• A "highly pathogenic" strain of the H5N1 avian flu has been reported in China's Hunan province, China's Ministry of Agriculture and Rural Affairs said. 
• According to a report from Reuters 4,500 chickens died on the farm where the outbreak occurred.
• The government culled nearly 18,000 chickens as a result of the outbreak. 
• Whether a strain of avian flu is deemed "highly pathogenic" relates to its ability to kill chickens, according to USGS. 
• The World Health Organization says that while human cases of H5N1 can occur, it "does not infect humans easily."
• Visit Business Insider's homepage for more stories.

A "highly pathogenic" strain of the H5N1 bird flu has been reported in China's Hunan province, Chinese officials said, according to a Saturday report from Reuters. 

The outbreak was reported on a farm in the city of Shaoyang in the Hunan province, according to China's Ministry of Agriculture and Rural Affairs. Of the 7,850 chickens on the farm where the outbreak occurred, 4,500 died of the H5N1 avian flu, Reuters reported.

The Chinese government said it culled 17,828 chickens as a result of the H5N1 outbreak, per Reuters. 

Per the United States Geological Survey, the bird flu is deemed "high pathogenic" based on its ability to kill birds. 

"The designation of low or highly pathogenic avian influenza refers to the potential for these viruses to kill chickens," the USGS website says. "The designation of "low pathogenic" or "highly pathogenic" does not refer to how infectious the viruses may be to humans, other mammals, or other species of birds."

The USGS noted, however, that most strains of the bird flu are not highly pathogenic and cause "few signs of disease in infected wild birds."

"However, in poultry, some low-pathogenic strains can mutate into highly pathogenic avian influenza strains that cause a contagious and severe illness among poultry and sometimes wild birds, and often death," the USGS added. 

According to the World Health Organization, while H5N1 can be transmitted to humans, typically through contact with dead birds or a contaminated environment, it is rare in humans. 

"The virus does not infect humans easily, and spread from person to person appears to be unusual," the WHO said. "There is no evidence that the disease can be spread to people through properly prepared and thoroughly cooked food." The mortality rate in humans is 60%, the WHO added.

The news comes as the Wuhan coronavirus, which is believed to have originated from a bat in the Hubei province, which is North of Hunan, continues to spread throughout the country and has caused more than 259 human deaths and infected around 12,000 people. 

Read more: 

Scientists have published over 50 studies on Wuhan coronavirus in the last 3 weeks. They learned that 75,800 people in Wuhan could be infected.

A coronavirus case has been confirmed in the San Francisco Bay Area near Silicon Valley — a man who recently returned from Wuhan and Shanghai

The US just confirmed its 7th coronavirus case: a man in the San Francisco Bay Area. Here's what we know about all the US patients.

This app has all the up-to-date information you need to know about the Wuhan coronavirus