The human race is fighting a losing a war between us and creatures of miniscule size. Bacteria have always been our microscopic enemies, threatening our health for millennia. For most of history we had no way to fight them other than hoping our immune systems were up to the task. The discovery of penicillin in 1928 changed all of that.
Armed with penicillin and all the subsequently discovered antibiotics, we finally had an effective weapon. A bacterial infection was no longer a death sentence. Over the next 90 years, antibiotics would be used to save millions of lives. Unfortunately though, our new miracle drug came with a heavy price tag.
Bacteria, over the years, have evolved stronger and more complex resistances to our antibiotics. A distressingly high number of bacteria have now become resistant to all known antibiotics. According to a report from the United Nations Foundation and the Wellcome Charitable Trust, “drug-resistant infections cause around 700,000 deaths worldwide each year.” That number is expected to more than double by 2050.
Researchers and scientists are searching desperately for anything that could help us fight these infections. Many scientists are now looking to the past for answers. Almost a hundred years after their discovery, bacteriophages are coming back into the spotlight in the hopes that they will be able to combat what antibiotics no longer can.
A bacteriophage is a virus that infects and kills bacteria. They are composed and built the same as viruses that infect us but with several key differences. They only infect bacteria. The significant aspect of phages though, is their high specificity. Phages are designed to target one distinct species of bacteria. Each different type of phage will only target its specific bacteria. This specificity is achieved using highly specialized receptors. The receptor on the phage will match only to the receptors on a select type of bacteria. This guarantees that the phage will only infect that bacteria as the phage will be unable to bind to receptors on different cells.
As all human cells carry a very different set of receptors to bacteria, this renders them essentially immune to phages.
The hope for phage therapy is that it will be able to overcome antibiotic resistance. A patient with a bacterial infection that is resistant to all known antibiotics could be treated relatively easily with phages. When a patient presents with a resistant bacterial infection, they would be administered a cocktail of focused phages. The phages would circulate, target, and kill the bacteria, thus defeating the infection. Since the phages would have no effect on any other cells, all side effects associated with antibiotics would be eliminated.
There are still downsides to bacteriophages. The biggest one being we simply do not know enough about them yet. There are too many unanswered questions. We need a better understanding of how they would interact with our bodies and bacteria flora and fauna before implementing the therapy on a large scale.