MCQ IN MEDICINE

Detailed explanation-1: -Infectious diseases are caused by pathogens, which include bacteria, fungi, protozoa, worms, viruses, and even infectious proteins called prions. Pathogens of all classes must have mechanisms for entering their host and for evading immediate destruction by the host immune system. Most bacteria are not pathogenic.

Detailed explanation-2: -What is a pathogen? A pathogen is defined as an organism causing disease to its host, with the severity of the disease symptoms referred to as virulence. Pathogens are taxonomically widely diverse and comprise viruses and bacteria as well as unicellular and multicellular eukaryotes.

Detailed explanation-3: -Pathogens include viruses, bacteria, fungi, and parasites that invade the body and can cause health issues. Anthrax, HIV, Epstein-Barr virus, and the Zika virus, among many others are examples of pathogens that cause serious diseases.

Detailed explanation-4: -A microorganism is only considered a pathogen if it causes disease. Harmless viruses, bacteria, fungi, protozoa, and parasites are simply called microorganisms.