Cow-to-Human Bird Flu Spread: 2nd Probable Human Case of H5N1 Avian Flu Linked to Outbreak Among Dairy Cows in the US

In a second probable case, a human bird flu case has been associated with the ongoing avian flu outbreak among dairy cows in the US.

The virus was first detected in US livestock earlier this year. Its presence has now been confirmed across 51 dairy herds within nine states.

2nd Probable Human Case of Bird Flu

The person was a farmworker from Michigan who was regularly exposed to infected livestock. The farmworker reportedly exhibited mild symptoms and has since recovered.

Following exposure to dairy cows carrying the infection, the person was monitored for symptoms. The person ended up developing pinkeye or conjunctivitis. An eye sample that was collected was found to test positive for the bird flu virus.

On the contrary, a sample collected from the person's nasal passage was found to test negative.

Dr. Nivah Shah, the principal deputy director of the Centers for Disease Control and Prevention, says that the negative test results of the nasal sample are quite reassuring. Dr. Shah explains that, though it does not eliminate possibilities, it reduces the chances of transmission through a respiratory route.

This case is also the second instance where a person ended up developing pink eye due to avian flu infection. This was also the only symptom experienced by the earlier Texas dairy worker, whose case was the first documented cow-to-human bird flu transmission on record.

The report by the CDC explains how avian flu exposure could lead to eye infections, which is still unknown. It is possible that they arise from the eye's contamination with some contaminated fluid or touching the eye with the virus contaminating one's hand.

The CDC is examining the virus' genetic data and will soon release the data. In the meantime, the agency still considers bird flu spread risk low.

Bird Flu Outbreak Among Dairy Cows

A bird flu subtype known as H5N1 was initially detected among dairy cows in the US in March. Since then, it has been found among cattle across nine different states.

Meat supply and commercial milk of dairy cows have been said to be safe for consumption. However, raw milk samples from infected cows were found to have the virus. Hence, unpasteurized milk could end up posing infection risks to humans.

Nevertheless, there have been no H5N1 human infections that have been associated with raw milk consumption.

The CDC has released some guidance for those who work with animals that are infected with H5N1 and those who could be exposed to the bird flu virus.

For one, it is important for people to avoid unprotected, long, or close exposures to animals that are dead and sick, such as cows, poultry, and wild birds.

It is also important to avoid unprotected exposure to the bedding, poop, closed materials, and unpasteurized milk of animals.

While H5N1 is known to be fatal for birds, this is not the case for humans. The virus could trigger a wide variety of symptoms, with possibilities ranging from being asymptomatic to fatal.

There have only been three human H5N1 infections reported in the US. All of the cases have been quite mild.

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