NCM 118 — Communicable Disease, Viral Diseases & Sexually Transmitted Infections

A collection of vocabulary terms covering concepts of communicable diseases, immunology, viral infections (Measles, Mumps, Rabies, Rubella, Ebola, etc.), and sexually transmitted infections based on NCM 118 lecture notes.

Animal Host

An organism that provides living conditions to support a microorganism.

Bacterial Load

The number and type of microorganisms contaminating an object or organism.

Carrier

A person who has an organism without apparent signs or symptoms and can transmit infection.

Communicable Disease

Illness resulting from infection, presence, and growth of pathogenic biologic agents in a human or animal host.

Contagious Disease

A disease spread from person to person in several ways, including direct physical contact.

Disinfection

Cleaning something, especially with a chemical, to destroy bacteria.

Epidemic

A sudden outbreak of disease in a certain geographical area.

Fumigation

Disinfecting or purifying an area using chemical fumes.

Prevalence

The condition or act of being prevalent; commonness.

Quarantine

A state, period, or place of isolation for people or animals arriving from elsewhere or exposed to infectious disease.

Reservoir of Infection

A person, plant, animal, substance, or location that provides living conditions for microorganisms and enables their dispersal.

Inapparent Infection

An infection where the person never or only mildly develops illness but can transmit it.

Incidence

The occurrence, rate, or frequency of a disease.

Incubation Period

The period between exposure to an infection and appearance of the first symptoms.

Infectious Disease

A disorder caused by organisms.

Airborne Transmission

Transmission through droplet nuclei that remain infectious while suspended in air over distance and time.

Viral Load

The amount of virus in an infected person's blood.

Natural Immunity

Immunity present at birth that provides broad-spectrum defense against infection.

Acquired Immunity

Immunity that develops after birth following exposure to an antigen or disease.

Cell-mediated Response

An immune response involving T-cell activation.

Effector Mechanisms

Immune processes involving B-cell maturation and antibody production.

Natural Active Adaptive Immunity

Immunity resulting from natural exposure to an antigen.

Artificial Active Adaptive Immunity

Deliberate introduction of an antigen to stimulate the immune system, such as vaccination.

Natural Passive Immunity

Transfer of antibodies from mother to child through the placenta or breast milk.

Artificial Passive Immunity

Artificial introduction of antibodies from immune animals or humans, providing immediate protection.

Lysozymes

Enzymes found in tears, saliva, nasal secretions, and sweat that lyse cells and help prevent microbial growth.

Histamine

A chemical mediator causing vasodilation, increased vascular permeability, gland secretion, bronchial smooth-muscle contraction, and eosinophil attraction.

Kinins

Substances that cause vasodilation, increase vascular permeability, stimulate pain receptors, and attract neutrophils.

Interferons

Proteins that interfere with viral production and infection.

Complement

A system that increases vascular permeability, releases histamine, activates kinins, lyses cells, promotes phagocytosis, and attracts immune cells.

Neutrophils

Phagocytic cells that are usually the first to enter infected tissues to initiate inflammation.

Macrophage

The most effective phagocyte, formed after a monocyte enters tissues.

Natural Killer Cell

A cell that lyses tumor and virus-infected cells.

Memory B Cells

Cells that provide a quick and effective response to a previously encountered antigen.

Cytotoxic T Cells

T lymphocytes that destroy cells through lysis or cytokine production.

Helper T Cells

T lymphocytes that activate B cells and cytotoxic T cells.

Chain of Infection Links

The sequence of infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host.

Prodromal Period

The period between the end of incubation and appearance of characteristic symptoms.

Clinical Illness Period

Stage of rapid multiplication of the pathogen with exponential growth and peak population.

Convalescence Period

The period when the host gradually recovers from an infection and returns to baseline.

Measles

Disease caused by Paramyxovirus, characterized by clinical signs such as Koplik's spots and a cephalocaudal rash spreading from the head to lower extremities.

Koplik's Spots

The hallmark sign of measles appearing $1-2\,\text{days}$ before the rash.

Mumps

Viral illness caused by a paramyxovirus affecting saliva-producing glands, primarily the parotid glands.

Common Cold

A self-limited viral upper respiratory infection, most commonly caused by Rhinovirus.

Rabies

Viral infection caused by Rhabdovirus, typically transmitted by the bite of a rabid animal and traveling through peripheral nerves toward the CNS.

Hydrophobia

A symptom of furious rabies involving difficulty swallowing and panic or spasms when presented with liquids.

Rubella

Disease caused by Rubella virus, characterized by post-auricular lymphadenopathy and Forchheimer's spots; known for teratogenic effects during the first $3\,\text{months}$ of pregnancy.

Forchheimer's Spots

A pinkish rash on the soft palate associated with rubella.

Congenital Rubella Syndrome

A condition resulting from fetal rubella infection associated with "blueberry muffin" skin, cardiac malformations, and microcephaly.

Viral Encephalitis

An acute inflammatory infection of the brain, frequently caused by Herpes simplex virus in developed countries.

Japanese Encephalitis Vector

The mosquito species Culex tritaeniorhynchus.

Influenza

Acute viral illness with an incubation period of $24-48\,\text{hours}$ ($1-4\,\text{days}$), often complicated by mixed viral and bacterial pneumonia.

Poliomyelitis

Disease primarily transmitted through the fecal-oral route that affects motor neurons of the brainstem and spinal cord.

Chickenpox

Infection caused by Varicella-zoster virus featuring a centrifugal distribution of itchy vesicles that evolve from macules to crusts.

Ebola Disease

Viral infection with an incubation period of $2-21\,\text{days}$, transmitted via contact with blood or body fluids and progressing from a "dry" phase to a "wet" phase.

COVID-19

Infection caused by the SARS-CoV-2 virus, typically detected via real-time RT-PCR or antigen tests.

Hepatitis B Transmission

Transmission through parenteral exposure, intimate or sexual contact, and perinatal routes.

Hepatitis D

A virus that is dependent on Hepatitis B surface antigen for replication.

Dengue Hemorrhagic Fever

Manifestation of dengue including petechiae, purpura, epistaxis, thrombocytopenia, and hemoconcentration.

Syphilis

A sexually transmitted infection characterized by a painless chancre in its primary stage.