Resistance means a reduced or no response of a germ to an antibiotic, although scientific experience shows that this antibiotic would have to destroy the germ. At the beginning of the age of antibiotics, resistance was largely unknown. This was because the majority of the population had never come into contact with an antibiotic before.
When the bacterium and antibiotic came into initial contact, the drug was able to kill the pathogen quickly and reliably. Nowadays, there is hardly a person who has not taken an antibiotic at least once. Most pathogens have also come into contact with an antibiotic.
Many bacterial strains are still developing mechanisms that ensure that the antibiotic, which is otherwise so harmful, can no longer harm them. One mechanism is the so-called mutation. If an antibiotic acts, for example, by inhibiting an enzyme and if this enzyme is converted (mutated) by the bacterium at the molecular genetic level, the antibiotic can no longer have sufficient effect.
Antibiotics which only have one point of attack in the bacterium (e.g. macrolide such as erythromycin) are particularly susceptible to resistance. The main cause of a development of resistance is seen on the one hand in an early discontinuation of therapy and on the other hand in a hasty use of antibiotics. Studies report that every second doctor prescribes antibiotics even if it is not a bacterial but a viral infection.
In countries where antibiotics are freely available in supermarkets, the resistance rate increases significantly. In Germany, there is a 7-8% resistance to penicillin. In countries such as Spain or Taiwan half of the germs are already resistant.
The danger is that under certain circumstances no reserve drugs are effective (e.g. macrolides in the case of penicillin resistance) and that diseases requiring urgent treatment can no longer be treated. E. coli bacteria are 30% resistant to doxycycline and cotrimoxazole. 10% of the dangerous pneumococci, 50% of the urinary tract infection germs E. coli are resistant to the former standard drug amoxicillin. For this reason, there are also combined preparations of amoxicillin with clavulanic acid. Here, the clavulanic acid ensures that the resistance mechanism of the bacterium is eliminated.
Development of new drugs
For some time now, new antibiotic groups have been on the market, which are mainly used in the treatment of germs that have become resistant. Ketolide (telothromycin) has been approved for the treatment of infections of the upper and lower respiratory tract since 2001. They act by inhibiting the protein synthesis of bacteria that are located on the so-called ribosomes.
The oxalidinones act by inhibiting the protein synthesis of the bacteria at a very early stage. Resistances have not yet been described. The main areas of application are pneumonia, skin and soft tissue infections with severe courses.