organized curiosity

Improving health care through research

Reversing the trend of antimicrobial resistance

Leave a comment

There are few medical discoveries that have changed the course of human history more than antibiotics.  Prior to the serendipitous discovery of penicillin in 1928 a pneumonia was fatal in over 35% of infections and a simple cut leading to a skin infection would kill over 10% of people.  Since the development of antibiotics, now less than 10% of people die from pneumonia and death from skin infections are uncommon.  These miracles of modern medicine have been so successful, that by the late 1960’s physicians and policy makers were declaring victory in the war against bacteria.

Yet nature hates a void and more importantly is more clever than we will ever be.  Within 3 years of its discovery, bacteria developed resistance to penicillin. Since 1928 we have seen the introduction of multiple different classes of antibiotics, each having had the promise of protecting us from even the nastiest of bacteria.  Yet not long after each antibiotic has been introduced, the bacteria have found ways to resist its killing potential.  And where has that left us?  We now have an antimicrobial resistance (AMR) problem that has been declared a global heath emergency. Antimicrobial resistant organisms (AROs) now cause over 2 million infections and kill 23,000 people in the US each year costing 20 billion dollars in excess health care costs and over 30 billion dollars in lost productivity.  Infections like gonorrhoea (one of the Center for Disease Control in Atlanta’s three most urgent threats) were once easily treated but have become so resistant that we soon may not have any treatment options.2 In addition, the overuse of antibiotics and the elimination of “good bacteria” from our bowels have left an opening (remember nature hates a void) for opportunistic pathogens like clostridium difficile diarrhoea (the second of the CDC’s top three urgent treats), leading to increased health care cost due to prolonged hospitalizations or more dramatically, loss of your colon or death.

So how did this happen? It is a complicated problem and we have a complicated relationship with antimicrobials.  There is no question antibiotics save lives.  As we advance our ability to prolong life through toxic combinations of drugs to kill cancer or suppressing our immune systems to allow a life saving transplant to flourish, we modify the human hosts ability to fight infection increasing our reliance on antibiotics. But it is the inappropriate use of antibiotics that is probably the biggest driver of resistance.

In medicine we want to help patients and as patients we often want a pill to make us feel better.  For example, the vast majority of sore throats (and most other upper respiratory tract infections) are due to viral infections.  Antibiotics have absolutely no activity on viruses, yet antibiotics are often requested and prescribed for sore throats.  However, taking these antibiotics pressures the bacteria that normally live in you body to evolve, and adapt to survive in the presence of a chemical designed to kill them. Just as important, many of the genetic changes behind resistance can be transmitted from one bacteria to another. Bacteria can collect many different resistance genes, so eventually they have a full set that protects them from all different types of antibiotics.  In Canada you need a prescription to get antibiotic.  However in other regions of the world, antibiotic are freely available over the counter which leads to indiscriminate and inappropriate use.todd-hatchette

AMR is also the result of antibiotic use outside medicine.    We use tons of antibiotics in agriculture which is added to the feed of animals to can keep them healthy and increase production.  However, this leads to the evolution of resistance in bacteria living in these animals, which can cause infections in humans or transfer their resistance genes to other bacteria that commonly infect humans.  In addition, AMR can be an unintended consequence of obsession to ensure everything we own is clean and sterile.  We impregnate our plastic toys with triclosan to reduce bacterial contamination with the goal of making them safer. However, this chemical can turn on antibiotic resistance genes in bacteria so rather than preventing infection we are creating the potential for infections that are harder to treat.

AMR also reflects the new global reality.  We live in a global village where you can travel halfway around the world in a day. We also have a form of medical tourism where people travel to places like India for surgical procedures they cannot get in North America. AROs that develop in one region can hitch a ride on returning travellers where they can be transmitted to people within local hospitals.

So how do we address this problem?  We need to do a better job of identifying these infections and ways to prevent transmission. In the hospital AROs are transmitted to patients on the hands of health care workers. In short we need to wash our hands.  Clearly it is not just that simple. Antimicrobial stewardship programs need to be instituted in all health care settings.  We need to track resistance and we need to change how we use antibiotics. We need to use the narrowest spectrum antibiotic needed for the shortest time necessary to cure the infection.  We also need to promote the development of new antibiotics to deal with these resistant infections.  This is a challenge because it takes 10 years and billions of dollars to bring a new drug to market and how can a business lobby their share holders to back a drug which has restricted use and therefore a restricted market.  However, we need them and as importantly we need to reserve these drugs for resistant infections and not use them indiscriminately.

What can you do?  Remember that not every sniffle, cough or sore throat requires an antibiotic. Similarly if your physician suggests you need it, question why to make sure you really do.  When you do make sure to take them as directed. Global consumption of antibiotics has increased 40% in the last year. Recent modeling suggests that if this disturbing trend is not reversed, by 2050 AMR infections will surpass cancer as the number one cause of death and cost the world economy 100 TRILLION dollars. But if we take action now and work together we can ensure we do not regress into a pre-antibiotic era of medicine where physicians watch helplessly as people die from infections that should be treatable.

~Dr. Todd Hatchette

Advertisements

This account is not checked regularly.

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s