Colorado’s outbreak of avian flu in poultry and dairy cattle seems to have died down, though the state continues to monitor farms for signs of the virus. That doesn’t include regularly testing farms’ workers though — unless they have symptoms and their employers have a known outbreak. Dairies have to bulk-test their milk at least once a week for H5N1, a flu virus that is particularly lethal to poultry and spilled over to cattle earlier this year.