(Radio Iowa) – Iowa Agriculture Secretary Mike Naig says bird flu has been confirmed in two more sites in the state.

Bird flu has been confirmed at a commercial site in Cherokee County with 88-thousand turkeys and at an egg-laying facility in Osceola County with five-point-three MILLION hens. Naig says nearly 13 million poultry animals have been killed in Iowa so far to try to prevent the spread of bird flu.

Naig says in the bird flu outbreak of 2015, the virus spread from facility to facility, but it appears bio-security measures at large operations are working — and officials believe this year’s round of bird flu is being spread by the spring migration of wild birds.

The bird flu outbreak in 2015 started in mid-April, but the first case of bird flu this year was confirmed on March 2nd. Naig says there’s still a steady supply of eggs, chicken and turkey in grocery stores, but it appears to be shrinking a bit.

Naig made his comments during taping of “Iowa Press” which airs tonight (Friday) at 7:30 on Iowa P-B-S.