Social media users falsely claim China pneumonia outbreak 'caused by new Covid variant'

China has been battling a winter outbreak of a bacterial infection known as mycoplasma pneumonia, but some social media users have falsely claimed the surge is caused by a new variant of Covid-19. Medical experts told AFP the evidence does not support this claim, and that the two illnesses have different causes. They have also said mycoplasma pneumonia outbreaks occur every year and the scale of the current surge is not unusual.

"Some doctors have privately revealed that the so-called mycoplasma pneumonia is in fact a variant of Covid-19," says one post in Chinese published on November 7 on X.

A screenshot of the false post on X, taken December 21

The false claim surfaced after the World Health Organization (WHO) identified the latest variant of Covid-19 as JN.1. It has been spreading globally since late October, the world health body said on December 18 (archived link).

Current evidence indicates the new variant is unlikely to put public health systems under strain, but the WHO has warned that respiratory disease may increase during winter due to the virus.

In China, seven cases of JN.1 infection have been detected as of December 10, 2023, according to state media (archived link).

The country has also seen a surge in respiratory illnesses this winter, which has included an outbreak of mycoplasma pneumonia mostly affecting children.

This came around one year after the country loosened its Covid-19 restrictions in December 2022 after three years of pursuing a zero-Covid policy, which was followed by a wave of infections (archived link).

The false claim has been shared elsewhere on X including here, here and here, as well as on other social media platforms such as Gettr and Facebook.

But medical experts have refuted the claim and told AFP there is no evidence the outbreak is due to a new Covid-19 strain.

Bacteria vs virus

Jin Dongyan, a professor from the School of Biomedical Sciences at the University of Hong Kong, told AFP on December 18 that mycoplasma pneumonia is caused by bacteria while Covid-19 is a virus.

"Mycoplasma pneumonia is caused by a bacterium known as mycoplasma pneumoniae. Covid-19 is caused by the SARS-CoV-2 virus," he said in an email (archived links here and here).

He went on to say there was nothing out of the ordinary about China's mycoplasma pneumonia outbreak and that similar surges have been recorded in other countries.

"It is not dramatically different from post-pandemic surges of respiratory infections in other places around the world," he said.

The WHO says Chinese health authorities have provided data indicating the surge in respiratory illness is due to an increase in mycoplasma pneumoniae bacteria, as well as respiratory syncytial virus (RSV), adenovirus, influenza, and pre-existing strains of Covid-19 (archived link).

RSV and adenovirus are common respiratory infections that usually cause mild, cold-like symptoms, according to the US Centers for Disease Control and Prevention (CDC) (archived links here and here).

The WHO has cited information provided by the Chinese government and said no unusual pathogen or symptoms have been recorded in the country.

Paul Hunter, a professor in medicine at the University of East Anglia in England, told AFP that the information does not sound "like an epidemic due to a novel virus".

"If it was, I would expect to see many more infections in adults," he went on to say.

Mycoplasma pneumonia was circulating long before Covid-19 was first detected in late 2019, according to the CDC (archived link).

According to an article in The Lancet, mycoplasma pneumonia infections occur on an annual basis across the globe, with epidemics every few years. The most recent epidemic took place in late 2019 and early 2020 predominantly in Europe and Asia (archived link).

'Lockdown exit'

Jin said the latest outbreak in China could be due to a combination of factors, including a lack of immunity among children, increased testing and the onset of winter.

Francois Balloux, a professor at University College London, said China's harsh restrictions to curb Covid-19 in recent years had resulted in decreased immunity to a range of illnesses.

"Since China experienced a far longer and harsher lockdown than essentially any other country on Earth, it was anticipated that these 'lockdown exit' waves could be substantial in China," he told AFP.

Unless there is new evidence suggesting otherwise, "there is no reason to suspect the emergence of a novel pathogen", Balloux added.

AFP has previously debunked other false information linked to mycoplasma pneumonia in reports here and here.

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