40 Years Without A New Antibiotic. Why?

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0:00Most medical science moves at super-speed; researchers are

0:03constantly developing new medications, techniques, surgeries, you name it.

0:08Except for antibiotics: we haven’t gotten a single

0:11new type of antibiotic ready to give to patients in over 40 years.

0:16Hi, I'm Cameron, and this is MinuteEarth.

0:19Almost a hundred years ago, scientists figured out that microbes have evolved

0:23all sorts of chemical weapons to use against other microbes,

0:27AND that we humans can co-opt these weapons for our own use; thus, “antibiotics” were born.

0:34And almost all our antibiotics have been discovered in the exact same way: scientists

0:39take a sample of soil – which tends to contain tons of microbes – and grow those microbes on a

0:44petri dish to see if they produce any chemical weapons that could possibly be useful to us.

0:49Early on, this approach kept turning up new types of antibiotics: some that attack bacteria’s

0:54cell walls, others that attack their protein production, still others that attack their DNA.

0:59But in the 1970s, these discoveries stopped; instead, researchers just kept finding new

1:06variations of the same old types of antibiotics they already knew about.

1:11Now, the problem had to do with the basic discovery process. See,

1:15growing microbes in a lab is a lot like breeding animals in a zoo.

1:19Some animals – and some microbes – multiply and thrive just fine in human-made confines.

1:25But most microbes are like pandas, which are notoriously difficult to keep happy in captivity.

1:31Only about 3% of known microbes actually reproduce in petri dishes.

1:36Plus, like zoo animals, microbes don’t necessarily behave the same way in

1:41captivity as they do in the wild; like, if they aren’t around a lot of competitors,

1:45they might not produce all the chemical weapons they’re capable of making,

1:49so we might be missing out on potentially-useful weapons.

1:53Scientists have tried other antibiotic search strategies – they looked to

1:57human-produced chemicals in search of ones that might kill bacteria,

2:01and even tried to synthesize new antibiotic drugs – but most of them haven’t worked

2:06as well as the chemical weapons that have evolved in nature over millenia.

2:09Because of this discovery drought,

2:11doctors haven’t been able to prescribe a new type of antibiotic in nearly 40 years.

2:16And in the meantime, bacteria have been evolving resistance to the antibiotics we DO have,

2:21leaving some of these weapons –that were once great– powerless.

2:25So scientists are switching up their search strategies.

2:28They’re going back to looking for microbes in the wild, but this time with fancier

2:31tools that don’t require breeding them in petri zoos; for instance,

2:35some new devices allow researchers to grow and observe bacteria in their natural environments.

2:40And these days, researchers don’t even have to grow microbes to see what they’re capable of;

2:45they can simply sift through their DNA to identify potential antibiotic-making genes.

2:50Scientists are also looking for microbes in places other than soil,

2:54like the ocean, which is full of unknown – and potentially useful – microbial life.

3:00And these new methods may be starting to pay off: in 2025,

3:04a group of scientists identified a completely new type of antibiotic,

3:09which just so happens to be shaped like a little molecular lasso.

3:14I hope it means we can round up many more new antibiotics in our future.

3:22This video is brought to by the Science Awareness Project,

3:25which showcases a snapshot of today's scientific medical research from across the

3:29country including the search for new antibiotics using the methods we talk about in this video!

3:34On the website for the Science Awareness Project, you can learn about some of the

3:38medicines and treatments scientists are currently working to discover.

3:41Check it out at www.scienceawarenessproject.org