Final answer:
The pathogen's response to antimicrobics is determined by factors such as target modification, resistance development, and the type of antimicrobial drug (bacteriostatic or bactericidal). Selective toxicity and the host's immune system also play roles in treatment effectiveness.
Step-by-step explanation:
Factors that determine the pathogen's response to various antimicrobics include the pathogen's ability to undergo target modification, which involves structural changes to the microbial targets of the drugs. The potency and range of the antimicrobial activity, as well as the pathogen's ability to develop resistance through chromosomal mutations or horizontal gene transfer, are also critical. Furthermore, the nature of the antimicrobial, whether it is bacteriostatic or bactericidal, its spectrum of activity, and the drug's selective toxicity are important considerations when selecting an antimicrobial drug.
Antimicrobial drugs that demonstrate bactericidal properties will kill the target bacteria, whereas bacteriostatic drugs only inhibit growth, allowing for the immune system to clear the infection. The use of narrow-spectrum antimicrobial drugs is preferred when the pathogen is known, to minimize damage to normal microbiota and resist the development of antimicrobial resistance. Lastly, host factors such as the individual's immune defenses also play a role in the effectiveness of antimicrobial treatments.