An­tibi­otic re­sis­tance – a se­ri­ous threat to health


AN­TIBI­OTICS have been one of the big­gest sci­en­tific ad­vances in the past cen­tury, as sig­nif­i­cant in the vet­eri­nary world as in the hu­man med­i­cal sphere.

Back in 1928, Alexan­der Flem­ing was ex­am­in­ing petri dishes used for bac­te­rial cul­tures in his lab­o­ra­tory when he came back from hol­i­days. He no­ticed that there were gaps in the growth of bac­te­ria around patches of mould growth. “That’s funny” he fa­mously re­marked, and he went on to iso­late the chem­i­cal pro­duced by the mould, nam­ing it “peni­cillin”.

It took over fif­teen years for peni­cillin to be mass pro­duced and dis­trib­uted to doc­tors and vets, with the dis­cov­ery rev­o­lu­tion­is­ing the treat­ment of dis­eases. Age-old scourges of mankind, in­clud­ing syphilis, gan­grene and tu­ber­cu­lo­sis, could fi­nally be cured with ease. Many other mi­nor ill­nesses – such as throat in­fec­tions – could now be cured. Com­plex surgery be­came pos­si­ble with­out the fear of post-op­er­a­tive in­fec­tions dam­ag­ing the pa­tient.

Many other an­tibi­otics were dis­cov­ered in the decades af­ter peni­cillin, pro­vid­ing back up for the rare cases when peni­cillin failed. It seemed that mankind had fi­nally de­feated one of the big­gest threats to hu­man health: in­fec­tious dis­eases caused by bac­te­ria.

From the start, it had been clear that some bac­te­ria were re­sis­tant to an­tibi­otics, but this did not seem to mat­ter too much. New an­tibi­otics were be­ing dis­cov­ered or in­vented at a rapid rate, so it was easy to move on to a bet­ter, stronger an­tibi­otic if the first one didn’t work. But from the early 1960’s, the sit­u­a­tion be­gan to ap­pear bleaker. Bac­te­ria were found to be able to pass their re­sis­tance on, so that if one strain de­vel­oped re­sis­tance, this could be passed on to other bac­te­ria.

At the same time, as the decades passed, the rate of dis­cov­ery of new an­tibi­otics be­gan to slow. Since the early 1980’s, phar­ma­ceu­ti­cal com­pa­nies have fo­cussed more on other drugs (such as statins) that are seen to be more prof­itable.

The com­bi­na­tion of more re­sis­tant in­fec­tions com­bined with fewer new “bet­ter” an­tibi­otics has led to the cur­rent cri­sis. In the past, re­sis­tant in­fec­tions were as­so­ci­ated pre­dom­i­nantly with hos­pi­tals, care homes and vet clin­ics, but over the past decade, they are in­creas­ingly be­ing found in the wider com­mu­nity as well.

An­tibi­otic re­sis­tance, like global warm­ing, is now an im­mense threat to our fu­ture. If the drugs lose their ef­fec­tive­ness, key sur­gi­cal pro­ce­dures (such as or­gan trans­plants, in­testi­nal surgery, cae­sarean sec­tions and joint re­place­ments) and im­por­tant med­i­cal treat­ments that sup­press the im­mune system (such as chemo­ther­apy for can­cer) will be­come too dan­ger­ous to per­form. Fur­ther­more, life threat­en­ing in­fec­tious dis­eases such as pneu­mo­nia, TB, HIV and malaria will again be­come com­mon. At the mo­ment, 700,000 hu­man deaths hap­pen ev­ery year due to an­tibi­otic re­sis­tance. If cur­rent trends con­tinue, by 2050 this will reach a fig­ure of 10 mil­lion deaths ev­ery year; more peo­ple than cur­rently die from can­cer. The eco­nomic cost is equally shock­ing, with tril­lions of euro spent on wasted an­tibi­otics that don’t work and pay­ing for the re­sult­ing med­i­cal out­comes.

So what can be done to solve this prob­lem? A ma­jor re­port pub­lished last week makes ten rec­om­men­da­tions, and global gov­ern­ment ac­tion is needed to put th­ese into place. Th­ese in­clude ma­jor pub­lic aware­ness cam­paigns, in­cen­tives to do re­search to de­velop new an­tibi­otics, and im­por­tantly, us­ing an­tibi­otics more spar­ingly in hu­mans and an­i­mals. By 2020, the aim is for it to be com­pul­sory that the pre­scrip­tion of an­tibi­otics can only be al­lowed if there is data to sup­port the choice.

At the mo­ment, vets use an­tibi­otics if they have a clin­i­cal im­pres­sion that they are needed (for ex­am­ple, if a dog has a high tem­per­a­ture with bloody di­ar­rhoea). And we choose the an­tibi­otic which we know, from ex­pe­ri­ence, is most likely to work. In the fu­ture, we may only be al­lowed to use an­tibi­otics if we have done spe­cific tests on the dog (e.g. bac­te­rial cul­tures) that prove that they are ap­pro­pri­ate. At the mo­ment, it takes at least 48 hours to carry out such tests, but the re­port ad­vises that new, rapid, tests need to be de­vel­oped to re­move this time lag.

Vet­eri­nary use of an­tibi­otics falls into two main ar­eas: farm animal use, and com­pan­ion animal use, which mostly means pets. The re­duc­tion of an­tibi­otic use on farms is a sig­nif­i­cant rec­om­men­da­tion in the re­port, be­yond the scope of this “pet vet” col­umn. But com­pan­ion animal vets use an­tibi­otics ev­ery day, and we need to ex­am­ine our own roles in this area. Our aim, as vets, is to cure our pa­tients as rapidly as pos­si­ble, with the small­est risk of treat­ment fail­ure. With this in mind, it’s easy to see why we are quick to use strong an­tibi­otics for in­di­vid­ual pa­tients. We jus­tify this as the best way of look­ing af­ter animal wel­fare, and it’s what own­ers want for their own pets. But do we need to look harder at the big pic­ture?

Should we keep an­tibi­otics as a sec­ond string to our bow, only for those cases of sore throats, itchy skin and ears, and up­set di­ges­tive sys­tems when a non-an­tibi­otic choice has failed? An­tibi­otic re­sis­tance is a big chal­lenge for my pro­fes­sion, and in­deed for pet own­ers.

Do prob­lems like mi­nor in­fected cuts re­ally need an­tibi­otics?

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