[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:06.79,0:00:11.04,Default,,0000,0000,0000,,What if I told you there were trillions\Nof tiny bacteria all around you?
Dialogue: 0,0:00:11.04,0:00:12.52,Default,,0000,0000,0000,,It's true.
Dialogue: 0,0:00:12.52,0:00:16.62,Default,,0000,0000,0000,,Microorganisms called bacteria\Nwere some of the first life forms
Dialogue: 0,0:00:16.62,0:00:18.26,Default,,0000,0000,0000,,to appear on Earth.
Dialogue: 0,0:00:18.26,0:00:20.86,Default,,0000,0000,0000,,Though they consist\Nof only a single cell,
Dialogue: 0,0:00:20.86,0:00:25.81,Default,,0000,0000,0000,,their total biomass is greater than\Nthat of all plants and animals combined.
Dialogue: 0,0:00:25.81,0:00:29.07,Default,,0000,0000,0000,,And they live virtually everywhere:
Dialogue: 0,0:00:29.07,0:00:33.56,Default,,0000,0000,0000,,on the ground, in the water,\Non your kitchen table, on your skin,
Dialogue: 0,0:00:33.56,0:00:35.94,Default,,0000,0000,0000,,even inside you.
Dialogue: 0,0:00:35.94,0:00:38.28,Default,,0000,0000,0000,,Don't reach for the \Npanic button just yet.
Dialogue: 0,0:00:38.28,0:00:42.10,Default,,0000,0000,0000,,Although you have 10 times more\Nbacterial cells inside you
Dialogue: 0,0:00:42.10,0:00:46.29,Default,,0000,0000,0000,,than your body has human cells,\Nmany of these bacteria are harmless
Dialogue: 0,0:00:46.29,0:00:50.74,Default,,0000,0000,0000,,or even beneficial,\Nhelping digestion and immunity.
Dialogue: 0,0:00:50.74,0:00:54.90,Default,,0000,0000,0000,,But there are a few bad apples\Nthat can cause harmful infections,
Dialogue: 0,0:00:54.90,0:00:58.09,Default,,0000,0000,0000,,from minor inconveniences to\Ndeadly epidemics.
Dialogue: 0,0:00:58.09,0:01:04.22,Default,,0000,0000,0000,,Fortunately, there are amazing medicines\Ndesigned to fight bacterial infections.
Dialogue: 0,0:01:04.22,0:01:08.13,Default,,0000,0000,0000,,Synthesized from chemicals or\Noccurring naturally in things like mold,
Dialogue: 0,0:01:08.13,0:01:13.98,Default,,0000,0000,0000,,these antibiotics kill or neutralize bacteria\Nby interrupting cell wall synthesis
Dialogue: 0,0:01:13.98,0:01:18.28,Default,,0000,0000,0000,,or interfering with vital processes\Nlike protein synthesis,
Dialogue: 0,0:01:18.28,0:01:21.06,Default,,0000,0000,0000,,all while leaving human cells unharmed.
Dialogue: 0,0:01:21.06,0:01:24.45,Default,,0000,0000,0000,,The deployment of antibiotics \Nover the course of the 20th century
Dialogue: 0,0:01:24.45,0:01:27.97,Default,,0000,0000,0000,,has rendered many previously dangerous\Ndiseases easily treatable.
Dialogue: 0,0:01:27.97,0:01:30.87,Default,,0000,0000,0000,,But today, more and more\Nof our antibiotics
Dialogue: 0,0:01:30.87,0:01:32.99,Default,,0000,0000,0000,,are becoming less effective.
Dialogue: 0,0:01:32.99,0:01:35.59,Default,,0000,0000,0000,,Did something go wrong\Nto make them stop working?
Dialogue: 0,0:01:35.59,0:01:40.45,Default,,0000,0000,0000,,The problem is not with the antibiotics\Nbut the bacteria they were made to fight,
Dialogue: 0,0:01:40.45,0:01:44.59,Default,,0000,0000,0000,,and the reason lies in Darwin's theory\Nof natural selection.
Dialogue: 0,0:01:44.59,0:01:49.62,Default,,0000,0000,0000,,Just like any other organisms,\Nindividual bacteria can undergo random mutations.
Dialogue: 0,0:01:49.62,0:01:53.24,Default,,0000,0000,0000,,Many of these mutations\Nare harmful or useless,
Dialogue: 0,0:01:53.24,0:01:56.48,Default,,0000,0000,0000,,but every now and then,\None comes along that gives its organism
Dialogue: 0,0:01:56.48,0:01:59.06,Default,,0000,0000,0000,,an edge in survival.
Dialogue: 0,0:01:59.06,0:02:01.74,Default,,0000,0000,0000,,And for a bacterium,\Na mutation making it resistant
Dialogue: 0,0:02:01.74,0:02:05.21,Default,,0000,0000,0000,,to a certain antibiotic\Ngives quite the edge.
Dialogue: 0,0:02:05.21,0:02:08.00,Default,,0000,0000,0000,,As the non-resistant bacteria\Nare killed off,
Dialogue: 0,0:02:08.00,0:02:11.37,Default,,0000,0000,0000,,which happens especially quickly\Nin antibiotic-rich environments,
Dialogue: 0,0:02:11.37,0:02:13.90,Default,,0000,0000,0000,,like hospitals,\Nthere is more room and resources
Dialogue: 0,0:02:13.90,0:02:17.88,Default,,0000,0000,0000,,for the resistant ones to thrive,\Npassing along only the mutated genes
Dialogue: 0,0:02:17.88,0:02:19.72,Default,,0000,0000,0000,,that help them do so.
