Community and Public Health: Communicable and Noncommunicable Diseases

Vocabulary flashcards covering core epidemiological concepts, communicable disease transmission models, prevention levels, disease control strategies, and maternal and child health programs from the lecture transcript.

Infectivity

The ability of a biological agent to enter and grow in a host.

Pathogenicity

The capability of a communicable disease agent to cause or produce disease in a susceptible host.

Communicable Disease Model

A visual model depicting the minimal requirements for the occurrence and spread of communicable diseases in a population: agent, host, and environment.

Agent (Pathogenic Agent)

The cause of a disease or health problem; the element that must be present for a communicable disease to occur.

Host

Any susceptible organism—such as a single-celled organism, plant, animal, or human—that affords subsistence or lodgement to an infectious agent under natural conditions.

Environment (Communicable Disease Model)

All external physical, biological, or social factors that inhibit or promote disease transmission.

Chain of Infection

A conceptual model used to visualize the step-by-step process by which communicable diseases spread from an infected host or reservoir to a susceptible host in a community.

Case

A person who is sick with a disease.

Carrier

A person or animal that harbors a specific communicable agent in the absence of discernible clinical symptoms and is capable of serving as a source of infection.

Zoonosis

A communicable disease for which the reservoir resides in animal populations and can be transmitted to humans.

Anthroponosis

An infectious disease for which humans are the only known reservoir.

Direct Transmission

The immediate transfer of an infectious agent between infected and susceptible individuals through direct contact (such as touching, kissing, or intercourse) or direct droplet spray within a distance of one meter or less.

Indirect Transmission

Communicable disease transmission involving an intermediate step, which may be airborne, vehicleborne, or vectorborne.

Airborne Transmission

The dissemination of microbial aerosols—suspensions of dust or droplet nuclei containing microorganisms—to a suitable portal of entry, usually the respiratory tract.

Vehicle

An inanimate material or nonliving object (fomite)—such as toys, bedding, surgical instruments, food, water, or blood products—by which communicable agents are transferred to a susceptible host.

Vector

A living organism, usually an arthropod such as a mosquito, tick, louse, or flea, that can transmit a communicable disease agent to susceptible hosts.

Mechanical Transmission

Vector-borne transmission via contaminated mouthparts or feet of an insect where multiplication and developmental changes of the disease organism usually do not occur.

Biological Transmission

Vector-borne transmission involving multiplication and/or developmental changes of the disease agent inside the living vector before transmission occurs.

Etiology

The cause of a disease or health problem.

Multi-Causation Disease Model

A visual framework showing various internal factors (such as unique genetic endowment) and external physical, chemical, biological, and social environmental factors that promote or protect against complex noncommunicable diseases.

Active Immunity

Immunity that occurs when exposure to a disease-causing organism prompts the host's own immune system to develop antibodies against that disease via infection or vaccination.

Passive Immunity

Immunity that occurs when an individual receives antibodies against a disease rather than having their own immune system produce them, such as a newborn receiving maternal antibodies.

Isolation

The separation of infected persons or animals from susceptible individuals for the period of communicability to prevent direct or indirect transmission of an infectious agent.

Quarantine

The limitation of the freedom of movement of well persons or animals that have been exposed to a communicable disease and may be incubating it until the incubation period has passed.

Disinfection

The killing of communicable disease agents outside of the host, such as on countertops and physical surfaces.

Acquired Immunodeficiency Syndrome (AIDS)

The late stage of infection caused by the human immunodeficiency virus (HIV), characterized by the destruction of $CD4^+$ T cells and severe immune deficiency.

Pre-Exposure Prophylaxis (PrEP)

Daily preventative medications taken by individuals who test negative for HIV but are at high risk of acquiring the virus through sex or injection drug use.

Syringe Service Programs (SSPs)

Community programs that provide sterile needles and syringes, safe disposal of used injection equipment, overdose education and reversal with naloxone, and referrals to substance use treatment.

Bloodborne Pathogens

Disease-causing agents transmissible in blood and other body fluids, including HIV, hepatitis B virus ($HBV$), and hepatitis C virus ($HCV$).

Bloodborne Pathogens Standard

A regulatory set of safety rules promulgated by OSHA specifying employer and employee responsibilities regarding workplace precautions against bloodborne pathogens.

Categorical Programs

Health and welfare programs that are restricted only to individuals who qualify into a specific group based on variables such as disease, age, geography, or financial need.

Title V of the Social Security Act

Federal legislation enacted in 1935 dedicated specifically to promoting and improving the health, safety, and welfare of mothers and children in the United States.

Vaccines for Children (VFC) Program

A public health initiative created in response to the 1989 US measles outbreak to provide pediatric vaccines to participating clinics to ensure equitable vaccine access for all eligible children.