Up until our recent past and the 1928 discovery of penicillin by Alexander Fleming, bacterial infections were responsible for the deaths of untold numbers of people. Since that point, antibiotic advancements have saved many, many lives. However, as with many good news stories, there is often a dark side and in this case, that dark side has been our unintentional breeding of a much stronger enemy.
For those who might deny evolution, concrete proof is quite visible in the form of antibiotic resistance developed by the 'bugs' over the last 80 years. The bacteria that attack us are constantly being exposed to antibiotic compounds as we try to eradicate them when they infect us. However, as the old cliche goes, "What doesn't kill you, makes you stronger", so the few tough bugs that survive a given drug attack pass on their "survival techniques" to future generations and thus make our antibiotics less and less effective over time.
Seeing the growing resistance of the bad bugs against our drugs, researchers have been seeking news ways to combat them. While development of new drugs is the most obvious way to stay ahead of the bugs, other techniques are also being investigated. One important group of techniques involves making surfaces inhospitable or downright deadly to the bacteria and other increases the effectiveness of removing those bacteria that do get a foothold.
An example of an inhospitable surface is Sharklet Technologies' development of a microscopic, diamond-shaped, surface pattern modeled after the texture of shark skin. The texture does not attack the bacteria chemically, but simply forms a surface for which attachment by the bacteria is difficult. In a similar vein, the thin films created by researchers in the Materials Science and Engineering faculty at MIT also show an ability to control how well bacteria can adhere to the surfaces. In this case, the controlled stiffness of the film is what provides the ability to limit the bacteria's ability to adhere.
Both of these surfaces can be applied to various medical devices and commonly contacted surfaces. Unlike drugs that kill the bacteria and risk an increase in resistance over time, these surfaces simply limit the number of bacteria on the medical equipment in contact with or inside patients. They also have the added benefit of not being toxic to patients as some drugs would be.
A last example in the creation of inhospitable surfaces involves efforts from Syracuse University to create chemicals that may be applied to surfaces to prevent bacteria from using specific proteins to adhere to the surface. Like the previous techniques, the application of the chemicals does not kill the bacteria, but makes it difficult for them to adhere and accumulate. From the results of the research, these surface chemicals could prevent bacteria from adhering four times as long as some other methods. However, whether the surfaces might be toxic to humans was unclear.
Continuing from inhospitable surfaces to deadly ones, the work led by the University of Bath, but including scientists from several European countries is creating chemicals that can be applied to surfaces and will kill bacteria that come into contact with the surface. The compounds being created have contained zinc, copper and silver, but have been checked to ensure no toxicity to human cells. These compounds have been found to be effective against the often fatal super-bug Methicillin-resistant Staphylococcus aureus commonly known as MRSA or antibiotic resistant "staph" bacteria.
A last improvement in technology related to keeping surfaces clean involves new techniques for scouring those surfaces on which bacteria have already established themselves. While it would be ideal to prevent all bacterial accumulation on surfaces, the reality is that some bacterial will always find a home where they are not wanted so we still need ways to evict them.
Ultrasonic cleaners are commonly used in hospitals to sterilize equipment and work on the basis of cavitation or the collapse of tiny air bubbles within a liquid. The application of ultrasound or high frequency sound waves to a liquid causes that liquid to develop millions of short-lived bubbles whose collapse is very destructive to bacteria within the liquid and on the surface of objects being cleaned within the liquid.
The new technique developed by the UK National Physical Laboratory (NPL) to improve ultrasonic cleaning involves listening to the sound of the collapsing bubbles within the liquid. Listening to these popping bubbles allows an ultrasonic cleaner to ensure that the right amount of sound energy is being applied to kill the bacteria and remove them from the object surfaces being cleaned. This is a significant improvement in ultrasonic cleaners as it removes the need for trial an error that has been used up to this point.
While some of the new technologies mentioned may at some point result in resistant bacteria, they offer to at least move the battleground for fighting the bacteria outside of our bodies. Their combined use offers the chance to reduce the rate of super bug infection in hospitals significantly and could save the lives of many vulnerable patients. At a minimum it provides a plan when the bad bugs come for you.