According to new reports, bird flu is back. Here's what you need to know.

Korin Miller
South Korean soldiers national veterinary and quarantine service members into the duck farm affected by a highly pathogenic avian influenza in Cheonan, southeast of Seoul, in December 2003. (Photo: Getty Images)

Bird flu makes headlines here and there, but it has largely been out of the news in the past few years. Now, it seems, it’s back.

Global health officials are warning that there is a concerning bird flu circulating throughout Asia. Known as the H7N9 virus, this form of bird flu is in its “fifth wave,” per the Centers for Disease Control and Prevention. According to the New York Times, nearly 1,600 people have tested positive for the infection and almost 40 percent of them have died.

Most of these people have been in close contact with live poultry, but small clusters of the disease imply that it might now be passed from person to person. The H7N9 virus has become lethal to birds, which makes it more harmful to people but potentially easier to detect. The virus has also split into two different strains, the Yangtze and the Pearl, making it difficult for experts to create a vaccine.

“The number of cases is accelerating, and there are some changes in the virus that are worrisome,” Amesh A. Adalja, MD, a board-certified infectious disease physician and affiliated scholar at the Johns Hopkins Center for Health Security, tells Yahoo Lifestyle. Before you panic, know this: The virus is not currently circulating in the U.S. Still, it’s a good idea to keep an eye on it. Here are some important things you need to know about the bird flu.

What is bird flu, exactly?

Also known as avian flu, it’s a form of the flu virus that naturally circles through birds. “Sometimes it can jump the species barrier into humans and spark a pandemic, because it’s not a type of flu that human immune systems have been exposed to,” Adalja says. Pigs can be infected with human and bird flus and sometimes can serve as a “mixing vessel” that allows the virus to shuffle genes around, he says.

How does someone contract it?

People typically get bird flu from coming into close contact with poultry or pigs, either by working with the animals or butchering them. Most of the time it’s what’s called a dead-end infection — a person gets sick and doesn’t pass the flu on to others, Adalja says. But in some cases, the virus is transmitted to other people, and that’s when there’s a risk of a pandemic forming.

What are the major symptoms of bird flu?

Bird flu causes a serious respiratory illness in people. “It will start out with a cough, congestion, fever, muscle aches and pains,” Adalja says. Often bird flu causes people to have very severe respiratory distress and can cause pneumonia, which can be fatal. “These aren’t benign illnesses when they happen in humans” Adalja says. “That’s what’s scary about them.”

Will getting a flu shot protect me?

Unfortunately, no. “Avian flu viruses are usually different enough from seasonal flu viruses that the shot won’t help,” Adalja says.

How is it treated?

Bird flu is treated like the “regular” flu. That means patients are often given antiviral medication like Tamiflu, Adalja says. If they have severe respiratory issues, they may need supplemental oxygen and even ICU care.

Again, the latest strain of bird flu is currently restricted to people who closely interact with poultry, and it has not appeared in the U.S. However, if you recently traveled to China or another area that’s been struggling with the H7N9 virus and you start to develop symptoms, call your doctor immediately.

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