Antibiotic resistance is the ability of microorganisms or bacteria to survive the effects of antibiotics and continue to reproduce. We distinguish two basic types of antibiotic resistance:
- Natural (primary) resistance: Bacteria exist which have a natural resistance against penicillins which occur in nature or other antibiotics. For example, cephalosporin has no effect against the bacterial genus Enterococcus and ampicillin not against Pseudomonas aeruginosa.
- Acquired (secondary) resistance: Here, bacteria become resistant against antibiotics which they are originally susceptible to. Some scientists and doctors assume that secondary resistances to most therapeutic antibiotics have already emerged, i.e. many drugs will neither prophylactic nor in emergencies have the desired effect.
Routine and in many cases excessive, unnecessary, thoughtless, and ineffective prescription and administration of antibiotics is generally thought to be one reason for the proliferation of antibiotic resistance. For most colds, for instance, antibiotics are neither needed nor practical – they only work against bacterial infections, but remain ineffective against the viral infections we frequently suffer from. In many cases, patients fail to follow instructions when taking antibiotics, which results in pathogens not being completely destroyed, reproducing, and becoming resistant against the agent. Use of antibiotics in meat production is also considered to contribute to the development resistances.