Over-the-counter (OTC) lozenges for a sore throat may be fueling the rise of superbugs, research suggests.
A study found antibiotics added to non-prescriptions remedies often fail to wipe out the bacteria causing a patient’s symptoms.
Researchers worry this will strengthen bacteria and enable the species to evolve antibiotic resistance.
Over-the-counter lozenges for a sore throat may be fueling the rise of superbugs (stock)
The research was carried out by Cardiff University and commissioned by Reckitt Benckiser Healthcare.
‘Our work raises doubt about the continued OTC availability of these antibiotics for the treatment of sore throats, especially considering the primarily viral nature of the condition,’ Mr Adrian Shephard, of Reckitt Benckiser, said.
Antibiotics are only effective against bacterial infections, however, many mistakenly believe the drugs will cure viruses. This is concerning because incorrectly treating infections could make life-threatening bacteria harder to kill.
The study comes amid growing fears of antibiotic resistance – partially driven by the unnecessary doling out of the drugs – which has turned once harmless bacteria into superbugs.
The World Health Organization (WHO) has warned if nothing is done we are heading towards a ‘post-antibiotic’ era. In the US alone, around 2million become infected with antibiotic-resistant bacteria every year, resulting in at least 23,000 deaths.
Pneumonia, tuberculosis, gonorrhoea, and salmonellosis are among the growing number of infections that are becoming harder to treat.
To uncover the role antibiotics in OTC medicines play, the researchers analysed four species of bacteria that are known to be developing resistance to commonly-used antibiotics.
Cultures were taken of the species Staphylococcus aureus, Acinetobacter baumannii, Streptococcus pyogenes and Haemophilus influenza.
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.
These were then exposed to decreasing concentrations of gramicidin, neomycin, bacitracin and tyrothricin for 24 hours at human body temperature (37°C/98.6°F).
And the surviving bacteria were then tested for their antibiotic susceptibility.
The researchers were looking for whether the standard concentrations of antibiotics used in OTC drugs are above the minimum inhibitory concentration (MIC) – the lowest amount of a drug required to stop bacterial growth.
Results revealed that for S. aureus and A. baumannii, the concentrations of neomycin, bacitracin and tyrothricin were all above the MIC.
And these concentrations were sufficient to stop bacterial growth.
No MIC could be determined for gramicidin.
The researchers claim this suggests none of the gramicidin concentrations tested were able to prevent the growth of S. aureus or A. baumannii.
‘We were concerned to find that some of the OTC antibiotics used in sore throat preparations were not sufficiently concentrated to prevent growth of common human pathogens and are enabling these pathogens to develop resistance,’ Mr Shephard said.
H. influenza was unable to grow in any of the antibiotics or concentrations tested.
And S. pyogenes only demonstrated growth in very weak concentrations – one per cent and 5 per cent of those found in medicines – when exposed to neomycin.
When S. aureus was exposed to bacitracin, it eventually showed growth after 144 hours at high concentrations.
And a culture grown in a lower concentration of the drug was found to have decreased susceptibility to the antibiotics gentamicin, fusidic acid and ciprofloxacin.
This suggests the bacteria may have benefited from cross resistance.
This occurs when a bug develops resistance to an antibiotic not as a result of direct exposure to the drug but by exposure to a related substance.
This research was presented at this year’s European Congress of Clinical Microbiology & Infectious Diseases in Amsterdam, Netherlands.
Co-author Jean-Yves Maillard – professor of pharmaceutical microbiology at the school of pharmacy and pharmaceutical sciences – added: ‘This was an interesting study that showed once again the potential of bacteria to adapt to chemotherapeutic antibiotics.
‘[It highlights] the need for a prudent and perhaps controlled use of antibiotics in practice.’
WORLD’S WORST CASE OF GONORRHOEA WAS CURED WITH A LAST-DITCH ANTIBIOTIC
An Englishman who caught the ‘world’s worst’ case of super-gonorrhoea was cured in April 2018 with a last-ditch antibiotic.
In the first recorded case worldwide, the unidentified man caught a version of the sexually transmitted infection (STI) that was resistant to two crucial drugs.
Health officials revealed he caught it from a one-night stand with a woman during his travels to south east Asia earlier this year – despite having a girlfriend in the UK.
Public Health England (PHE) issued a warning over the the STI, which is resistant to ceftriaxone and azithromycin – the two drugs recommended for gonorrhoea.
In a statement, the Government agency revealed the man – whose location has also been withheld – was cured with the antibiotics ertapenem.
Dr Gwenda Hughes, head of STIs at PHE, said: ‘We are pleased to report the case of multi-drug resistant gonorrhoea has been successfully treated.
‘Investigations have also revealed there has been no further spread of this infection within the UK.’
Dr Hughes did warn that ‘we expect to see further cases of multi-drug resistant gonorrhoea in the future’.
World Health Organization (WHO) experts raised fears two years ago the STI, once known as the ‘clap’, could become immune to antibiotics in a ‘matter of years’.
The WHO recommends patients are given ceftriaxone and azithromycin to combat gonorrhoea, the third most common STI in Britain.
Officials said: ‘This is the first global report of high-level azithromycin resistant N. gonorrhoeae which is also resistant to ceftriaxone.’