MCQ IN MEDICINE

Detailed explanation-1: -Typical examples of ‘accidental’ pathogens include Neisseria meningitidis or Escherichia coli. Obligate pathogens require a host to fulfil their life cycle. All viruses are obligate pathogens as they are dependent on the cellular machinery of their host for their reproduction.

Detailed explanation-2: -The agents that cause disease fall into five groups: viruses, bacteria, fungi, protozoa, and helminths (worms). Protozoa and worms are usually grouped together as parasites, and are the subject of the discipline of parasitology, whereas viruses, bacteria, and fungi are the subject of microbiology.

Detailed explanation-3: -The difference between Pathogen and Parasite is easy to understand: Pathogen is an organism that causes diseases to the host after infection. Parasite is an organism that lives on or in another organism of another species. It usually derives nutrients at the expense of its host.