Antibiotics changed the course of human history, taming diseases that could otherwise wipe people out, like the plague and meningitis. But, 60 years after the start of the golden age of antibiotics, we’re taking them for granted and causing them to stop working. Here’s a bit on how that happened. If you want to know how antibiotics and antibiotic resistance work biologically, check out this link.
Traces of tetracycline, a commonly used antibiotic today, were found in skeletons from 350-550 CE Sudanese Nubia. It’s thought that they were exposed to the bacterium that produces tetracycline through their food or beer, as the traces were found in their bones. The same antibiotic was also found in bodies from late-Roman period Egypt in 1989, and ancient Jordanians seem to have used their red soils full of antibiotic-producing bacteria for medicine. Herbalists in many places used mouldy bread to treat diseases.
The First Modern Antibiotics
The first modern antibiotics weren’t actually called antibiotics — they were called chemotherapeutics.
In 1899, a chemical called pyocyanate, made from the disease-causing bacterium pseudomonas aeruginosa, was used in an attempt to treat a variety of illnesses. It worked for some things but was inconsistent (because the causes of the diseases weren’t really understood) and toxic, so it was shelved.
Then, in the first decade of the 20th century, German physician Paul Ehrlich noticed that certain chemical dyes coloured some bacteria but not others, meaning that certain bacteria could be selectively targeted, which is pretty important in a medicine. (The selectivity principle, by the way, is how the gram test works. It differentiates between gram positive bacteria, which have a thick cell wall made of a protein called peptidoglycan, and gram negative bacteria, which don’t, because a violet stain stays on the peptidoglycan of the gram-positive bacteria and not on the gram-negatives ones. So you just add the chemicals and check if the bacteria are violet or not.) Anyway, Ehrlich then tested a ton of drugs on rabbits infected with syphilis and eventually came up with Salvarsan, a literal lifesaver for sufferers of syphilis, which was extremely common at the time.
About 30 years afterwards, Selman Waksman, who would go on to discover over twenty antibiotics in his life, coined the term “antibiotics”. Pretty handy.
Alexander Fleming and Penicillin
Alexander Fleming is probably the most famous figure in antibiotic history, even though he technically didn’t invent the first antibiotic. He did, however, discover penicillin, which worked against many types of bacteria in low doses and was non-toxic. The story goes that he discovered it in 1928 by accident; after leaving an open Petri dish of bacteria by a window, he came back and discovered that mold had grown and bacteria was absent where mold was present. He spent 12 years trying to get chemists (he was a biologist) to purify and mass-produce the compound from the fungus, then gave up in 1940 just before two chemists called Florey and Chain published a paper on how to do that, and ended up sharing the Nobel Prize with Fleming.
Penicillin – the ‘Wonder Drug’
In 1942, a fire in the Cocoanut Grove nightclub in Boston killed 492 people, making it the worst nightclub fire in history. It changed the world in a lot of ways, spurring world-leading studies into PTSD and grieving and improved safety standards in public buildings, but it also provided a test for penicillin.
Many of the burns victims had to receive skin grafts which are liable to infection with staphylococcus bacteria. These infections could’ve caused further deaths except that 32 litres of penicillin was sent over by Merck to work its miracles. Its success led the US to commission its use for Allied troops fighting in World War 2, another huge lifesaver because it meant that people were much more likely to survive wound infections.
Antibiotics in Agriculture
Another accidental discovery was that antibiotics make animals grow faster. Researchers Rob Stokstad and Thomas Jukes were looking for ways to make chickens grow faster and were trying B12 supplements. They used the remains of streptomyces aureofaciens because that bacteria contained lots of vitamin B12 and soon found that the antibiotic produced by that bacteria made chicks grow 24% more than chicks without the supplement.
Unfortunately, bacteria really want to survive, and antibiotic resistance appeared just a few years after penicillin started being mass-produced. This resulted in penicillin being made prescription only in 1955, quarter-way into the golden age of antibiotics.
So many bacteria became resistant to penicillin — figured out how to stop that antibiotic killing them — that a new drug was needed, and in 1960 that drug, meticillin was produced. It was the golden age of antibiotics, from the 50s to the 70s, when almost all the antibiotics we use now were invented, including ampicillin for meningitis and streptomycin for endocarditis and the plague. People were taking them like candy.
Unfortunately, that had consequences. It only took one year for resistance to meticillin to be found. 1960 invented, 1961 resistance.
In 1976, Stuart Levy showed that antibiotic use in agriculture could cause antibiotic resistance in humans; he fed tetracycline to chickens and found drug-resistant bacteria in their gut one week later. Nevertheless, people kept using antibiotics unnecessarily, including on farms as a growth promoter, ever the “last-resort” drug vancomycin, leading to an epidemic in the 1980s.
MRSA (meticillin-resistant staphylococcus aureus) caused illnesses in otherwise healthy people in the 1990s, and in 2005 20,000 Americans died of MRSA, which was more than the death tolls due to TB and HIV combined.
In the last decade, the harms of antibiotic use in agriculture have received greater attention. The FDA published a plan in 2013 to phase out use of some antibiotics in agriculture, and food giants like McDonalds have promised that they will no longer use meat from antibiotic-fed animals.
This arms race against antibiotic-resistant bacteria (“superbugs”) has not abated, and we still use them incorrectly. The CDC reports that around 50% of prescriptions given to humans are wrongly prescribed — given for viruses instead of bacterial illnesses, for example. And that’s after 70-80% of our antibiotics being used in agriculture.
In 2015, the first new antibiotic in thirty years, teixobactin, was discovered, so progress is being made. Here’s a bunch of ways scientists are working on antibiotic resistance. But we all need to play our parts, so here’s what you can do.
- Lecia Buskak (2016) A Brief History of Antibiotic Resistance: How a Medical Miracle Turned Into the Biggest Public Health Danger of Our Time. Medical Daily. Link.
- The History of Antibiotics. Microbiology Society. Link.
- Rustam Aminov (2010) A Brief History of the Antibiotics Era: Lessons Learned and Challenges for the Future. Frontiers in Microbiology. Link.
- Ling et al (2015) A new antibiotic kills pathogens without detectable resistance. Nature. Link.
- Consumer Reports investigation: talking turkey. (2013). Consumer Reports. Link.