Next generation antibiotics could be turned on & off using light

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In 1st world countries, the revolution in medicine wrought by antibiotics has been largely forgotten. Before antibiotics, pneumonia had a frightening mortality rate. Syphilis killed more people than AIDS has done.

In 1988, a man in Wollongong, NSW, Australia died of a carpet burn! Why the exclamation mark at the end of the last sentence? Because in a first world country, in the antibiotic age, it normally takes an extraordinary effort of neglect for such a minor injury to lead to infection, septicemia & death.

Before antibiotics (pre World War II), prudence required that such a small abrasion be cleaned carefully with antiseptic, & then covered, to prevent entry of bacteria. If this was not done, & bacteria did enter the wound, serious, life threatening infection was possible.

Today, with antibiotics easily available, a carpet burn is likely to be ignored, until there is some sign of infection, at which point, a doctor's script would quickly solve the problem. Few would allow infection to proceed as far as happened in Wollongong in 1988.

However, there are signs that the antibiotic age may be coming to an end. Antibiotic resistance is a growing problem.

What causes antibiotic resistance? Evolution. Bacteria are capable of reproducing very quickly. Several generations in an hour. An antibiotic represents a selective force. When exposed to such a selective force, a high reproduction rate allows bacteria to evolve resistance very quickly — around 600 times faster than human beings can evolve.

Bacterial evolution of antibiotic resistance is the essential problem, but it has been exacerbated by various types of mismanagement & abuse. Every time an antibiotic is used, the risk of antibiotic resistance is created. The obvious solution is to minimize antibiotic use. Trivial uses, such as on a minor cut (or carpet burn) are not justified. Cleaning with an antiseptic & covering the wound to prevent entry of bacteria should suffice.

Other abuses include:

• routine feeding antibiotics to animals. When animals are raised in confined situations, such as feed lots, infection risk rises. Antibiotics may be routinely fed to animals as a "growth promotant". Effectiveness of such use is controversial, but is pushed by drug companies, & used by farmers.

• in some parts of the world, antibiotic use is largely or wholly uncontrolled with resultant abuse.

What can you do?

Take all the tablets! A packet of antibiotic tablets, represents a course of treatment which will eliminate the infection. It is not sufficient to take the antibiotic until signs of infection disappear. At this point, a small number of bacteria may remain, with some acquired resistance. It is important to continue treatment to eliminate such bacteria. Failure to do so may result in return of the infection in a resistant form (which is more difficult to treat), or passing it on to others.

What are the drug companies doing? Running a race. There is an ongoing race between antibiotic resistant bacteria & drug companies. One of the measures they are taking is described in the linked article:

http://www.gizmodo.com.au/2013/10/next-generation-antibiotics-could-be-turned-off-using-light/ding / continue fighting pathogens new improved antibiotics antibiotic-resistant bacterial strains threat superbugs CDC staffers current salmonella outbreak more permanent solution stubborn bacteria scientist scientists University of Groningen Holland Netherlands technique tweak tweaks prove viable idea create smart antibiotic respond light heat turn turned on off switch protect healthy bacteria unnecessary damage deactivate residual antibiotics encourage resistance antibiotics designed stick inhibit enzymes keep bacteria alive specific shape bind effectively altering shape lock and key antibiotics researchers quinolones shaped like the letter C tagged light sensitive light-sensitive molecule azobenzene blasted light heat morph letter Z waste products bacteria bulk up against antibiotics pesky side effects researchers’ researcher research researchers coaxing the antibiotics respond ultraviolet infrared light superbugs superbug super bug bugs Nature /