Michigan reports H5 avian flu in dairy farm worker

dairy farm workers


The Michigan Department of Health and Human Services (MDHHS) today announced an H5 avian flu case in a Michigan farm worker who had regular exposure to infected livestock, marking the third human case in the United States and the second related to the H5N1 outbreaks in dairy cattle.

Patient recovered after mild symptoms

In a statement, MDHHS said the identification of the case came after the state's ongoing public health actions allowed farm workers to monitor and notify health officials if they develop symptoms.

Officials didn't detail the patient's symptoms, but said they were mild and that the farm worker has recovered. The earlier patient from a Texas farm also had a mild illness, which consisted of conjunctivitis.

Natasha Bagdasarian, MD, MPH, chief medical executive at the MDHHS, said, "Michigan has led a swift public health response, and we have been tracking this situation closely since influenza A (H5N1) was detected in poultry and dairy herds in Michigan. Farmworkers who have been exposed to impacted animals have been asked to report even mild symptoms, and testing for the virus has been made available."

CDC weighs in on test results and current risk

Also in a statement today, the Centers for Disease Control and Prevention (CDC) said a nasal swab for the worker tested negative for H5 influenza at the state lab in Michigan, but an eye swab shipped to the CDC for testing was positive, suggesting an eye infection, a symptom similar to the Texas patient. 

The CDC's lab is one of a few where can eye specimens can be used with the CDC's H5 test. The CDC also retested the nasal specimen, which was negative for the virus. Further subtyping is underway pending genetic sequencing.

Sequencing of the virus from the clinical specimen is underway and will be made available within 1 to 2 days if successful. Additional genetic analysis will look for any changes to the virus that could alter the agency’s risk assessment. For now, the CDC said the identification of a second case doesn't change its assessment that the risk to humans remains low.

At a media briefing today, Nirav Shah, JD, MD, the CDC's principal deputy director, praised Michigan's health department for its active monitoring of farm workers and its ability to work with and connect with farms. "They've led the way in helping us understand what's going on."

Michigan reports H5N1 in one more dairy herd

Michigan's agriculture department today reported another H5N1 avian flu outbreak in a dairy herd, bringing the number of affected farms in the state to 19.

In a statement, the Michigan Department of Agriculture and Rural Development (MDARD) said the newly detected outbreak in in Gratiot County. Samples tested positive for H5N1 at the Michigan State University Veterinary Diagnostic Laboratory and will be sent to the US Department of Agriculture (USDA) National Veterinary Services Laboratory for further confirmation.

The latest outbreak struck a facility in Gratiot County, where the virus was found at three other dairy farms earlier this week. Michigan has reported the most outbreaks of any state, with nine counties affected among 19 outbreaks. Five occurred in Gratiot County. 

In other developments, the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) reported one more dairy herd outbreak, which involves a farm in Texas, raising the national total to 52.

Editorial note: This story was updated at 3:53 CST to include comments from an HHS briefing and an update from the USDA.

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