Antibiotic resistance is on the rise, with a growing number of bacteria no longer responding to the once life-saving drugs.
The World Health Organization calls it “one of the biggest threats to global health”, with no one being immune to the crisis.
Infections are set to become increasingly difficult to treat, leading to longer hospital stays, more expensive care and a rise in deaths.
The effects are already evident, with “superbugs” like MRSA, C.difficile and some gonorrhoea strains no longer responding to their go-to drugs.
What causes antibiotic resistance?
Antibiotics are prescribed to prevent or treat bacterial infections, which include everything from pneumonia and tuberculosis to blood poisoning and Lyme disease.
Over the years, many doctors have mistakenly doled out the drugs to people battling viruses.
“Antibiotics only work against bacteria, through actions such as disrupting their cell wall to kill them or suppressing their division and growth while your own immune system fights them off,” Dr Sarah Brewer, medical director of Healthspan, previously told Yahoo UK.
“Viruses have a very different biology and do not respond to these actions.”
Antibiotics are unlike many other drugs in that the more they are used, the less effective they become.
In 2015, antibiotic use in England alone had increased by 6.5% over the past four years, government data shows.
Random mutations take place within bacteria at a rapid rate. Exposure to an antibiotic “selects” for mutations that protect the bug, including “good ones” in our gut, from destruction.
Bacteria can then pass this genetic advantage to future generations or “horizontally” to other bugs.
And when correctly given out for bacterial infections, many patients fail to take antibiotics as prescribed, coming off the drugs when they start to feel better.
This could mean they stop treatment before the pathogen has been completely eradicated from their body, giving it a better shot of developing resistance.
At least 30% of antibiotics prescribed in the US are “unnecessary”, according to the Centers for Disease Control and Prevention (CDC).
Farmers in the US and parts of Asia also routinely give healthy animals antibiotics to promote growth and prevent disease.
An estimated 80% of antibiotics sold in the US are used in animals, according to scientists from the University of California, San Francisco.
Research suggests antibiotic-resistant bacteria could reach humans via meat.
This is banned in Europe, where farm animals are only given the drugs if struck down with a bacterial infection.
When will antibiotic resistance strike?
Antibiotic resistance is underway and is only set to get worse unless we change how we take the drugs.
More than 2.8 million antibiotic-resistant infections arise every year in the US, killing over 35,000 people, according to the CDC.
One of the most well known is MRSA. This “superbug” is resistant to a widely-used antibiotic, hence its name - methicillin-resistant Staphylococcus auerus.
S. auerus lives harmlessly on the skin of around one in 30 people, according to the NHS.
If it gets into the body, however, it can infect the blood, lungs and urinary tract.
For now, MRSA is usually treatable via antibiotics that still work against it.
However, the infection kills more Americans every year than HIV, AIDS, Parkinson’s, emphysema and murder combined, medical writer C Lee Ventola wrote in the journal Pharmacy & Therapeutics.
Another resistant bacteria is the STI gonorrhoea, which affected more than 44,500 people in England alone in 2017.
In the US, around 150 in every 100,000 caught the infection last year, CDC data shows.
“Gonorrhoea has developed resistance to nearly all of the antibiotics used for its treatment,” according to the CDC.
“We are down to one last recommended and effective class of antibiotics, cephalosporins, to treat this common infection.
“This is an urgent public health threat because gonorrhoea control in the United States largely relies on our ability to successfully treat the infection.”
There may come a time when bacteria stop responding to antibiotics full stop.
However, when this could occur is unclear.
Bacteria are constantly evolving, with some mutations leading to resistance and others not.
The development of new antibiotics has “essentially stalled due to economic and regulatory obstacles”, with 15 of the 18 biggest pharma companies “abandoning the antibiotic field”, Ms Ventola wrote.
Seeing as antibiotics are used for a short time and are “curative”, they are “not as profitable as drugs that treat chronic conditions”, she added.
And once resistance develops and the drug is no longer effective, “profits prematurely curtail”.
Despite this, however, new antibiotics are being discovered.
In February last year, scientists from The Rockefeller University in New York found a new family of the drugs, called malacidins, in soil.
Malacidins “cured” MRSA infections on the skin of rats, with no sign of resistance 20 days later, MailOnline reported.
Penicillin - the most famous antibiotic - was discovered by the Scottish microbiologist Alexander Fleming in 1928, also in soil bacteria.
Other scientists in the UK and US are also developing drugs that kill bacteria via a different method to antibiotics.
How you can help prevent antibiotic resistance
Antibiotics can save lives and should always be taken if prescribed.
However, there are things you can do to help stem the spread of resistance.
If you feel your doctor is too keen to suggest antibiotics, the CDC recommends asking if there is another way you can combat the infection.
In cases where antibiotics are necessary, take the drugs exactly as prescribed, never sharing or skipping doses.
When finished, throw out leftover pills, rather than storing them for future use.
The US Food and Drug Administration recommends mixing leftover drugs with “something undesirable”, like coffee grounds or cat litter.
This makes it less appealing for anyone going through bins, like children or pets, it claims.
Put the mix in a sealed bag and throw it away.
Antibiotics are ineffective against viruses. The CDC stresses you should therefore not pressurise your GP to prescribe them if you have a cold or flu.
Many bacterial infections also have vaccines, such as diphtheria and whooping cough.
Keeping up-to-date on your jabs could prevent the infection in the first place, with antibiotics never being required.