We live in an environment teeming with microscopic organisms. They cover not only the surfaces we touch, but also our skin and even our insides. We are not aware of this bioburden most of the time, and even if we do get the flu or if a cut gets infected, we treat it ourselves and move on without a second thought.
Some of us are not so lucky.
Because of this ever-present bioburden, individuals in hospitals are especially vulnerable to infection for three reasons.
Their immune systems are weaker.
Your immune system is made up of all the biological structures in your body that help you fight harmful germs. It is like an army, with different strategies, weapons, and strengths, all available for our system to use in the fight at any given time, depending on the power of the enemy - the invading germs. But sometimes the army is weakened. The surface barrier - the skin - could be broken by a wound, a surgical incision or a medical device. The soldiers in the immune system army, the white blood cells, could be lower than normal due to medicines or radiation, so we don't have enough soldiers to send in to battle. Simply being weak, under stress, and trying to recover from an illness or surgery is enough to compromise one's immune system. Once a person in this condition is exposed, his own army is just not strong enough to defeat the enemy alone.
They often have openings in their skin from cuts, wounds, surgery, or medical device access.
Modern medicine has made massive leaps in understanding disease and treatments since the days of bloodletting, casting spells, and bizarre medical devices. Even with our incredible advances, there are still some basic procedures that require that the body's largest organ and strongest barrier against germs - our skin - be breached by incisions. The openings allow germs to enter the body as well, and because they may stay open for long periods of time (they do not heal because the medical device is in place for a long time), the body remains open to attack at all times, even to multiple attacks from different types of bacteria.
The bacteria that survives the intensive cleaning of hospitals are more resilient and more resistant to our arsenal of weapons against them.
Out in the everyday world, a combination of our immune systems, our household soaps, and first aid medications keep bacteria at bay. In this scenario, our army against bacteria is equipped with standard jeeps, guns, and even a grenade or two. But even in the world of the hospital, where germ control is a top priority, the army is equipped with tanks, missile launchers, and nuclear bombs. Any bacteria that survives that attack and reproduces has some serious resistance. These super-armored bacteria are aptly called "superbugs" as they seem to have superpowers to survive the onslaught of bleach, repeated handwashing, antimicrobial gels, and antibacterial regimens used against them. These superpowers are actually random mutations that happened to help that microorganism survive. At the rate that microorganisms reproduce, these mutations are much more frequent than in humans.
What is the most effective way to protect the patients with compromised immune systems, open incisions, and who are surrounded by superbugs? Reducing the number of bacteria. This is partly accomplished by medical staff members washing their hands and by environmental staff cleaning the rooms. But between handwashing and between housekeeping, the remaining bacteria have plenty of time to repopulate. For this reason, innovations that kill bacteria continuously are vital to reducing the bioburden of the patient environment.