CDC study suggests agricultural fairs are a potential source for future epidemics

A new study conducted by scientists from the U.S. Centers for Disease Control and Prevention concluded that a 2011 H3N2 influenza A outbreak in Pennsylvania was caused by a reassortment of a swine flu virus with H1N1 influenza A.

In August 2011, a child who attended an agricultural fair in Pennsylvania was diagnosed with an H3N2 influenza A variant. The CDC study found that such fairs have the potential to be venues for the transmission of viruses between animals and humans and a possible point of origin for new epidemic.

The researchers suggest that public health officials investigate the outbreak of respiratory illnesses possibly linked to agricultural events.

After the first illness was identified, CDC investigators interviewed an agricultural club that attended the fair and then conducted a retrospective cohort study of its members, identifying 82 suspected, four probable and three confirmed cases of the strain.

The research revealed that among 127 members of the cohort study, the risk for suspected case status increased as their exposure to swine increased.

"Although the frequency of zoonotic influenza transmission at agricultural events is unknown, these events provide opportunities for swine influenza viruses to infect humans who have contact with infected swine," the authors wrote. "Human and swine influenza viruses may circulate at these events, creating opportunities for virus reassortment and the emergence of novel strains."