Worst bird flu in US history led to nearly 58 million poultry deaths

The H5N1 strain of the virus is troublesome since it has found a way to survive in wild birds and migrate to different parts of the world. As with viral infections, experts suggest that the virus be allowed to run its course. However, H5N1 has become more virulent over the years, and a single infected bird can spread the virus to up to 100 others.

Impact of the current outbreak

Since the outbreak in March 2022, the virus has claimed nearly four million poultry in the state of South Dakota, while Nebraska has lost 6.7 million poultry, up from the 4.8 million poultry death during an outbreak in 2015, the WSJ said in its report. In Colorado, 6.25 million poultry have died. To prevent the virus from spreading, entire flocks are destroyed after an infection is confirmed. As per data from the U.S. Department of Agriculture, the virus has caused the deaths of nearly 58 million poultry across 47 states in the U.S.

The flu is currently peaking in Japan, where the agricultural ministry is planning on culling ten million chickens that are at risk of having been exposed to the virus, a France24 report said. In Europe, more than 2,500 outbreaks have been reported across 37 countries, and more than 50 million birds have been culled so far.

In the past, outbreaks have slowed down during warmer months but did not show signs of stopping last year. Rather, the epidemic seems to be picking up, with as much as 35 percent higher infections seen in autumn 2022.

Impact on other animals

Generally speaking, viruses infect only one host species and do not cross over to others. However, since they mutate very rapidly, a virus can jump over and infect another species, as we saw in the case of the COVID-19 pandemic.

In the case of H5N1, too, the virus has been largely infecting birds, both captive and in the wild. Apart from poultry, the virus has been found to be responsible for the deaths of migratory birds such as the Great Skuas, gannets, gulls, geese, and even eagles in Scotland.

The virus has also traveled to infect penguins in South Africa, dalmatian pelicans in the Balkans, and cranes in Israel. In the U.S., though, three grizzly bears contracted the virus, the first such reported case, and were euthanized in Montana, officials said.

When the H5N1 strain broke out, humans were also infected and had high fatality rates. However, over the years, the strain has evolved to infect humans lesser, and the risk of a pandemic in humans remains low until the virus mutates rapidly to infect humans too.