Imagine Magazine - Johns Hopkins - January/February 2016 - (Page 16)

Slowing the Race ADDRESSING ANTIBIOTIC by Ramanan Laxminarayan, Ph.D., M.P.H. I n 1924, President Calvin Coolidge's 16-year-old son developed a blister on his foot after a game of tennis. A few days later, he died of a bacterial infection. Most of us don't remember a time when a simple cut could be fatal. We grew up in a world with antibiotics. These drugs have saved millions of lives and transformed global health. Because of them, we rarely die of infections. We can have transplants; we can have surgeries that require the human body to be kept open for long periods of time without the risk of infection. They are really the basis on which modern medicine rests. Antibiotics work by killing off bacteria that are susceptible to them. The bacteria that survive treatment are not susceptible to the drug or are "drug-resistant." It's a basic evolutionary phenomenon. Over time, as we've used these drugs, the populations of bacteria in our bodies and in the environment have become increasingly drug-resistant. To make things worse, bacteria have the ability to share genetic material via DNA strands called plasmids. Completely unrelated bacteria can share plasmids. Thus, even bacteria that have not been exposed to an antibiotic can acquire resistance genes from other bacteria. Antibiotic resistance occurs naturally, but our misuse of antibiotics in humans and animals has vastly accelerated the process. The CDC estimates that up to half of all human antibiotic use is unnecessary or inappropriate. This includes giving antibiotics inappropriately-for example, for treating a cold or flu, even though those are viral, not bacterial, infections and do not respond to antibiotics. It also includes the common practice of feeding antibiotics to livestock to make them grow more quickly, because bacteria that have developed drug resistance in animals can be transmitted to humans. The massive use of antibiotics around the world has created antibiotic resistance that is a growing global public health problem. Fifteen years ago, 5-15% of bacteria were resistant to some or all antibiotics; today, it's 15-50%. This evolutionary race we are in with bacteria is not a race we can win: Bacteria can evolve and reproduce much more quickly than we can develop new drugs. We have to find ways to slow the race. 16 imagine A Problem of the Commons Unfortunately, many economic forces encourage behaviors that drive the evolution of drug resistance. Doctors wanting to be responsive to their patients' wishes may prescribe antibiotics even when they are not warranted, such as in cases of the flu. Companies that sell antibiotics want to maximize profits, and this drives them to promote, not restrain, their drugs' use. These things may be true about many drugs; however, there is something fundamentally different about antibiotics. My taking a drug to treat high blood pressure, for example, will not diminish its effectiveness for others. But my using an antibiotic contributes to the global population of antibiotic-resistant bacteria, and so can reduce the drug's effectiveness in the future, for me and for others. This is a case of what economists call a problem of the commons. There are resources that we all use ("commons"), like the air and the oceans. When we use one of these resources, our actions can have consequences for others. The problem is that those using a common resource according to their own self-interest may deplete or pollute that common resource, and so act in a way that is contrary to the best interests of all. Antibiotic effectiveness is such a resource. It's not a typical resource, because it's not the supply of antibiotics that will run out-it's their effectiveness. But it is a resource we all benefit from, and one that can be used up. Jan/Feb 2016

Table of Contents for the Digital Edition of Imagine Magazine - Johns Hopkins - January/February 2016

Big Picture
In My Own Words CDC Director Tom Frieden, M.D., M.P.H.
My Summer of Medicine Three ways of exploring healthcare
Teens Target: Public Health How high school students are solving real-world public health problems
Slowing the Race Addressing antibiotic resistance
For the Greater Good Majoring in public health
Epic Epidemics Studying History of Disease at CTY
Teen Health is Public Health Interview with Beth Marshall, Associate Director, Center for Adolescent Health at the Johns Hopkins Bloomberg School of Public Health
Building Bridges Addressing health disparities through service
Becoming a Disease Detective Behind the scenes at the CDC
Finding Light in the Darkness Astrophysics at UCSC SIP
Girls Who Code Paving the way to careers in tech
Selected Opportunities and Resources
Off the Shelf Review of Iris Chang’s The Chinese in America
Word Wise
Exploring Career Options Interview with epidemiologist Christine Scott-Waldron, M.S.P.H.
One Step Ahead Summer in limbo
Planning Ahead for College Is medical school in your future?
Students Review: Tufts University
Creative Minds Imagine Essay contest winners
Mark Your Calendar
Knossos Games

Imagine Magazine - Johns Hopkins - January/February 2016