July 12 (Reuters) – Colorado has reported three presumptive cases of H5 bird flu virus infection in poultry workers, according to the Centers for Disease Control and Prevention (CDC) on Friday.
The three workers, who were involved in culling infected birds at a poultry facility experiencing an H5N1 outbreak, exhibited mild symptoms such as conjunctivitis (pink eye) and common respiratory infection symptoms. None of the workers required hospitalization, state health officials confirmed.
State epidemiologists believe the infections resulted from direct contact with infected poultry. The CDC has dispatched a team to Colorado to aid in the investigation, emphasizing that the risk to the general public remains low.
“Human infections with H5N1 avian flu are concerning due to the potential for severe disease and the possibility of a pandemic if the virus evolves to spread easily between people,” the CDC stated.
The current cases are part of a global H5N1 bird flu outbreak affecting wild birds, poultry, and various mammals. An outbreak in U.S. dairy cows has also been reported. Preliminary tests by Colorado officials identified a novel influenza type in the workers, and samples have been sent to the CDC for confirmation.
If confirmed, these would be the fourth bird flu cases in Colorado and the seventh in the U.S. since March. The CDC’s investigation will determine if updates to current guidance are necessary and if a change in the risk assessment is warranted.
The CDC reiterated its recommendations to avoid close, prolonged, or unprotected exposure to sick or dead animals, including wild birds, poultry, and other domesticated or wild animals. Precautions should also be taken to avoid exposure to animal feces, litter, unpasteurized milk, or materials that have been in contact with animals suspected or confirmed to have bird flu.
The Colorado Department of Public Health and Environment confirmed that three farmworkers in northeast Colorado, who were culling infected birds, have preliminarily tested positive for H5N1. These workers showed mild symptoms and were not hospitalized. Their test results are pending confirmation from the CDC.
To date, four farmworkers in the U.S. have been infected with H5N1, with cases in Colorado, Texas, and Michigan. All cases involved direct exposure to infected animals, primarily dairy cows. Health officials maintain that there is no evidence of easy human-to-human transmission of H5N1.
The CDC has sent a team to Colorado to investigate the protective measures used by the workers, including personal protective equipment such as masks, safety goggles, and gloves.
The ongoing H5N1 outbreak, first identified in 1996 in China, has rapidly spread globally since a new strain surfaced in Europe in 2020. In the U.S., it has affected over 99 million birds and has also been found in various mammals, including marine mammals, skunks, squirrels, and domestic cats.
The CDC continues to monitor the situation and advises the public to exercise caution around potentially infected animals and materials.
