What 5 infectious disease experts think about China's surge in respiratory illnesses

The infectious disease community is closely watching a surge of mystery illnesses in China that many have compared to the start of the COVID-19 outbreak.

The World Health Organization (WHO) said last week that officials had requested "detailed information" from China about an "increase in respiratory illnesses and reported clusters of pneumonia in children." In a follow-up statement, the WHO reported its officials held a teleconference with Chinese health authorities and were given data that indicated an increase in outpatient visits and hospital admissions of children due to Mycoplasma pneumoniae pneumonia since May, along with RSV, adenovirus and the flu since October.

"Some of these increases are earlier in the season than historically experienced but not unexpected given the lifting of COVID-19 restrictions, as similarly experienced in other countries," the WHO release states. "Chinese authorities advised that there has been no detection of any unusual or novel pathogens or unusual clinical presentations, including in Beijing and Liaoning, but only the aforementioned general increase in respiratory illnesses due to multiple known pathogens."

Still, reports about this situation have been concerning. A headline published by the journal Nature this week reads, "What’s behind China’s mysterious wave of childhood pneumonia?," which is eerily similar to a January 2020 headline for the New York Times at the start of the COVID-19 pandemic that says, "China Grapples With Mystery Pneumonia-Like Illness."

So, what do infectious disease doctors think about all this? We spoke with five physicians to get their takes.

Is this a cause for concern?

Most doctors acknowledge the fact that this is happening in China, where COVID-19 originated, naturally raises eyebrows. "Any health information from China should be verified given what happened with COVID-19 and the fact that we still do not have a clear understanding of the origin of SARS-CoV-2 [the virus that causes COVID-19]," Dr. Richard Watkins, an infectious disease physician and a professor of internal medicine at the Northeast Ohio Medical University, tells Yahoo Life.

"What's going on in China does raise concern," Dr. Ian Michelow, division head of pediatric infectious diseases and immunology at Connecticut Children's Specialty Group, tells Yahoo Life. "Influenza and the original SARS also did arise in China. It's always good to be aware of outbreaks there so we can be prepared."

Dr. William Schaffner, an infectious disease specialist and professor at the Vanderbilt University School of Medicine, agrees. "When the news first broke last week, all of us in infectious diseases wondered whether we had seen this movie before," he tells Yahoo Life. "Fortunately, I think the political leadership of China has learned some lessons from the COVID-19 pandemic."

But China's explanation for what is happening in the country makes sense, according to Dr. Thomas Russo, a professor and chief of infectious diseases at the University at Buffalo in New York. "China says this is due to the usual respiratory viruses such as influenza, RSV, COVID-19 and mycoplasma," he tells Yahoo Life. "While all we know is what China says, I think this is likely to be the case." Schaffner agrees: "Chinese scientists were very convincing that no strange new virus has been found."

Are we seeing similar increases in the U.S.?

To some degree, we already have, Dr. Amesh A. Adalja, a senior scholar at the Johns Hopkins Center for Health Security, tells Yahoo Life. "This is exactly what happened one year ago in the U.S. and other countries when children, who were fully socially interacting, became infected with pathogens that they had avoided during COVID-19 social distancing," he says.

Russo agrees. "Remember that China had a lockdown that extended for three years," he says. "We had a big bump in RSV last year, and China probably has three times that susceptibility pool for RSV. With the lockdown, children haven't seen mycoplasma and influenza as well. It's now catching up with them."

Michelow says it's "not surprising" that China would experience this too, noting that the country is "lagging by a year" due to lockdowns that extended until after last winter. "Because of lockdowns, children weren't exposed to these illnesses when they ordinarily would have built up immunity to these infections," he says. "Nature has made us pay a price for that."

As for mycoplasma, Michelow says that the bacteria tends to cause surges in infections every three to seven years, including in the United States. "We see it every year, and it's usually seasonal — fall and winter," he says. "but some years it happens to be more prevalent than other years."

Although doctors say China's explanation of the situation makes sense, they're also planning to continue to keep an eye on it. "The communication from China has substantially reduced the level of concern," Schaffner says. "That said, the world's public health community and we infectious disease doctors are going to continue to monitor this with great care. We're still a bit uneasy about how freely — or not — China will permit its public health experts to communicate with the Western world."