GENEVA, Switzerland - The World Health Organization on Wednesday urged China's population to "follow measures to reduce the risk of respiratory illness" and asked authorities for more information about a reported spike in cases among children in the north of the country.

World Health Organization

"WHO has made an official request to China for detailed information on an increase in respiratory illnesses and reported clusters of pneumonia in children," the UN health body said in a statement posted on social media and confirmed to AFP by a spokesperson.

The WHO said that since mid-October, northern China has reported an increase in "influenza-like illness" compared to the same period in the previous three years.

At a November 13 press conference, Chinese authorities attributed an increase in respiratory illnesses to the lifting of restrictions on COVID-19 and the circulation of known pathogens, including influenza and common bacterial infections known to affect children.

On November 21, media and public disease surveillance system ProMED reported clusters of undiagnosed pneumonia in children in northern China.

The WHO said it was unclear if these reports were related to the infections discussed at the authorities' press conference and that it was seeking clarification.

The WHO "has also requested additional information on recent trends in the circulation of known pathogens, including influenza, SARS-CoV-2 (the virus that gives rise to Covid-19), RSV affecting infants and Mycoplasma pneumoniae, as well as on the degree of overcrowding in the health system," the statement added.

In the meantime, it urged people to take preventative measures, such as vaccination, keeping their distance from the sick, staying at home when ill, regular hand-washing and wearing masks as appropriate.