel Influenza A Viruses:
Two new human infections with influenza A (H3N2) variant (H3N2v) virus were reported to CDC during week 29 (Indiana [1] and Ohio [1]). A total of 14 H3N2v cases have been reported this summer. No hospitalizations or deaths have occurred. At this time no ongoing human-to-human transmission has been identified and all 14 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.
Because of reporting schedules, state totals posted by CDC may not always be consistent with those reported by state health departments. If there is a discrepancy between state and CDC case counts, data from the state health department should be used as the most accurate number.
Early identification and investigation of human infections with novel influenza A viruses is critical in order to evaluate the extent of the outbreak and possible human-to-human transmission. Additional information on influenza in swine, variant influenza infection in humans, and strategies to interact safely with livestock can be found at http://www.cdc.gov/flu/swineflu/h3n2v-cases.htm.
It is likely (see CID Journal: Estimates Of Human Infection From H3N2v (Jul 2011-Apr 2012)) that the number of confirmed cases under-represents the total number of infections that occur each year.
For now, the threat to the public appears low, and we remain in a watchful waiting mode. But anytime a virus jumps species – as this one has - we are particularly attentive.
The CDC offers the following advice to fairgoers to help reduce their odds of contracting this virus:
Preventive Actions
CDC Recommendations For People At High Risk:
- If you are at high risk of serious flu complications and are going to a fair where pigs will be present, avoid pigs and swine barns at the fair. This includes children younger than 5 years, people 65 years and older, pregnant women, and people with certain long-term health conditions (like asthma, diabetes, heart disease, weakened immune systems, and neurological or neurodevelopmental conditions).
If you are not at high risk, take these precautions:
- Don’t take food or drink into pig areas; don’t eat, drink or put anything in your mouth in pig areas.
- Don’t take toys, pacifiers, cups, baby bottles, strollers, or similar items into pig areas.
- Wash your hands often with soap and running water before and after exposure to pigs. If soap and water are not available, use an alcohol-based hand rub.
- Avoid close contact with pigs that look or act ill.
- Take protective measures if you must come in contact with pigs that are known or suspected to be sick. This includes wearing personal protective equipment like protective clothing, gloves and masks that cover your mouth and nose when contact is required.
- To further reduce the risk of infection, minimize contact with pigs in the pig barn and arenas.