Antibiotics: behind the scenes, they enable much of modern medicine. We use them to cure infectious diseases, but also to safely facilitate everything from surgery to chemotherapy to organ transplants. Without antibiotics, even routine medical procedures can lead to life-threatening infections. And we’re at risk of losing them.
Antibióticos: entre bastidores, permiten gran parte da medicina moderna. Usámolos para curar enfermidades infecciosas, pero tamén para aumentar a seguridade en procedementos como cirurxías, a quimioterapia e o transplante de órganos. Sen antibióticos, incluso procedementos médicos de rutina poden levar a infeccións letais, e corremos o risco de perdelos.
Antibiotics are chemicals that prevent the growth of bacteria. Unfortunately, some bacteria have become resistant to all currently available antibiotics. At the same time, we’ve stopped discovering new ones. Still, there’s hope that we can get ahead of the problem.
Os antibióticos son substancias químicas que evitan o crecemento das bacterias. Por desgraza, algunhas bacterias volvéronse resistentes a todos os antibióticos dispoñibles. Ao mesmo tempo, paramos de descubrir outros novos. A pesar de todo, hai esperanza de que poidamos resolver o problema.
But first, how did we get into this situation? The first widely used antibiotic was penicillin, discovered in 1928 by Alexander Fleming. In his 1945 Nobel Prize acceptance speech, Fleming warned that bacterial resistance had the potential to ruin the miracle of antibiotics. He was right: in the 1940s and 50s, resistant bacteria already began to appear.
Pero, primeiro, como acabamos nesta situación? O primeiro antibiótico amplamente utilizado foi a penicilina, descuberta en 1928 por Alexander Fleming. No seu discurso de aceptación do Premio Nobel en 1945, Fleming advertiu que a resistencia podía chegar a arruinar o milagre dos antibióticos. Tiña razón: nos anos 40 e 50, xa empezaron a aparecer as bacterias resistentes.
From then until the 1980s, pharmaceutical companies countered the problem of resistance by discovering many new antibiotics. At first this was a highly successful— and highly profitable— enterprise.
Desde aquela ata os anos 80, as compañías farmacéuticas fixeron fronte ao problema das resistencias descubrindo moitos antibióticos novos. Ao comezo, esta era unha empresa de éxito e moi lucrativa.
Over time, a couple things changed. Newly discovered antibiotics were often only effective for a narrow spectrum of infections, whereas the first ones had been broadly applicable. This isn’t a problem in itself, but it does mean that fewer doses of these drugs could be sold— making them less profitable. In the early days, antibiotics were heavily overprescribed, including for viral infections they had no effect on. Scrutiny around prescriptions increased, which is good, but also lowered sales. At the same time, companies began to develop more drugs that are taken over a patient’s lifetime, like blood pressure and cholesterol medications, and later anti-depressants and anti-anxiety medications. Because they are taken indefinitely, these drugs more profitable.
Co tempo, cambiaron un par de cousas. Os antibióticos que se descubrían eran a miúdo tan só efectivos para un espectro reducido de infeccións, mentres que os primeiros eran amplamente aplicables. Isto non é un problema en si mesmo, pero implica que non se podían vender tantas doses destes medicamentos, o que os facía menos rendibles. Ao comezo, os antibióticos prescribíanse en exceso, incluso para infeccións víricas sobre as que non tiñan efecto. Aumentouse o control sobre as receitas, o que é bo, pero tamén baixaron as vendas. Ao mesmo tempo, as compañías comezaron a desenvolver máis medicamentos que os pacientes toman durante toda a vida, como fármacos para a presión arterial e o colesterol, e, máis tarde, antidepresivos e medicamentos para a ansiedade. Como se toman indefinidamente, estes medicamentos son máis rendibles.
By the mid-1980s, no new chemical classes of antibiotics were discovered. But bacteria continued to acquire resistance and pass it along by sharing genetic information between individual bacteria and even across species. Now bacteria that are resistant to many antibiotics are common, and increasingly some strains are resistant to all our current drugs.
A mediados dos 80, non se descubriran novas clases químicas de antibióticos, pero as bacterias seguiron adquirindo e pasando resistencia ao compartir información xenética entre bacterias individuais e incluso entre especies. Agora é común que as bacterias sexan resistentes a moitos antibióticos, e cada vez máis cepas son resistentes a todos os medicamentos actuais.
So, what can we do about this? We need to control the use of existing antibiotics, create new ones, combat resistance to new and existing drugs, and find new ways to fight bacterial infections. The largest consumer of antibiotics is agriculture, which uses antibiotics not only to treat infections but to promote the growth of food animals. Using large volumes of antibiotics increases the bacteria’s exposure to the antibiotics and therefore their opportunity to develop resistance. Many bacteria that are common in animals, like salmonella, can also infect humans, and drug-resistant versions can pass to us through the food chain and spread through international trade and travel networks.
