The World Health Organization (WHO) has officially requested more information from Chinese authorities regarding an increase in respiratory illnesses among children in northern China. The request comes in response to undiagnosed pneumonia reported in the region.

The WHO’s interest in the situation is based on unspecified media reports and information gathered through global infectious disease monitoring.

Chinese authorities attribute the increase in respiratory illnesses to the recent lifting of COVID-19 lockdown restrictions. However, the link between these undiagnosed pneumonia clusters and the reported rise in respiratory infections remains unclear, which prompted the WHO to seek more information to understand the extent of the situation better.

Scientists are not quick to identify the recent increase as the beginning of a new global outbreak. They highlight the need for an investigation to determine the cause and nature of the respiratory illnesses in children.

The WHO has also issued a public advisory, urging people in China to take precautionary measures to reduce the transmission of respiratory infections.

The health experts highlight the risks associated with such outbreaks, drawing parallels with past viral threats like SARS and COVID-19. The emergence of new flu strains or viruses often begins with undiagnosed clusters of respiratory illness.

Dr David Heymann, a key player involved in the WHO’s response to the 2002-2003 SARS outbreak, suggests that the background of seasonal respiratory infections may be a likely cause. Heymann pointed out the complexity of identifying outbreaks and determining their cause. He noted that genetic sequencing and isolating cases are crucial in this process.

Researcher Francois Balloux speculates that the current wave of disease in China could be attributed to common respiratory illnesses such as flu, respiratory syncytial virus (RSV), or bacterial infections. Balloux pointed out that China may be experiencing a significant wave of childhood infections, particularly as this is the first winter since lockdown restrictions were lifted, potentially reducing children’s immunity to common bugs.

In response to the WHO’s request for information, China has reported no “unusual or novel pathogens” in clusters of child pneumonia cases. The global health agency sought more data following reports of undiagnosed pneumonia clusters in children in northern China from both media sources and the ProMed global outbreak surveillance system.

The WHO’s public request for information has prompted China’s National Health Commission to announce that they are closely monitoring the diagnosis and care of children with respiratory illnesses.

Since October, northern China has reported an increase in influenza-like illness compared to the same period in the past three years, according to the WHO. The organisation notes that some increases in respiratory illnesses occur earlier in the season than historically experienced but are not unexpected due to the lifting of COVID-19 restrictions, a trend observed in other countries as well.