Scientists find bacteria in Beijing smog that lead to antibiotic resistance
Findings are reason for global concern, warn study’s authors
Scientists have identified bacterial genes that lead to antibiotic resistance, including several that can be resistant to most powerful antibiotics, in air samples from Beijing, which is frequently cloaked in heavy smog,
Researchers from the University of Gothenburg in Sweden analysed 864 DNA samples taken from humans, animals and environments worldwide and found Beijing smog carried the largest number and types of genes identical or highly similar to antibiotic resistance genes (ARG).
Microbial communities from Beijing smog harboured as many as 64.4 different types of ARG.
The researchers also identified in the Beijing smog metagenomes that contained several genes resistant to carbapenems, a class of last-resort antibiotics for treating challenging bacterial infections.
“This may be a more important means of transmission than previously thought,” Joakim Larsson, who led the research, said in a statement. Larsson is a professor at the Sahlgrenska Academy of the University of Gothenburg and director of the institution’s Centre for Antibiotic Resistance Research.
The research did not state whether the bacteria were alive in the air, which would significantly increase the level of threat.
“It is reasonable to believe that there is a mixture of live and dead bacteria, based on experience from other studies of air,” Larsson said.
Although they did not know the proportion of live bacteria in the smog, the presence of many resistance genes “calls for concern given the global threat of carbapenem-resistant Enterobacteriaceae’, the study’s authors warned in the journal Microbiome, where their findings were published.
Researchers said the samples of Beijing smog were collected from a single smog event that lasted for 5 days in January 2013 and samples from more locations would be more preferable.
“We studied only a small number of air samples, so to generalise, we need to examine the air from more places. But the air samples we did analyse showed a wide mix of different resistance genes,” Larsson said.
The World Health Organisation has warned that antibiotic resistance is rising to dangerously high levels in all parts of the world and a growing list of infections – such as pneumonia, tuberculosis, blood poisoning and gonorrhoea – are becoming harder, and sometimes impossible, to treat as antibiotics become less effective.
China, with a long history of antibiotics abuse, is forecast to have 1 million premature deaths each year because of antimicrobial resistance by 2050, according the Global Review on AMR, a report commissioned by former UK Prime Minister David Cameron and published in May.