A lot of the work that is done is preventing antibiotic resistance bacteria from spreading. They can become a huge problem in hospitals, for example. All it takes is one sick person to be admitted, and it’s possible for the bacteria in them to spread to other patients through a variety of routes. There are all sorts of new methods of sterilizing rooms and equipment, and routinely gathering samples from at-risk patients so you know early on if they’ve caught it.
There are lots of new antibiotics in development, but there are also other possible treatments being studied, such as bacteriophages. Bacteriophages are viruses that infect and kill bacteria, but aren’t dangerous for us.
Research is also being done on how, exactly, bacteria can survive antibiotics. There are a lot of mechanisms, such as the bacteria having an enzyme that changes the structure of the antibiotic, being able to “spit” the antibiotic particles out of itself faster than they can get in, or mutating so that their molecules can no longer be recognized by the antibiotic. If we know these mechanisms, it’s possible to try to develop new treatments that specifically target them.