Last year, more than 57 million birds, including poultry, perished in the U.S. from a surge of avian influenza (H5N1), a killer disease that has been increasingly effective in attacking wild birds, especially migrating waterfowl. Mallards and Canada geese seem to be the most susceptible. The disease, which has flared up sporadically since its discovery, as fowl plague, in 1878, is caused by infections that occur naturally in wild aquatic birds. These infections are transmitted to other birds, domestic and wild, through bodily discharges as well as through contact with contaminated surfaces.
Until last summer, Avian Flu has been seasonal, proliferating from September to March and then disappearing during the warmer months. The current outbreak, however, has not fallen off over the last two summers.
The last major outbreak, in 2014-15, killed an estimated record 50.5 million birds in 21 states. Last year the disease, which was first detected at the end of 2021, popped up in nearly every state, with the morbidity count increased proportionally.
Avian flu does not affect all types of birds equally. While waterfowl and wild birds often carry and transmit the disease, they rarely get sick and die from it; raptors, on the other hand, are highly susceptible, and domestic poultry not only pick it up quickly but spread it immediately to their entire flock, leading to an almost 100 percent mortality rate. Of course, these little cluckers also spread it easily to their barnyard neighbors—geese, ducks, ostriches and turkeys.
Huge numbers of poultry—44 million laying hens, in fact—have perished or been culled since early 2022. Egg prices have shot up and grocery stores have limited the amount of eggs per customer.
Now there are signs the morbidity count is going down in the commercial egg-laying facilities, signaling a possible letting up of the current epidemic. Egg supplies most probably will remain constrained until spring; it takes three to four months to get back to peak productivity, 24 eggs per month per hen, after the facilities have been sanitized and re-stocked.
Avian flu is not a severe threat to humans. Although a small number of people have contracted it in the past (the 2022 flu has stricken one person, last April, in Colorado), the disease has never shown any propensity to transmit between people. The symptoms are mild and flu-like, and the worst-case scenario is pneumonia. The best possible defense is to not handle any stricken or dead bird, and to wear protective clothing and use a lot of soap and water if such handling is necessary.
As for the lucky songbirds, they are at low risk of exposure to or transmission of H5N1, and therefore they should still be allowed to visit their usual bird feeders, which should be regularly cleaned. Since last January, the United States Department of Agriculture has discovered the strain in 5,552 wild birds, and in a mere 63 songbirds. It has been found in 251 birds in New York, not one of which was in Otsego County, though a bald eagle was lost in Schoharie.
Avian flu will not likely disappear in the foreseeable future, and it will remain a threat to wildlife and domestic birds, but its spread and death toll are manageable. The Easter bunny should be pleased.