Ongoing occurrence Avian influenza The swine flu has caused mass deaths of poultry and wild birds in the United States and around the world. The virus, known as H5N1, is also adapting to mammals and has been found in cats, goats and raccoons. In the United States, at least 170 dairy farms in 13 states have been infected. In April, health officials confirmed that a dairy worker had contracted the virus from an infected cow, the first time the virus had been transmitted. Evolution from mammals to humans.
Currently, the number of people infected with avian influenza is on the rise. On July 25, the US Centers for Disease Control and Prevention announced Three new cases were confirmedThis brings the total number of cases in the United States since April to 13. The infected people were people who had direct contact with infected chickens at a Colorado poultry farm where an outbreak of the H5N1 virus had been reported among chickens. All three people experienced mild symptoms and have been prescribed the antiviral drug Tamiflu. The CDC says the risk of H5N1 infection in the general public remains low.
“These cases aren’t surprising at all, given that these people were handling infected poultry,” said Stephen Morse, an epidemiologist at Columbia University in New York. “The good news is, so far, there’s no evidence of person-to-person transmission. If that were to happen, we’d really have to raise our alert level to a red alert level.”
The CDC is investigating whether the Colorado workers were wearing personal protective equipment (PPE) such as gloves, coveralls, footwear, masks and goggles. Historically, most cases of avian flu have occurred in people who didn’t wear recommended PPE, according to the agency.
The new cases came on the heels of a new cluster of cases identified this month. On July 19, the CDC Six people were confirmed to be infected. Avian flu cases have been reported among poultry workers at another facility in Colorado. The infected workers were involved in culling birds infected with H5N1. When the virus is found on a farm, poultry producers must cull entire flocks. The three latest cases bring the number of confirmed cases of avian flu in Colorado to nine.
The remaining four cases (one in Texas, two in Michigan and one in Colorado) are linked to contact with infected dairy cows, where the virus likely spread to workers through raw milk. A study published in May They found that the virus could remain stable on milking equipment for at least an hour, increasing its potential to infect humans and other animals, but pasteurizing the milk killed the H5N1 virus.
So far this year, all U.S. cases have been mild, but in the past, the H5N1 virus has caused The mortality rate is about 50 percentFrom 2003 to 2023, a total of 878 people have tested positive for the virus, and 458 deaths have been reported.
The last time H5N1 caused a major outbreak among US poultry was in 2015. When 50.5 million birds become extinctThe first reported human case of avian flu in the United States was in a Colorado poultry worker in April 2022. No further cases have been reported until this year. “Something has changed,” says Annise Loewen, an influenza researcher at Emory University in Atlanta, Georgia. “Whether that’s due to a change in the virus or a change in transmission is hard to know without more information.”