Entón, que podemos facer ao respecto? Necesitamos controlar o uso dos antibióticos existentes, crear outros novos, combater a resistencia aos medicamentos novos e aos existentes e encontrar novas maneiras de loitar contra as infeccións bacterianas. A agricultura é a maior consumidora de antibióticos. Úsanos non só para tratar infeccións, senón tamén para favorecer o crecemento dos animais para consumo. O uso de grandes volumes de antibióticos incrementa a exposición das bacterias a estes e, por tanto, as súas oportunidades de desenvolver resistencia. Moitas das bacterias comúns nos animais, como a salmonela, tamén poden infectar humanos, e versións resitentes poden chegar a nós a través da cadea alimentaria e estenderse polas rutas de comercio e de viaxes internacionais.
In terms of finding new antibiotics, nature offers the most promising new compounds. Organisms like other microbes and fungi have evolved over millions of years to live in competitive environments— meaning they often contain antibiotic compounds to give them a survival advantage over certain bacteria.
Respecto á busca de novos antibióticos, a natureza ofrece os compostos novos máis prometedores. Organismos coma outros microbios e fungos evolucionaron durante millóns de anos para vivir en ambientes competitivos, o que significa que, normalmente, conteñen compostos antibióticos que lles brindan unha vantaxe evolutiva sobre certas bacterias.
We can also package antibiotics with molecules that inhibit resistance. One way bacteria develop resistance is through proteins of their own that degrade the drug. By packaging the antibiotic with molecules that block the degraders, the antibiotic can do its job.
Tamén podemos deseñar antibióticos con moléculas que inhiban a resistencia. Unha maneira na que as bacterias desenvolven resistencia é mediante proteínas propias que degradan o fármaco. Ao deseñalo con moléculas que bloqueen esas proteínas, o antibiótico pode facer o seu traballo.
Phages, viruses that attack bacteria but don’t affect humans, are one promising new avenue to combat bacterial infections. Developing vaccines for common infections, meanwhile, can help prevent disease in the first place.
Os fagos, virus que atacan as bacterias pero non afectan os humanos, son unha nova vía moi prometedora para combater as infeccións bacterianas. Mentres tanto, desenvolver vacinas para as infeccións comúns pode axudar, en primeiro lugar, a previr enfermidades.
The biggest challenge to all these approaches is funding, which is woefully inadequate across the globe. Antibiotics are so unprofitable that many large pharmaceutical companies have stopped trying to develop them. Meanwhile, smaller companies that successfully bring new antibiotics to market often still go bankrupt, like the American start up Achaogen. New therapeutic techniques like phages and vaccines face the same fundamental problem as traditional antibiotics: if they’re working well, they’re used just once, which makes it difficult to make money. And to successfully counteract resistance in the long term, we’ll need to use new antibiotics sparingly— lowering the profits for their creators even further.
O maior reto para todas estas estratexias é o financiamento, que é, lamentablemente, insuficiente en todo o mundo. Os antibióticos son tan pouco rendibles que moitas grandes empresas farmacéuticas deixaron de intentar desenvolvelos. Paralelamente, as pequenas empresas que sacan novos antibióticos ao mercado acaban moitas veces crebando, coma a empresa emerxente americana Achaogen. As novas estratexias terapéuticas, coma os fagos e as vacinas, encóntranse co mesmo problema fundamental ca os antibióticos tradicionais: se funcionan ben, úsanse unha soa vez, o que dificulta gañar cartos. E, para contrarrestar con éxito a resistencia a longo prazo, necesitaremos usar os novos antibióticos con moderación, o que fará que os seus creadores teñan aínda menos beneficios.
One possible solution is to shift profits away from the volume of antibiotics sold.
Unha posible solución é facer que as ganancias non dependan
For example, the United Kingdom is testing a model where healthcare providers purchase antibiotic subscriptions. While governments are looking for ways to incentivize antibiotic development, these programs are still in the early stages. Countries around the world will need to do much more— but with enough investment in antibiotic development and controlled use of our current drugs, we can still get ahead of resistance.
da cantidade da antibióticos vendida. Por exemplo, o Reino Unido está probando un modelo no que o profesional médico compra subscricións a antibióticos. Malia que os gobernos buscan maneiras de incentivar a creación de antibióticos, estes programas están aínda nas etapas iniciais. Todos os países do mundo deberán tomar máis medidas, pero co suficiente investimento no desenvolvemento de antibióticos e o uso controlado dos fármacos actuais, aínda podemos vencer a resistencia.