Strain Of Swine Influenza Identified In Kansas County
A Riley County child has been infected with a strain of swine influenza not commonly seen in humans, but has fully recovered following a mild illness.
No other cases have been identified, but an investigation is underway.
The influenza strain that infected the child was identified as an H3N2 virus that commonly circulates in pigs in North America. It is different from the pandemic H1N1 virus, also of swine origin, that was first detected in the United States in mid-April.
“It is critical for people to understand that this H3N2 virus is not related to the pandemic H1N1 virus,” said Jason Eberhart-Phillips, Kansas State Health Officer and Director of Health at the Kansas Department of Health and Environment (KDHE). “This is not a mutation or a recombination of the pandemic strain, and it does not appear at this time to be a threat to human health.”
The child was likely exposed to the virus during the Riley County Fair in late July, where the child had direct contact with pigs. The child later developed influenza-like symptoms and sought medical care. The child has fully recovered and no other family members have reported illness.
KDHE is working closely with the Centers for Disease Control and Prevention (CDC), the U.S. Department of Agriculture (USDA), the Riley County Health Department and the Kansas Animal Health Department to investigate this case.
KDHE and the local health department are working to determine if the Riley County Fair swine exhibitors, or their pigs, have been ill.
Swine flu viruses do not normally infect humans, but human infections occur from time to time. Typically CDC has received reports of approximately one human infection with a swine influenza virus each year.
That number has risen slightly in the past few years. The increased number of reported cases this year is likely the result of increased influenza testing related to the H1N1 pandemic.
So far this year, 14 cases of human infections with swine influenza viruses have been reported in the United States. That number does not include the number of H1N1 cases, as the H1N1 virus has not been detected in swine in the U.S.
“Most instances of human infection with animal influenza viruses, like the swine H3N2 virus, do not result in human-to-human transmission,” Dr. Eberhart-Phillips said. “However, each case needs to be fully investigated to be sure that the viruses are not spreading among humans.”
Most commonly, cases of human infection with swine influenza occur in people with direct exposure to pigs, he added.