Podcast: Contacting Congress, 21st Century Cures, & Antibiotics

By: Ian McLaughlin & Liana Vaccari






Antibiotic resistance, policy and prevention
By: Liana Vaccari

What are antibiotics? Antibiotics, which might also be called antimicrobial or antibacterial agents, are chemicals that can disrupt the life-cycle of bacteria in a few different ways; some actively kill the cells, others prevent them from reproducing, and others inhibit their ability to metabolize energy sources.  Over the years, they’ve been used for everything from strep throat to pneumonia1, but use has recently been dialed back because bacteria are becoming resistant to antibiotics that currently exist. One reason this has become an issue is that discoveries of new antibiotics can’t keep pace with the ability of the bacteria to resist old ones because developing new drugs is a long and expensive process.2,3
Early this year, a woman died of an infection caused by a strain of bacteria that none of the 26 antibiotics available in America could clear.4 This is pretty unusual and alarming – even if no one else is infected with the same exact strain here, the appearance of this superbug is a reminder that the antibiotics we have are vulnerable.
But how do the bacteria become resistant in the first place?3 When someone develops a bacterial infection, it’s because a strain of bacteria that can produce toxins that breakdown tissues or cause an immunological response that can be harmful (e.g. mucus build up) has set up camp in his or her body.5 The bacteria can then start doubling over relatively short times, quickly reaching thousands or millions of cells. When bacteria multiply, they basically copy genetic code from the parent cells to the next generation, but it isn’t always perfect. This is almost like when you tell stories from one generation to another, or play the game telephone. Little details get changed each time it’s told. When this happens in genes, this is called mutating, and no mutation is exactly the same from bacterium to bacterium. Mutations sometimes have no noticeable effect. Sometimes it changes in a way that renders the antibiotic less effective – maybe the cell wall is stronger and less likely to be damaged by that particular antibiotic, or maybe it had a slight change in the way the metabolism functions which is no longer as dependent on the process that was hindered by antibiotics. Some bacteria also resist death by antibiotics by producing biofilms that physically prevents antibiotics from reaching the cells. Others create enzymes that can break down the antibiotic, and others can even selectively pump out the antibiotic from inside the cell.
With thousands to millions of copies being made by the bacteria, there will inevitably be some mutants, even if not many, that are able to resist the effects of the antibiotics by one of those means. Sometimes, your infection might be cleared for the most part, with the help of both antibiotics and your own immune response, but if even a couple of these bacteria survive that were not affected by the antibiotics, now resistant to that drug, they can begin to multiply all over again until there are enough to cause a significant infection once more. You might not be as susceptible to this infection because your immune system has learned how to attack these in particular, but some of the bacteria will inevitably spread through the population and now be more resistant to the type of the antibiotic you used.
In the short term, it is to your benefit to use antibiotics right away when you have a bacterial infection. It could quickly clear your infection and return you to full health. But in doing so, you may have been host to bacteria evolving to resist that now will spread through the population, and the cheap, readily available antibiotic that you used is now less effective for other people. At some point, a doctor may have to prescribe stronger and stronger antibiotics to combat the continually mutating and proliferating bacteria which gives rise to the kind of superbug that killed the woman in Nevada. This is dangerous for you as well because in the long run, overreliance on antibiotics can make it harder for everyone to fight off infections.
This is such an issue that it has been made a priority on a national and global level. Both the World Health Organization6 and the Center for Disease Control7 are working to:
  • Prevent infections,
  • Increase awareness of antibiotic resistance and stewardship of antibiotics,
  • Track infections that do occur, and
  • Develop new drugs, diagnostics, and interventions
So what can you do to decrease the likelihood of antibiotic resistant bacteria in your own life?1-3,8-11
  • Antibiotics don’t work on viral infections which cause common colds, flu, and the typical sore throat. Strep throat is a bacterial infection that doctors test for when they swab your throat. The CDC believes that at least 30% of the time12, antibiotics are prescribed unnecessarily or inappropriately; people have used them for infections they may have been able to recover from without the drugs and in some cases, antibiotics are prescribed when they would have no effect. If you are going to take antibiotics, make sure what you have is actually a bacterial infection.
  •  If you do have a bacterial infection, take the full course of antibiotics that you are prescribed. The earlier the mutant bacteria are exposed to the antibiotics, the more likely they are to still respond, and the timeline and doses are carefully designed to kill as many as possible, even if your noticeable symptoms are gone. The earlier you stop taking the medication, the larger the population of bacteria that survives the first does.
  • On a day-to-day basis, don’t use antibacterial or antimicrobial soaps. According to the FDA, antibacterial soap is no more likely to prevent infections than regular soap, and the antibacterial additives also contribute to antibiotic resistance. This is not relevant with alcohol based hand sanitizers, but generally speaking, regularly washing your hands with normal soap and water is sufficient and effective at preventing infections otherwise spread by contact.
With these measures in mind, hopefully this appearance by a superbug in Nevada will be an isolated incident.

References:
1         Medical News Today, Antibiotics (2 January 2017), http://www.medicalnewstoday.com/articles/10278.php
3         Center for Disease Control, Drug Resistance (5 January 2017), https://www.cdc.gov/drugresistance/
4         Center for Disease Control Morbidity and Mortality Weekly Report (13 January 2017), https://www.cdc.gov/mmwr/volumes/66/wr/mm6601a7.htm?s_cid=mm6601a7_w
5         Medline Plus, Bacterial Infections (17 January 2017), https://medlineplus.gov/bacterialinfections.html
6         World Health Organization, Antimicrobial resistance (n-d), Retrieved on 15 December 2016, http://www.who.int/antimicrobial-resistance/global-action-plan/en/
7         Center for Disease Control, CDC Role (16 September 2013), https://www.cdc.gov/drugresistance/cdc_role.html
8         Medline Plus, Antibiotics (2 January 2017), https://medlineplus.gov/antibiotics.html
9         Center for Disease Control, Get Smart (14 November 2016), https://www.cdc.gov/features/getsmart/
11     Alliance for the Prudent Use of Antibiotics (n-d), Retrieved on 15 December 2016, http://emerald.tufts.edu/med/apua/about_issue/when_how.shtml
12     Center for Disease Control, Press Release (3 May 2016), https://www.cdc.gov/media/releases/2016/p0503-unnecessary-prescriptions.html

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