A fungus that can infect both healthy and immunocompromised patients is called
a(n)
a. true pathogen
b. opportunistic pathogen
c. commensal organism
d. symbiotic organism

Verified step by step guidance

1. Understand the definitions of each term provided in the options.
2. A 'true pathogen' is an organism that can cause disease in healthy individuals as well as those who are immunocompromised.
3. An 'opportunistic pathogen' typically causes disease in individuals with weakened immune systems but not in healthy individuals.
4. A 'commensal organism' lives on or within a host without causing harm, often benefiting from the host.
5. A 'symbiotic organism' is involved in a relationship where both organisms benefit, or one benefits without harming the other.

Key Concepts

True Pathogen

A true pathogen is an organism that can cause disease in a healthy host with a normal immune response. These pathogens possess virulence factors that enable them to invade and damage host tissues, leading to illness. Examples include bacteria like Streptococcus pneumoniae and viruses like influenza virus.

Opportunistic Pathogen

Opportunistic pathogens are microorganisms that typically do not cause disease in healthy individuals but can lead to infections in those with weakened immune systems, such as the elderly, infants, or immunocompromised patients. Common examples include fungi like Candida and bacteria like Pseudomonas aeruginosa, which can exploit vulnerabilities in the host.

Commensal and Symbiotic Organisms

Commensal organisms live on or in a host without causing harm, often providing benefits such as aiding digestion or protecting against pathogens. Symbiotic organisms engage in a mutually beneficial relationship with their host. While both types of organisms are generally non-pathogenic, they can become harmful under certain conditions, particularly in immunocompromised individuals.