Everything you need to know about China’s child pneumonia outbreak

China's health-care system is once again in the spotlight as a wave of pneumonia cases sweeps through the country, hitting kids particularly hard. The sudden increase in sick children, and a report suggesting widespread clusters of undiagnosed respiratory illnesses, prompted the World Health Organization to ask for more details in order to allay concerns that a novel pathogen — something like Covid-19 — was the source of the outbreaks. So far, Chinese officials say, it's simply a laundry list of known germs that's causing the problem. 

1. What do health experts say?

Doctors have been warning for weeks that a common bacterial infection would likely cause a spike in "walking pneumonia" cases. In response to the WHO's request for more data, Chinese health authorities said the uptick in outpatient visits and hospitalizations has been due to the spread of mycoplasma pneumoniae, RSV, adenovirus and influenza. Importantly, they say they haven't detected any new pathogens. In turn, the WHO said that while the level of illness is unusually high for this time of year, it's not unusual for winter to bring respiratory diseases. The group advised people to take basic precautions to reduce their risk — wear masks, stay home when sick, wash their hands regularly — and said there's no need for any travel restrictions based on the current situation.

2. What is mycoplasma pneumoniae?

Mycoplasma pneumoniae is a bacteria that typically causes a mild infection, with symptoms that are similar to a common cold. It rarely requires hospitalization but sometimes a cough could for last for weeks and younger children with a nascent immune system are at greater risk of developing pneumonia. That's what's worrying parents. Local media have reported that some of China's top pediatric medical centers have been overwhelmed with sick kids, with some families needing to wait seven hours to see a doctor. Chinese social media has also been awash with photos of crowded waiting rooms and hallways, and children hooked up to intravenous drips.

3. What do I do if I catch it?

Most people will recover from an infection on their own or with over-the-counter medications to help alleviate symptoms. But more severe illness will typically require a course of antibiotics. That's especially concerning since China has the world's highest incidence of mycoplasma pneumoniae that's resistant to a class of antibiotic called macrolides. Up to 60% to 70% of adult cases and up to 80% of cases in kids don't respond to Zithromax and similar drugs, Yin Yudong, an infectious diseases doctor at Beijing Chaoyang Hospital, the nation's top respiratory disease center, told Beijing News earlier this month.

4. Why is it hitting China so hard?

It's unclear why China appears to be the only country facing a major mycoplasma outbreak, while the US and much of Europe have contended with flu and RSV. One study showed mycoplasma pneumoniae was subdued in China for almost two years by Covid countermeasures that have since been lifted. While Chinese health authorities have said the uptick in cases comes earlier than normal, they've also pointed out that other countries have experienced similar surges in respiratory disease after emerging from pandemic restrictions. 

5. Will it spread overseas?

For those outside China, the reports of respiratory-illness outbreaks have brought back memories of the early days of the Covid pandemic, which first emerged as mysterious pneumonia cases in the city of Wuhan in 2019 and whose origin has never been definitely pinned down. But unlike Covid, mycoplasma is a well-known and common germ that tends to cause fresh outbreaks every few years. And other viruses are circulating too, particularly RSV, meaning it's likely that this winter will see countries across the world face a variety of pathogens. 

The reference shelf:

• CDC's explainer on mycoplasma pneumoniae-
• WHO's inquiry into child pneumonia outbreak in China and the country's response
• The germ plaguing China's first post-lockdown winter