DENVER — Three Colorado poultry workers at a commercial egg-laying facility in northeastern Colorado have tested positive for presumptive avian influenza, state health officials said Friday, underscoring the need to control a virus that has already killed more than 6 million birds and is now infecting dairy cows across the state.
The three additional cases, which have not yet been confirmed by the U.S. Centers for Disease Control and Prevention (CDC), would mean that Colorado not only leads the nation in the number of bird flu outbreaks among dairy cows, but more importantly, in the number of people infected with the H5N1 virus.
If confirmed by the CDC, the three additional cases would mean Colorado has now detected five cases of H5N1 among poultry and dairy workers since the highly pathogenic avian influenza outbreak was first detected in the state in March 2022.
In a statement released Friday night, a spokesperson for the Colorado Department of Public Health and Environment (CDPHE) said the workers were slaughtering poultry at a farm in northeastern Colorado and were experiencing mild symptoms, including conjunctivitis or pink eye, as well as “common symptoms of respiratory infection.” The CDPHE statement did not specify what those respiratory symptoms were and did not say whether antiviral treatment had been given to the workers who tested positive for the virus. Denver7 was unable to reach anyone from the department by phone or email Friday night to respond to those questions.
None of the people affected were hospitalized, the spokesperson said in the statement.
“These preliminary findings further underscore the risk of exposure to infected animals,” a CDC spokesperson said in a statement. “There is no evidence of an unexpected increase in influenza activity in Colorado or other states experiencing outbreaks of H5 avian influenza in cows and poultry.”
The statement continued: “Human infections with this novel influenza virus (and others) are concerning because of their potential to cause severe illness. The other reason these types of human infections are concerning is their pandemic potential. If these viruses were to evolve to spread easily from person to person, it could trigger a pandemic.”
CDPHE was first notified of symptomatic workers at the poultry farm on Thursday and tested seven people. On Friday, CDPHE returned to the site with a larger team and tested 48 more symptomatic workers, a spokesperson said in an email to Denver7 late Friday. “Test results from samples collected today (July 12) are still pending,” the spokesperson added, noting that those samples will be tested this weekend.
“State epidemiologists suspect the poultry worker cases are the result of working directly with infected poultry. The investigation is ongoing with support from the CDC,” the CDPHE statement said.
The potential cases are linked to an outbreak of avian influenza at a Weld County egg-laying farm, where 1.8 million chickens had to be culled, according to CDPHE.
Following an outbreak at a Weld County egg-laying operation, a quarantine order is now in effect in parts of Weld County to limit the movement of birds in and out of the area, and commercial or backyard poultry owners in the quarantine area have been asked to report the status of their flock via this online form.
The CDC is sending a team to Colorado to support its investigation, the CDC spokesperson said, which will include “reviewing compliance with recommended use of personal protective equipment.”
How can I protect myself against bird flu?
State health officials maintain that the risk of catching bird flu to the general public is low, although people who come into contact with sick poultry or livestock are at higher risk of becoming infected with the virus.
So far, no human-to-human transmission of bird flu has been detected, according to the CDC.
The nation’s top public health agency recommends that farm workers who come into contact with livestock suspected or confirmed to be infected with the H5N1 virus wear disposable fluid-resistant coveralls, disposable gloves, boots or boot covers, vented safety glasses or a face shield, and an N95 respirator.
The general public should avoid contact with sick birds or other animals to reduce their risk of becoming infected with avian flu, state epidemiologist Dr. Rachel Herlihy has said in the past. If you must handle sick or dead birds or animals, be sure to wear gloves, a high-quality mask such as a KN95 or N95 respirator, and eye protection. After handling the animal, double-bag it and dispose of it in your municipal trash before washing your hands thoroughly with soap and warm water. If soap and water are not available, use an alcohol-based hand sanitizer, the CDC recommends.
People should also avoid unprotected exposure to animal feces, bedding, unpasteurized milk or materials that have been touched by, or near, birds or other animals suspected or confirmed to be infected with the H5N1 virus, CDC officials said.
CDPHE advises anyone who works with dairy or poultry and may have flu symptoms to call the state health department at 303-692-2700 (after hours: 303-370-9395). Officials said the department can help people who may have been exposed get tested for the flu and get medication if needed.
Can I get bird flu from drinking milk or eating meat?
FDA officials said the likelihood of eggs containing H5N1 is low “because of existing safeguards, including flock testing and federal inspection programs,” which require the disposal of infected eggs and poultry meat. Proper storage and preparation of eggs “further reduce the risk,” they said.
Although the agency “does not currently know whether HPAI H5N1 can be transmitted to humans through consumption of raw milk and products made from raw milk from infected cows,” scientists advise people to avoid raw milk and dairy products made from raw milk because they do not go through the pasteurization process, which inactivates harmful viruses and bacteria.
While Colorado does not test pigs and beef cattle for bird flu, ground beef appears to be safe to eat after USDA researchers found no live virus in samples of retail meat sold in states with ongoing outbreaks. The agency said it was confident the meat supply was safe after at least three separate safety studies found no virus particles in beef cattle, including one in which the meat had been cooked to varying degrees of doneness.
As of July 4, CDPHE was monitoring more than 500 dairy workers for possible exposure to bird flu. Nearly 70 people in Colorado have been tested for possible exposure to H5N1 after coming into contact with infected birds or livestock since March, the CDPHE spokesperson said.
Police declare state of emergency after bird flu outbreak at Weld County commercial egg plant
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