Map: These states have the highest levels of flu activity

CDC reports super flu infections are on the rise

The CDC reported that the United States is seeing a massive increase in flu cases this winter, many of them attributed to the so-called "super flu." LiveNOW's J Russell brings UCSF Dr. Peter Chin-Hong into the conversation to discuss.

The severe flu season sweeping the U.S. is likely to get worse in coming weeks, health officials say, with new data already surpassing the harsh flu epidemic of last winter.

Forty-five states were reporting high or very high flu activity during the week of Christmas, up from 30 states the week before, according to the Centers for Disease Control and Prevention. Infectious disease experts say flu season hasn’t peaked yet, as more people are being hospitalized with a particularly bad strain that’s making people sicker. Here’s the latest:

Severe strain dominates

Big picture view:

The higher numbers appear to be driven by the type of flu that’s been spreading, public health experts say.

One type of flu virus, called A H3N2, historically has caused the most hospitalizations and deaths in older people. So far this season, that’s the type most frequently reported. More than 90% of the H3N2 infections analyzed were a new version — known as the subclade K variant — that differs from the strain in this year’s flu shots. But doctors say the flu vaccine will still help protect against severe illness and death. 

About 130 million flu shots have been administered so far this flu season (Photo by FREDERIC J. BROWN/AFP via Getty Images)

By the numbers:

The CDC estimates at least 11 million illnesses from the flu so far this year, with 120,000 hospitalizations and 5,000 deaths. 

Flu vaccine changes

Dig deeper:

The data was released the same day the Trump administration said it will no longer recommend flu shots for all children, though as of Wednesday, the CDC website still said everyone 6 months and older should get a flu shot if you haven’t already done so. According to the CDC, about 130 million flu vaccines have been administered so far this season. 

RELATED: US drops number of vaccines it recommends for every child: What to know

Which states have the most flu cases?

Local perspective:

Here’s where flu activity is the highest.

Flu symptoms

According to the CDC, flu symptoms include:

• fever or feeling feverish/chills (not everyone will have a fever)
• cough
• sore throat
• runny or stuffy nose
• muscle or body aches
• headaches
• fatigue
• vomiting and diarrhea (more common in children than adults)

What to do if you get the flu

What you can do:

The CDC recommends taking antiviral drugs to treat the flu as soon as possible when you feel sick. The drugs, which are only available with a prescription, can alleviate symptoms and shorten the amount of time you’re sick. They’re different from antibiotics, which do not treat the flu. The four FDA-approved flu drugs are: 

• oseltamivir phosphate (available as a generic version or under the trade name Tamiflu)
• zanamivir (trade name Relenza)
• peramivir (trade name Rapivab)
• baloxavir marboxil (trade name Xofluza)

The CDC says you should also take steps to protect those around you from getting sick, and stay home until your symptoms are gone and you’re fever-free for at least 24 hours, without taking a fever-reducing medication.