HLTH 320 Exam #2 Review: Infectious Diseases, Virology, and Diagnostics

Vocabulary practice flashcards covering disinfection, Tuberculosis (Mtb) pathogenesis, viral replication cycles, antiviral mechanisms, Poliovirus, Smallpox, and SARS-CoV-2 concepts from the HLTH 320 Exam #2 Review Guide.

Antiseptic

A chemical agent applied directly to living tissue (such as skin) to destroy or inhibit microorganisms, distinguished from a disinfectant which is applied to inanimate surfaces.

Granuloma

An organized aggregate of immune cells formed in the lungs during a latent Mtb infection to wall off the bacteria; rupture of this structure releases active bacteria and causes spreading disease.

Virion

The complete, infective form of a virus outside a host cell, consisting of a nucleic acid core (RNA or DNA) enclosed within a protein capsid, and in some cases, an outer lipid envelope.

Enveloped Virus

A virus surrounded by an outer lipid bilayer membrane derived from host cell membranes; it is more sensitive and fragile in the outside environment because lipid envelopes are easily disrupted by heat, drying, and detergents.

Non-Enveloped Virus

A virus that lacks an outer lipid bilayer and is enclosed only by its protein capsid, rendering it more stable and resistant to environmental extremes, drying, and chemical agents.

Absorption

The initial step of the viral replication cycle defined as the attachment of the virion to the host cell surface receptors.

Penetration

The step in the viral replication process in which the viral genetic information enters the host cell.

Replication

The phase of viral reproduction in which the host cell's machinery is utilized to create viral components, including nucleic acids and viral proteins.

Assembly

The stage in the viral replication cycle where newly synthesized viral components are put together into new, complete virions.

Release

The final stage of the viral cycle wherein mature virions exit the host cell, which happens through host cell lysis or budding.

Lytic Life Cycle

A viral life cycle in which the virus rapidly hijacks host cell machinery, replicates viral progeny, and lyses (destroys) the host cell to release new virions.

Lysogenic Life Cycle

A viral life cycle in which viral genetic material integrates into or persists stably within the host cell genome without immediate production of progeny or destruction of the host cell.

Productive Infection

A viral infection in host cells that culminates in the successful production and release of infectious viral progeny.

Nonproductive Infection

A viral infection where the virus infects a host cell but does not result in the generation or release of new infectious progeny virions.

Goal of Antiviral Drugs

Therapeutic compounds designed to impair a specific virus and inhibit viral replication mechanisms without harming human host cells.

Confluency

The degree to which smallpox lesions merge together on the skin; confluent eruptions across large skin areas correlate with significantly higher mortality rates compared to discrete lesions.

Variolation

An early method of immunization against smallpox involving the deliberate inoculation of material taken from a smallpox lesion into a healthy individual, carrying higher morbidity and mortality risks than vaccination.

Salk Vaccine

An inactivated (killed) poliovirus vaccine administered by injection that induces systemic IgG antibodies and protects against paralytic disease without risk of viral reversion.

Sabin Vaccine

An oral, live-attenuated poliovirus vaccine that induces strong mucosal IgA and systemic immunity, but carries a small risk of reverting to neurovirulence (vaccine-derived poliovirus).

Spike Protein

A surface glycoprotein that mediates viral attachment by specifically binding to host cell receptors, facilitating entry into human host cells.

NAAT (Nucleic Acid Amplification Test)

A molecular diagnostic technique (such as RT-PCR) that amplifies and detects viral genetic sequences, providing high diagnostic sensitivity and specificity.

Antigen Test

A diagnostic immunoassay designed to detect specific viral surface proteins; it is faster and cheaper than NAAT but typically less sensitive.