By Jessica McDonald

Five Republican senators have penned a letter to President Joe Biden urging him to ban travel to the U.S. from China because of a surge in “mystery” respiratory illnesses among children. But the letter selectively cites outdated information from the World Health Organization, and experts say the illnesses are likely due to known viruses and bacteria and aren’t unexpected.

Since at least mid-October, there has been an uptick in respiratory illnesses in children in northern China. Initially there was some concern about the situation, based on descriptions in local media on Nov. 21 of possible clusters of undiagnosed pneumonia in kids. But further investigation suggests that the illnesses are a result of known pathogens, including Mycoplasma pneumoniae, a pneumonia-causing bacteria, as well as respiratory syncytial virus, or RSV, adenovirus and influenza virus.

“Some of these increases are earlier in the season than historically experienced, but not unexpected given the lifting of COVID-19 restrictions [in China], as similarly experienced in other countries,” a Nov. 23 update from the WHO reads, specifically advising against travel restrictions, as the WHO typically does.

Last year, American kids were hit hard by an earlier-than-usual surge of RSV, likely due to an “immunity gap” phenomenon. Public health precautions during the COVID-19 pandemic reduced exposure to a variety of pathogens, leaving more people without immunity and susceptible to these diseases, allowing for a burst of cases in the population at the same time. China only lifted its “zero-COVID” policy, which was far more extreme than anything implemented in the U.S., in late 2022.

Despite evidence indicating that the surge in pediatric illnesses is largely expected and not suggestive of a new pathogen, several Republicans have pushed the notion that the illnesses in China are a threat to the U.S. — and have called for a ban on travel from that country.

In a Dec. 1 letter, Sens. Marco Rubio and Rick Scott of Florida, J.D. Vance of Ohio, Tommy Tuberville of Alabama, and Mike Braun of Indiana claimed that “the world faces another unknown pathogen emanating from the PRC that could spread to other countries, including the United States” — and that the prudent response is to halt travel from China.

“A ban on travel now could save our country from death, lockdowns, mandates, and further outbreaks later,” they wrote.

The quintet misleadingly referred to “the dangers posed by this new illness” — even though the evidence at this time does not point to a novel pathogen. 

On X, the platform formerly known as Twitter, Rubio and Scott repeated this incorrect impression. 

“A new mysterious respiratory illness is emerging in China and the mistakes from COVID-19 cannot be repeated,” Rubio said in a Dec. 1 tweet, adding that he had sent a letter to Biden “urging him to impose a travel ban on China until we gain further knowledge on this virus.” 

In a subsequent tweet, Rubio again referred to a “‘mystery pneumonia’ outbreak.” The next day, Scott similarly wrote on X that “the U.S. must do everything possible to prevent this new illness from reaching American shores.”

Not Very ‘Mysterious’

As we said, a review of the available evidence does not suggest that the pediatric illnesses in China are due to a new illness. Instead, the WHO and other independent experts say it makes sense that what’s happening in China is a resurgence of multiple known respiratory pathogens as a result of normal seasonal increases combined with the lifting of pandemic restrictions.

In a Nov. 24 interview with STAT, Maria Van Kerkhove, director of the WHO’s epidemic and pandemic preparedness and prevention unit, said that the evidence provided by China, some of which the WHO could cross-check, is consistent with an “immunity gap” explanation.

“This is not an indication of a novel pathogen,” she said. “This is expected. This is what most countries dealt with a year or two ago.”

Chinese health officials said that none of the patients had unusual presentations or were unable to be diagnosed, Van Kerkhove said, adding that the data suggest the uptick in disease “is an overall increased wave, not discrete clusters.”

Parents with children suffering from respiratory diseases at a children’s hospital in Chongqing, China, on Nov. 23. Photo by Costfoto/NurPhoto via Getty Images.

On Nov. 30, testifying before a House subcommittee, the newly installed Centers for Disease Control and Prevention director, Dr. Mandy Cohen, said the agency did not think the illnesses were due to a novel pathogen.

Dr. Scott Gottlieb, a Food and Drug Administration commissioner under former President Donald Trump, similarly told CBS News on Dec. 3 that “it does appear to be more usual strains of illness. So, there’s no reason to believe that there’s something novel spreading there.”

The CDC told us in an email that the agency is in contact with its own staff in China, as well as local health authorities and global health partners, and current information supports the conclusion that the respiratory illnesses are “NOT due to a new or novel virus or illness.”

