(NewsNation) — Reports of a spike in respiratory infections among children in China are triggering frightening flashbacks for some parents in the U.S. who worry the illness could launch another global pandemic like COVID-19.

But China insists it’s just an overlap of common viruses that normally hit kids this time every year, and the World Health Organization (WHO) agrees with that.

China told the WHO the spike was caused by already known viruses like the flu, COVID-19, and RSV and is not the result of a new pathogen.

Mandy Cohen, director of the Centers for Disease Control and Prevention (CDC), testified on Capitol Hill that the agency has no reason to believe an unknown virus is circulating.

Dr. Kristin Englund, an infectious disease specialist at the Cleveland Clinic, joined NewsNation’s “Morning in America” to discuss what is being dubbed “white lung syndrome,” saying there’s little evidence the outbreak is the result of a new pathogen.

“What this seems to be is a very common bacteria that we see year after year called mycoplasma pneumonia,” Englund said. “So this is something that we see surges of every three to four years. And it just seems to be the right time for us to have a surge here.”

Ohio was the first state in the U.S. to report an outbreak of the illness, with an ‘extremely high’ number of children being hospitalized.

The strain of pneumonia spawned 142 pediatric cases in Ohio’s Warren County since August of this year, according to a release from state health officials.

Now, reports indicate doctors in parts of Massachusetts are reporting a spike in child pneumonia cases.

“In western Massachusetts, physicians are seeing ‘a whole lot’ of walking pneumonia, a milder form of the lung condition, which is being caused by a mixture of bacterial and viral infections,” the Daily Mail reports.

Dr. Tom Frieden, former director of the Centers for Disease Control and Prevention, told NewsNation he believes the world is experiencing what is sometimes called an “immunity gap.”

“Although we don’t have all of the information I wish we would have on the details of who’s getting sick and when,” Frieden said. “What we believe is happening is sometimes called an ‘immunity gap,’ that there were years where people weren’t getting infected because of lockdowns and therefore are much more susceptible to influenza, RSV, COVID and other infections.”

According to reports, the term “white lung” comes from pneumonia showing up on X-rays as a whitening of the lung.

“It’s clearly a walking pneumonia,” Dr. Englund said. “I think we’re just simply seeing the effect of the lockdown and coming out of the lockdown in many different places across the world.”

“I think if this was something that was a new pathogen, we wouldn’t see it involving just a specific group like children. We’d be seeing it involving all ages,” Englund continued. “And I think it’s the children that have never seen mycoplasma before that are most at risk.”

Mycoplasma pneumoniae is an ‘atypical’ bacterium that causes lung infection, according to the CDC.

Health officials recommend taking necessary precautions to protect your health, issuing a reminder to “wash your hands, cover your cough, stay home when ill, and stay up to date on vaccines.”

Englund said the lessons Americans learned over the COVID-19 pandemic have “kept us from having cases of influenza and RSV, and mycoplasma pneumonia.”

She shared health tips to teach your children to lower their chances of contracting the illness.

“Just teaching your children the importance of covering their cough, using a Kleenex or coughing into their elbows,” she said. “Making sure that if they’re sick, keep them home so that they’re not getting other children infected.”

“And unfortunately,” she said, “as we start coming into the holidays, if you’re sick, you might have to start skipping those family and friends events.”