Bird flu detected in Colorado dairy cattle – a veterinarian explains the risks of the highly pathogenic bird flu virus

Highly pathogenic bird flu – also referred to as HPAI or bird flu – is present on a dairy farm in Colorado, the ninth state with confirmed cases. The U.S. Department of Agriculture's National Veterinary Services Laboratories confirmed the virus on April 25, 2024 in a herd in northeastern Colorado.

This farm is considered one of 35 dairy farms within the United States with confirmed cases of avian influenza in cattle as of May 7, 2024. the USDA.

Bird flu is nothing recent in Colorado. The state experienced an outbreak in poultry that began in 2022. Since then, the USDA has been Animal and Plant Health Inspection Service has reported that 6.3 million birds in nine business flocks and 25 backyard flocks are affected by the virus. The last discovery was in February 2024.

However, that is the primary time the disease has sickened cattle in Colorado.

I'm a veterinarian and epidemiologist at Colorado State University which focuses on infectious diseases in dairy cows. I served on a USDA incident management team for a few years and worked on several outbreaks of cattle and poultry diseases, and I’m leading the trouble at Colorado State University to analyze this novel outbreak.

The first cases of bird flu in cattle

Bird flu was first detected in dairy cattle in Texas and Kansas in March 2024.

Colorado State University faculty responded to the outbreak by forming a federal group with state departments of agriculture, the USDA and other universities to achieve a greater understanding of how this virus is transmitted between farms and between cows. The team coordinates the sampling and examination of sick and healthy cows on affected farms to know which animals are involved to eliminate the virusmeaning they usually tend to spread the disease and for a way long.

We are also working to seek out measures to contain this disease. Our network of animal health specialists works with dairy producers and provides them with weekly updates on recent data.

Detecting bird flu in cattle

In February 2024, Veterinarians and researchers began testing the blood, urine, feces, milk and nasal swab samples from sick cows. The virus was mostly detected in raw milk, suggesting the disease can have been transmitted to other cows through the milking process.

Recent laboratory tests have also detected the virus within the nasal secretions of cows for a short while before the virus appears of their raw milk.

At the tip of April, the US Food and Drug Administration and the USDA began testing business milk samples. So far, authorities haven’t discovered any live viruses in these samples.

This is to be expected resulting from the pasteurization process heats milk heated to at the least 161 degrees Fahrenheit (72 degrees Celsius) for at the least 15 seconds, kills the virus. The pasteurization times and temperatures utilized in the United States are intended to kill bacterial pathogens, but are effective against this virus.

Raw milk, because the name suggests, just isn’t pasteurized. The CDC linked Drink raw milk to many foodborne illnesses, including E. coli and salmonella. The presence of the virus that causes H5N1 bird flu, is one other cause for concern.

Milk producers are obliged to redirect abnormal milk and milk from sick cows from the food supply to guard consumers.

In addition to take advantage of, that’s USDA Food Safety and Inspection Service tested samples of business ground beef from states with sick cows. As of May 1, 2024, no virus has been present in beef.

Slowing the spread of the disease

At this early stage of the outbreak in dairy cows, researchers don't know exactly how bird flu spreads in cattle. Therefore, mitigation recommendations may change as more evidence is gained.

I even have seen many infected cows and so they looked dull and depressed, just like how humans feel during a viral infection. Many infected cows show symptoms just like those with flu, comparable to fever.

Many dairy producers separate sick cows from healthy cows in hospital stalls in order that sick cows might be easily monitored and treated.

There is the virus present in nasal secretions In the early stages of infection, it is feasible that the herd drinking water tanks could also be a source of infection. As a best practice, farmers should proceed to scrub these tanks at the least weekly – and much more continuously in hospital stables.

Infected cows can get better

The excellent news is that the majority cows are doing higher. Like an individual with the flu, they react to anti-inflammatory medications and oral fluids.

A small percentage of cows develop secondary bacterial infections and die or are humanely euthanized. Some cows get better from the infection but stop producing milk and are faraway from the herd and frequently slaughtered for meat.

Since the virus is most frequently detected within the milk of sick cows, our team recommends that milk producers proceed to follow the measures Best milking practices on the dairy farm, including disinfection of the cows' teats before and after milking, even for healthy cows.

Only one case of human conjunctivitis resulting from bird flu was reported in a 12 months Texas dairy farmer End of March. The employee was likely exposed through direct contact with milk from an infected cow or by rubbing eyes with hands or gloves that had come into contact with contaminated milk. The CDC recommends farm staff Wear personal protective equipment, including eye protection, when in direct or close physical contact with raw milk.

How dairy producers can protect their herds

Viruses can enter farms through the movement of cattle, people, vehicles, equipment and wild birds.

The US dairy industry has one Safe milk supply plan which deals with foreign and emerging dairy cattle diseases comparable to bird flu. The plan calls for increased biosecurity practices on farms during disease outbreaks.

Biosecurity practices include limiting livestock movements on and off farms, allowing only essential personnel to access cattle, stopping vehicles and equipment from other farms from entering cattle areas, and cleansing and disinfecting vehicles entering dairy farms. and drive out. Adherence to those practices should significantly reduce the potential of the virus entering recent herds.

Birds also transmit the virus. Because of their quick access to feed and water on dairy farms, they’re harder to manage. State and federal fish and game departments and Wildlife agencies work with farmers to scale back the danger of disease spread by wild birds. These include programs to limit the variety of birds drawn to dairy farms while respecting regulations to guard these species.

Producers observing cows with clinical signs of avian influenza should inform their veterinarians in order that proper testing might be performed to verify the presence of avian influenza. If a test result’s positive, the laboratory performing the test must report it to the USDA. As the USDA and affected states proceed to trace the disease, an accurate estimate of affected farms will allow investigators to find out how the virus is spreading from farm to farm—and whether we’re making progress toward containment.

image credit : theconversation.com