Avian Flu Outbreaks Raise Concerns About Possible Pandemic

— -- An avian flu outbreak in the U.K. is just the latest to erupt across the globe, worrying health experts about the possibility that the virus could become more widespread.

Today U.K. officials confirmed a fifth area in the country has been hit with the H5N8 strain of the avian flu, since December. The strain has been spread from wild birds to farmed poultry, but has yet to affect humans, according to the U.K. Department of the Environment.

There have been more than 40 countries reporting outbreaks of different strains of the avian flu since last November, according to World Health Organization officials.

With the new avian flu outbreaks popping up in recent months, health experts have been increasingly concerned that one or more of the various strains of avian flu could mutate, increasing the risk of a dangerous new flu that could spread quickly across the globe. Normally the virus spreads among birds, often transmitted long distances by wild birds that migrate. In rare cases people in close contact to the birds become ill and the virus rarely spreads from person to person.

Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center, said the public health community is increasingly concerned that the virus could potentially mutate.

"The concern always is that they could pick up a gene that permits that kind of flu to spread readily from person to person," Schaffner said. Currently "bird flu by itself cannot do that."

However, Schaffner said in recent years the medical community has developed better surveillance technology to find new outbreaks more easily.

"We detect more of the outbreaks and characterize them even more precisely than 10 years ago," he explained.

On Monday, World Health Organization said they were on "high alert" due to the avian flu outbreaks and the possibility of mutation.

During an address to the WHO executive board on Monday, WHO Director Margaret Chan explained one form of the virus first detected in humans in 2015 was created "by gene-swapping among four different viruses." She urged all countries to closely watch for avian flu cases in both birds and humans to stop any new easily transmitted strain of the virus from spreading.

"We cannot afford to miss the early signals," Chan said.

Multiple strains of the avian flu have spread through a diverse range of countries in recent months including Algeria, Finland, China and the United Kingdom, according to the World Organization for Animal Health. While the avian flu rarely affects people, it can have devastating consequences when it does. In China the mortality rate has hovered around 38 percent for the more than 1,000 people infected with a strain of avian flu since 2013, according to Chan.