Dialogue: 0,0:02:19.72,0:02:22.35,Default,,0000,0000,0000,,Reproduction isn't the\Nonly way to do this;
Dialogue: 0,0:02:22.35,0:02:26.60,Default,,0000,0000,0000,,some can release their DNA upon death\Nto be picked up by other bacteria,
Dialogue: 0,0:02:26.60,0:02:29.18,Default,,0000,0000,0000,,while others use a method\Ncalled conjugation,
Dialogue: 0,0:02:29.18,0:02:32.46,Default,,0000,0000,0000,,connecting through pili \Nto share their genes.
Dialogue: 0,0:02:32.46,0:02:38.29,Default,,0000,0000,0000,,Over time, the resistant genes proliferate,\Ncreating entire strains of resistant super bacteria.
Dialogue: 0,0:02:38.29,0:02:43.11,Default,,0000,0000,0000,,So, how much time do we have\Nbefore these superbugs take over?
Dialogue: 0,0:02:43.11,0:02:46.74,Default,,0000,0000,0000,,Well, in some bacteria,\Nit's already happened.
Dialogue: 0,0:02:46.74,0:02:50.38,Default,,0000,0000,0000,,For instance, some strands \Nof staphylococcus aureus,
Dialogue: 0,0:02:50.38,0:02:54.18,Default,,0000,0000,0000,,which causes everything from\Nskin infections to pneumonia and sepsis,
Dialogue: 0,0:02:54.18,0:02:57.46,Default,,0000,0000,0000,,have developed into MRSA,\Nbecoming resistant to
Dialogue: 0,0:02:57.46,0:03:02.33,Default,,0000,0000,0000,,beta-lactam antibiotics,\Nlike penicillin, methicillin, and oxacillin.
Dialogue: 0,0:03:02.33,0:03:04.60,Default,,0000,0000,0000,,Thanks to a gene\Nthat replaces the protein
Dialogue: 0,0:03:04.60,0:03:07.40,Default,,0000,0000,0000,,beta-lactams normally target\Nand bind to,
Dialogue: 0,0:03:07.40,0:03:10.86,Default,,0000,0000,0000,,MRSA can keep making \Nits cell walls unimpeded.
Dialogue: 0,0:03:10.86,0:03:13.91,Default,,0000,0000,0000,,Other super bacteria,\Nlike salmonella,
Dialogue: 0,0:03:13.91,0:03:17.08,Default,,0000,0000,0000,,even sometimes produce enzymes\Nlike beta-lactams
Dialogue: 0,0:03:17.08,0:03:20.70,Default,,0000,0000,0000,,that break down antibiotic attackers\Nbefore they can do any damage,
Dialogue: 0,0:03:20.70,0:03:25.05,Default,,0000,0000,0000,,and E. coli, a diverse group of bacteria\Nthat contains strains that cause
Dialogue: 0,0:03:25.05,0:03:28.18,Default,,0000,0000,0000,,diarrhea and kidney failure,\Ncan prevent the function
Dialogue: 0,0:03:28.18,0:03:31.03,Default,,0000,0000,0000,,of antibiotics, like quinolones,\Nby actively booting
Dialogue: 0,0:03:31.03,0:03:34.57,Default,,0000,0000,0000,,any invaders that manage\Nto enter the cell.
Dialogue: 0,0:03:34.57,0:03:36.39,Default,,0000,0000,0000,,But there is good news.
Dialogue: 0,0:03:36.39,0:03:39.61,Default,,0000,0000,0000,,Scientists are working to stay\None step ahead of the bacteria,
Dialogue: 0,0:03:39.61,0:03:43.09,Default,,0000,0000,0000,,and although development of\Nnew antibiotics has slowed in recent years,
Dialogue: 0,0:03:43.09,0:03:47.99,Default,,0000,0000,0000,,the World Health Organization has made it\Na priority to develop novel treatments.
Dialogue: 0,0:03:47.99,0:03:51.27,Default,,0000,0000,0000,,Other scientists are investigating\Nalternate solutions,
Dialogue: 0,0:03:51.27,0:03:55.78,Default,,0000,0000,0000,,such as phage therapy\Nor using vaccines to prevent infections.
Dialogue: 0,0:03:55.78,0:03:59.62,Default,,0000,0000,0000,,Most importantly, curbing the excessive\Nand unnecessary use of antibiotics,
Dialogue: 0,0:03:59.62,0:04:02.68,Default,,0000,0000,0000,,such as for minor infections\Nthat can resolve on their own,
Dialogue: 0,0:04:02.68,0:04:06.34,Default,,0000,0000,0000,,as well as changing medical practice\Nto prevent hospital infections,
Dialogue: 0,0:04:06.34,0:04:10.36,Default,,0000,0000,0000,,can have a major impact\Nby keeping more non-resistant bacteria alive
Dialogue: 0,0:04:10.36,0:04:13.08,Default,,0000,0000,0000,,as competition for resistant strains.
Dialogue: 0,0:04:13.08,0:04:16.84,Default,,0000,0000,0000,,In the war against super bacteria,\Ndeescalation may sometimes work better
Dialogue: 0,0:04:16.84,0:04:19.62,Default,,0000,0000,0000,,than an evolutionary arms race.