“Antibiotic resistance: the ability for a bacterium to resist the effects of a drug – the germs are not killed and the growth does not stop” – Centers for Disease Control & Prevention1
Bacteria, both good and bad, have always lived in us and on us. Some bacteria are good and help protect us from bad bacteria by outcompeting them for space and food. But sometimes, we get infected by bad bacteria through many ways including eating contaminated food, contact with a sick person, getting infected while having a lowered immune system, or through sexual contact. This often leads to disease.
When we get sick from a bacterial infection, we use antibiotics. These drugs target and kill susceptible bacteria. While antibiotics are a great form of medicine, overusing antibiotics to constantly clear out all our bacteria is not necessarily a good thing.
When we repeatedly take antibiotics, misuse antibiotics, or use hand sanitizer and other antimicrobial solutions, we clear all the susceptible bacteria, both good and bad. Clearing out all the susceptible bacteria leaves a lot of extra room for the growth of other organisms, like antibiotic-resistant bacteria.
Like susceptible bacteria, antibiotic-resistant bacteria can already live on us and they can be contracted in the ways mentioned earlier. The difference is antibiotics can’t kill them. But how do these superbugs come about?
Bacteria are always changing. They pick up DNA from their environment and they can pass it back and forth between each other, among other ways. In this manner, bacteria mutate by incorporating the DNA they pick up from the environment. If the mutation is bad for the bacterium, it dies. If the mutation is good for the bacterium, it lives and reproduces.
So if the bacterium can resist the effects of an antibiotic, this is a good mutation because it allows it to survive in the presence of the drug. Therefore, it reproduces after all the other bacteria have been killed and we then have an army of untreatable antibiotic-resistant bacteria that have plenty of room to grow, colonize, and cause serious damage.
Today, antibiotic resistance is one of the biggest health problems in the world. Doctors over-prescribe antibiotics and patients often misuse antibiotics by sharing them with friends and family or not finishing the complete dosage.
Let’s not forget that we often ingest antibiotics through other means. Half of the 50 billion pounds of antibiotics goes to treating diseases in people, but the other half is used in agriculture. Chickens, cows, pigs, and other animals are given antibiotics to prevent illness, but we’re the ones that end up ingesting these drugs2.
This all fuels antibiotic resistance! The more we clear out susceptible bacteria, including our “good” bacteria, the more room we leave for antibiotic-resistant bacteria to grow and flourish in us.
As a result, we now see methicillin-resistant Staphylococcus aureus (MRSA) in our schools, gyms, and hospitals (MRSA is resistant to the antibiotic methicillin). Multi-drug resistant tuberculosis and pneumonia pose a threat to global health. New strains of drug resistant gonorrhea have also been reported.
The economic burden of antibiotic resistant infections costs the United States health care system over $20 billion and the situation isn’t getting any better. With hardly any production of new antibiotics and resistance spreading among many strains of bacteria, the public health care system is desperately seeking a solution. The once-famed antibiotic has become nearly obsolete.
But… perhaps there is hope.
The Dubious Hero
What if we used nature against nature to fight disease? What if we don’t need to engineer new drugs to fight bacteria? What if we use something that’s been in nature longer than we have? What if we use… viruses?
But wait, viruses and bacteria together – aren’t they both bad for us?!
Actually, viruses are specific to what they attack so not all viruses can harm us. That being said, there are viruses called bacteriophages (“bacterium-eaters”) that only target bacteria and kill them.
As early as 1896, a British bacteriologist claimed antibacterial organisms in India’s Ganges and Jumna rivers were responsible for limiting cholera outbreaks. For the next 20 years, other scientists made similar observations in a variety of contexts. At the start of the 20th century, another British scientist hypothesized the antimicrobial organisms were viruses. In 1910, Felix d’Herelle spread culture on an agar plate and noticed small clearings with no bacterial growth. He called these bacterium-eating organisms ‘bacteriophages,’ or ‘phages.’
d’Herelle then took it a step further by treating humans with bacteriophages! He proved the safety of using phages by ingesting them in front of witnesses at a French hospital. He then treated four people for dysentery using phage therapy, all of which were cured within 24 hours. In 1923, Baylor College reported successful bacteriophage treatment in the United States and commented on the potential of phage therapy2.
Unbeknownst to our early scientists’ knowledge, bacteriophages are the most abundant organisms in the world, totaling at about 1030-1032 in numbers.3 Surprisingly, new phages are constantly being discovered.
They only attack specific bacteria and they replicate within them. Like most viruses, they hijack the bacterium’s machinery to make more of themselves and once they’ve finished replicating, the phages burst out, which kills the bacterium.
In this way, phages are useful because they attack the specific bacterium that needs to be eliminated. While antibiotics clear all susceptible bacteria without specifying the good from the bad, phages only kill the bad bacteria (susceptible and resistant) that they’re meant to kill. Unlike antibiotics, phages do not cause antibiotic resistance, nor do they cause allergic reactions or secondary infections.
With the discovery, marketing, and widespread use of antibiotics in the 1940’s, phage therapy became buried under the new “miracle” drug that did away with all bacteria at once. Antibiotics were “in” and there was no need for phage therapy.
Now we stand at a crossroads. Drug resistance has spread to the point of nearly tipping us into the pre-antibiotic era. Should we continue to hope for a breakthrough drug that takes years to create and billions of dollars to fund? Or should we rediscover bacteriophage therapy and study it more closely as an alternative to antibiotics?
Until we reach that decision… stay healthy!
(1) CDC (2015). Antibiotic/Antimicrobial Resistance. Centers for Disease Control and Prevention, http://www.cdc.gov/drugresistance/about.html
(2) Golkar, Z., Bagasra, O., & Pace, D.G. (2014). Bacteriophage therapy: a potential solution for the antibiotic resistance crisis. The Journal of Infection in Developing Countries, 8(2), 129-136.
(3) Balcazar, J.L. (2014). Bacteriophages as vehicles for antibiotic resistance genes in the environment. PLOS Pathogens, 10(7).
Photo Credit: xhulianmuka on Flickr