In China this year, the CDC said, mycoplasma bacterial infections were on the rise at least as early as September, but in November flu replaced mycoplasma as the primary cause of pediatric respiratory illnesses. 

Mycoplasma infections are known to be cyclical, spiking in frequency every three to seven years. China has seen upticks in 2011, 2015 and 2019, the agency said, so a surge in 2023 is not surprising.

Mycoplasma infections tend to be longer-lasting but less severe than other forms of pneumonia. Cases are most common in school-aged children and young adults and can usually be easily treated with antibiotics, although antibiotic resistance can be a problem in some parts of the world, including China.

“I don’t think it’s accurate to describe the rise in pediatric illnesses in China as mysterious,” Jennifer Nuzzo, an epidemiologist and director of the Pandemic Center at Brown University School of Public Health, told us in an email.

When news first broke of the situation in China, the word “mysterious” was used in some reporting. On Nov. 21, ProMed, an emerging disease alert system, flagged a local news story describing children’s hospitals in Beijing and Liaoning, a province bordering North Korea, being overrun with pneumonia cases. The ProMed alert said the news report “suggests a widespread outbreak of an undiagnosed respiratory illness” in children.

This garnered international attention, including from the WHO, which issued a statement on Nov. 22 asking for more information from China. Chinese officials met with the WHO the next day, which is also when the WHO released its updated assessment

But even before WHO’s update, experts noted that it wouldn’t make sense that a novel pathogen would only affect children — and that the most likely explanation is a resurgence of known illnesses after children in China avoided those germs for about three years.

The Republican letter, notably, selectively draws on statements the WHO made in its earlier Nov. 22 statement, writing that the organization “says it is unclear if the disease is due to an overall increase in respiratory infections or separate events” and that it has “requested that the CCP share ‘detailed information’ about the mystery illness.” 

This omits the fact that by Nov. 23 — a full week before the letter was issued — China did provide more information, and that WHO officials and others see no evidence of a new pathogen being involved.

No Connection to Ohio Pediatric Pneumonia Outbreak

Separately, some people online have been erroneously linking an outbreak of pediatric pneumonia in Ohio to the situation in China. 

“The ‘Mystery pneumonia’ affecting kids and ripping through China and parts of Europe, is reportedly now in America,” conservative commentator Charlie Kirk posted on X on Nov. 30. “142 child cases of ‘white lung syndrome’ have now been recorded in Warren County, Ohio since August, meaning if true, it’s been here for months.”

“Mystery outbreak of pneumonia has hit several parts of China, and now Ohio is the first American location to report an outbreak of the illness,” reads another misleading post on Instagram.

The circumstances in Ohio and China are similar, but there’s nothing to suggest that they’re related.

Health officials in Warren County, located in the southwestern part of the state, explained on Nov. 29 that while they’ve seen “an extremely high number of pediatric pneumonia cases” this fall, they “do not think this is a novel/new respiratory disease but rather a large uptick in the number of pneumonia cases normally seen at one time.”

“There has been zero evidence of this outbreak being connected to other outbreaks, either statewide, nationally or internationally,” officials added in another statement on Nov. 30.

“We don’t have any evidence to suggest this is anything but routine standard winter bugs causing pneumonia in higher rates in kids,” Dr. Clint Koenig, the medical director at the Warren County Health Department, told the Washington Post. 

The number of pneumonia cases in the county has been unusually high — 145 since August, as of the end of November, meeting the Ohio Department of Health’s definition of an outbreak. But the cases have not been more severe than usual, and no children have died. Moreover, contrary to suggestions on social media, the cases are not due to a single mysterious illness. Multiple different known pathogens, including adenovirus and mycoplasma and pneumococcus bacteria, have been recovered, officials said.

As of Dec. 1, according to CDC data, rates of pneumonia in children across the entire U.S. are not abnormally high for the season. 

Many news reports and social media posts have used the “white lung” moniker to describe the pneumonia cases, but this is not a medical term and could incorrectly suggest increased severity or a novel disease.

Pneumonia can show up on a chest X-ray as white patches, reflecting the infection’s inflammation or fluid buildup. Normally, since lungs are filled with air, they don’t block much radiation and will appear dark. But a fully white lung X-ray is rare — sometimes called lung “white out” in the medical literature — and would indicate the lung has collapsed or has another serious problem.

“This white lung syndrome is not a thing as it relates to any of our cases,” Koenig told the Washington Post. “There’s no data to support the current colloquial use of that phrase with what we are seeing. It’s inappropriate. It’s inaccurate.”


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