Bacterial resistance to antibiotics

Bacteria are everywhere: on our skin, in our throats, and the surface of our intestines. We play host to anywhere from 10,000 to 100,000 billion bacteria belonging to more than 400 different species. Fortunately, most of these bacteria do not cause infection (are nonpathogenic), but some of them do. The discovery of antibiotics to combat pathogenic bacteria marked a revolution in the 20th century. Unfortunately, because of the inappropriate use of antibiotics in human and veterinary medicine, certain strains of bacteria developed the ability to produce substances which block the action of antibiotics, or change their target or ability to penetrate cells. Bacteria develop this ability during spontaneous mutations or exchanges of genetic material. Their pathogenicity depends largely on their ability to adapt and multiply. They divide in the space of a few minutes, and each division provides a new opportunity for mutations, certain of which endow the bacteria with the ability to resist antibiotics. Resistance thus acquired is unlike bacteria's natural resistance, which is used as the basis for determining the spectrum of an antibiotic.

Impact on public health:

Following a period of time when people erroneously believed that infectious diseases had been brought to a halt thanks to antibiotics, bacteria and scientists have been in a race to outdo one another.
Resistance often concerns nosocomial infections (with the development of so-called "multi-resistant" bacteria, which are resistant to many different antibiotics and represent a difficult therapeutic challenge) but frequently it is not limited to hospital settings. Today resistance is also observed on a day-to-day basis (for example, pneumococci, which cause lung infections and otitis).
The development of such resistance also has an economic impact. For example, the drugs that are necessary to treat multi-resistant tuberculosis are almost one hundred times more expensive than the treatment used when tuberculosis responds to traditional antibiotics.
The rise in resistance may be slowed by prevention strategies based on a more careful use of antibiotics and hygiene measures taken at the individual and community level. Various initiatives have been introduced, such as the one organized by the World Health Organization, launched in 2001 to limit bacterial resistance to antibiotics and ensure surveillance.
In 2004, China issued its first national guideline on the clinical use of antibacterial medicines. The guideline sets up principles for the application of antibacterial drugs in disease treatment and prevention as well as the use of antibiotics under special pathologic and physical conditions. According to the Chinese Health Ministry, 43 percent of death cases caused by inappropriate use of medicines were related to antibacterial drugs.

Diagnosis:

The choice of the most appropriate antibiotic treatment is determined by identifying the bacteria involved and their sensitivity to various antibiotics (antibiotic susceptibility tests). Antibiotic susceptibility tests, which are traditionally performed in Petri dishes (using the so-called "diffusion" method), are increasingly performed using automated incubation systems, repeated readings and interpretation of results, which enable turnaround times to be reduced.
The surveillance of bacterial resistance to antibiotics is based on dedicated epidemiological monitoring software designed for the scale of a clinical department, a hospital, or a larger territory (a region or country).