China said no 'unusual or novel pathogens' are behind a spike in respiratory illnesses among children in the north of the country.
It comes after the World Health Organization (WHO) had asked Beijing for more information on the infections after groups including the Program for Monitoring Emerging Diseases (ProMED) reported clusters of undiagnosed pneumonia in children in the country.
The UN agency had sought epidemiologic and clinical information as well as laboratory results through the International Health Regulations mechanism.
WHO China said it was "routine" to request information on increases in respiratory illnesses from member states. Still, it gains increased significance as China and the WHO have faced questions about the transparency of reporting on the earliest COVID-19 cases that emerged in the central Chinese city of Wuhan in late 2019.
The global health body has urged people to take steps to reduce transmission, including getting vaccinated, keeping distance from sick people and wearing masks.
Northern China has recorded an increase in "influenza-like illness" since mid-October when compared to the same period in the previous three years, said the WHO.
What's behind the upsurge in infections?
China's National Health Commission told reporters last week that the respiratory illness spike was due to the lifting of COVID-19 restrictions and the circulation of known pathogens, namely influenza and common bacterial infections that affect children, including mycoplasma pneumonia.
The rise in respiratory illnesses comes as China braces for its first full winter season since it had lifted strict COVID-19 restrictions at the end of last year.
At Beijing's Capital Institute of Pediatrics, 42-year-old Li Meiling told AFP news agency that her eight-year-old daughter was suffering from mycoplasma pneumonia — a pathogen that can cause a sore throat, fatigue and fever.
"It's true that a lot of children her age are ill with this at the moment," she said
But she also thought it was "normal that there are more cases of respiratory illnesses. It's due to the season."
Many other countries saw similar increases in respiratory diseases after easing COVID pandemic measures.
In recent days, media in cities in northern China have posted videos of hospitals crowded with parents and children awaiting checks
"It is just a relatively large seasonal surge, perhaps partly due to chance and partly because there's a bit of 'immunity debt' from the lesser winter surges in the last three years," Ben Cowling, an epidemiologist at Hong Kong University, told Reuters news agency.