Bacteriophage research utilizes the ability of "phages" which are viruses that attack bacteria. Just as humans are affected by viruses such as HIV/AIDS and Influenza, bacteria are susceptible to viruses. Certain phages can be used to eliminate bacterial infections/growth very efficiently. One area in which this research is especially exciting is the treatment of bacterial "superbugs" like MRSA and other bacteria that have developed resistance to antibiotics. It is very unlikely bacteria will ever be completely phage-resistant, because as the bacteria evolves and modifies its defense to the virus, the virus will evolve alongside it. This process is similar to how influenza affects the human population each year, developing different strains to which human immune systems are vulnerable.