Avian flu appears to have spread from a dairy farm in Colorado to a nearby chicken farm, infecting five workers tasked with eradicating infected birds.
Highly infectious viruses are Avian influenza H5N1has the potential to cause a pandemic, and the race is on to develop a vaccine to limit its devastating effects.
Centers for Disease Control and Prevention (CDC) Four human infections confirmed This occurred at a commercial egg production operation. The fifth case is awaiting confirmation from the CDC but is currently presumptive.
At present, there is insufficient evidence to determine the source and route of infection on the poultry farm, but it is speculated that the virus may have been transmitted from dairy cows to the poultry farm.
“Genomic sequencing of samples taken from the poultry farm confirmed that it is the same genotype of highly pathogenic avian influenza found in a nearby dairy flock,” said Eric Deeble, acting senior adviser to the Department of Health. United States Department of Agriculture He said at a press conference on Tuesday. Recorder CBS journalist Alexander Ting.
Although this is not sufficient to track the virus’s movement between species, it does suggest that the virus has the ability to thrive in a variety of animal hosts without significant mutations.
This possibility has scientists very concerned: the more species a virus can infect, the more efficiently it can spread. The first cow in the United States was infected with avian flu earlier this year, and the virus has since been transmitted to two humans.
“CDC’s risk assessment for the general population remains low, and CDC is not changing its recommendations,” said CDC Deputy Director Nirav Shah. He said at a press conference.
“For example, CDC does not recommend H5-specific vaccination for livestock workers because symptoms observed so far have been mild and because there have been no changes in the genetic structure of the virus that would suggest an increased risk to humans.”
He said preliminary analysis of the virus’s genome from one of the patients at the infected poultry farm had not shown any mutations that were of concern.
“This sequence is very closely related to two sequences from infected chickens on the farm where the worker may have been infected,” Shah said. Said.
“In addition, one of the virus subunits was 100% identical to the one in Texas and the first human case in Michigan.”
So far, symptoms in humans appear to be mild and recovery is quick, but the bigger concern is the impact this could have on agriculture.
Milk from infected cows becomes undrinkable and they are forced to be culled to prevent further spread, dealing a major blow to livestock populations, such as the 1.8 million chickens currently affected at a Colorado farm.
This culling appears to put humans at increased risk of infection: Five of the infected workers were employees who worked on placing the birds in carbon dioxide gas chambers for the culling process, according to the Colorado Department of Public Health and Environment. Reports.
“The large industrial fans certainly helped keep the barn cool, but the fans also spread things like feathers that are known to carry the virus around,” Shah said. Said.
“Furthermore, the control method used here requires workers to move from bird to bird, increasing the degree of contact with each potentially infected bird.”
PPE for this unpleasant job would typically be extensive, but workers likely struggled to maintain those precautions as temperatures in Colorado soared to at least 40°C (104°F) that day, Shah said. He said in a briefing.
An industrial hygienist was hired to research more effective infection prevention measures.
