As well as soot and exhaust fumes city air could be filling our lungs with antibiotic resistant genes, a study has found.
Some two million people in the US are thought to become infected with drug-resistant bacteria every year, and they could be inhaling them from the air.
The genes which cause bacteria to become immune to medication – antibiotic resistant genes (ARGs) – are able to move between different bacteria and also from bacteria into the environment, experts say.
And research by the American Chemical Society revealed scientists have found the airborne genes in farms and parks in America.
This confirms drug resistance could be spread through the air, adding another element to a growing challenge for scientists around the world.
It suggests bacteria could acquire their ability to survive antibiotic treatment – and become superbugs – from the air we breathe.
The researchers added the ways pollution is measured and the public are warned should be changed to explain the risk of breathing in the resistant genes.
Scientists say air quality monitoring must also focus on the risk of breathing in antibiotic resistant genes, as well as lung-damaging soot and fumes
Antibiotic resistance is a spreading global problem which means once easily-treatable infections could become superbugs that cannot be cured.
Figures estimate these superbugs – which develop from people overusing or wrongly using antibiotics – will kill 10 million people a year by 2050.
Experts predict a ‘post-antibiotic’ world
The World Health Organisation has warned the world could enter a ‘post-antibiotic’ era in which medicines no longer work as bacteria become tougher and tougher.
The new research, led by Peking University, examined the levels of antibiotic resistant genes in the air of 19 cities around the world.
San Francisco had the highest levels of the airborne ARGs, whereas the air in Beijing contained genes with resistance to a wider range of antibiotics.
These genes are a risk to health because they may be absorbed by bacteria which were not previously able to survive antibiotics, meaning more and more infections could become difficult or impossible to treat.
Cities worldwide have penicillin resistant genes in the air
In all cities, genes were most commonly resistant to penicillin and similar drugs, as well as a class of medicines called quinolones which are used to treat urinary tract infections, gonnorhoea, and pneumonia.
Other cities the researchers tested included Paris, Johannesburg, Zurich, Warsaw, Hong Kong, Brisbane and Melbourne.
The air of six of the cities contained genes resistant to a last-resort treatment for highly infectious hospital superbug. MRSA, which is already immune to most antibiotics.
Work reveals the ‘threat of airborne transmission’
In the study the researchers said: ‘Remote regions even without using antibiotics could be exposed to the second hand ARGs, which are initially being developed in other regions but transported elsewhere.
‘This work highlights the threat of airborne transmission of ARGs and the need of redefining our current air quality standards in terms with public health in an urban city.’
WHAT IS ANTIBIOTIC RESISTANCE?
Antibiotics have been doled out unnecessarily by GPs and hospital staff for decades, fueling once harmless bacteria to become superbugs.
The World Health Organization (WHO) has previously warned if nothing is done the world is heading for a ‘post-antibiotic’ era.
It claimed common infections, such as chlamydia, will become killers without immediate solutions to the growing crisis.
Bacteria can become drug resistant when people take incorrect doses of antibiotics or if they are given out unnecessarily.
Chief medical officer Dame Sally Davies claimed in 2016 that the threat of antibiotic resistance is as severe as terrorism.
Figures estimate that superbugs will kill 10 million people each year by 2050, with patients succumbing to once harmless bugs.
Around 700,000 people already die yearly due to drug-resistant infections including tuberculosis (TB), HIV and malaria across the world.
Concerns have repeatedly been raised that medicine will be taken back to the ‘dark ages’ if antibiotics are rendered ineffective in the coming years.
In addition to existing drugs becoming less effective, there have only been one or two new antibiotics developed in the last 30 years.
In September, the WHO warned antibiotics are ‘running out’ as a report found a ‘serious lack’ of new drugs in the development pipeline.
Without antibiotics, C-sections, cancer treatments and hip replacements will become incredibly ‘risky’, it was said at the time.