Global Health, Infectious Diseases, and Maternal-Child Wellness

Comprehensive vocabulary flashcards covering the chain of infection, major global infectious diseases (tuberculosis, HIV/AIDS, malaria), maternal and neonatal health transitions, nutritional metrics, cardiovascular epidemiology, and behavior models.

Agent

A pathogen (virus, bacterium, fungus, or parasite), chemical, or physical cause of disease or injury.

Host

A human who is susceptible to infection or another type of disease or injury.

Environment

External factors that facilitate or inhibit health, including physical, built, and social and political environments.

Pathogen

An biological agent able to cause or produce disease.

Vector

An organism (usually a nonvertebrate) that transmits a pathogen to another organism.

The Chain of Infection

A model illustrating the transmission of an infectious condition through six connected components: infectious organism, reservoir, portal of exit, mode of transmission, portal of entry, and vulnerable host.

Reservoir

The place where an infectious microorganism lives and thrives.

Portal of Exit

The route or mechanism through which an infectious microorganism leaves its reservoir.

Mode of Transmission

The method by which an infectious microorganism transmits from one person or place to another.

Portal of Entry

The site or pathway through which an infectious microorganism gets into the host.

Vulnerable Host

A person most at risk of infection due to lacking the ability to fight infection.

Incubation Period

The time period extending from the transmission of the pathogen until the onset of symptomatic disease.

Latent Period

The interval of time from the initial transmission of the pathogen to the start of the period of communicability.

Period of Communicability

The period during which an infected host can transmit the pathogen to another susceptible individual, which can occur during both asymptomatic and symptomatic phases.

The Big Three in Infectious Disease

HIV/AIDS, tuberculosis, and malaria; the three major infectious conditions that have received the bulk of global health attention and financing in recent decades.

Tuberculosis

A disease caused by infection with Mycobacterium tuberculosis bacteria that spreads via airborne droplets and was historically referred to as consumption.

Latent TB

A stage of tuberculosis infection where the bacteria live but do not grow in the body, remaining asymptomatic and incapable of spreading from person to person.

TB Disease

An active tuberculosis infection where bacteria grow in the body, cause clinical symptoms (such as coughing up blood, chest pain, weight loss, and fevers), spread to others, and can cause death if left untreated.

Bacillus Calmette-Guérin (BCG) Vaccine

A vaccine that is not effective at preventing primary TB infection, but is used to reduce the risk of severe active TB disease and related complications in children.

DR-TB

Drug-resistant tuberculosis, representing a growing global health challenge where the bacteria do not respond to standard antimicrobial drugs.

MDR-TB

Multidrug-resistant tuberculosis that does not respond to at least two of the standard first-line antibiotic therapies.

XDR-TB

Extensively drug-resistant tuberculosis that fails to respond to at least three antibiotics as well as at least one second-line injectable medication.

Directly Observed Therapy (DOT)

A treatment adherence strategy where a healthcare provider observes the patient swallowing each dose of TB medication.

Human Immunodeficiency Virus (HIV)

A retrovirus that infects and destroys specialized immune cells needed by the body to fight off infection.

Acquired Immunodeficiency Syndrome (AIDS)

The advanced disease state resulting from the destruction of key immune system cells by HIV.

Opportunistic Infections

Secondary infections that develop when the host's immune system is already compromised, such as during advanced HIV infection.

Antiretroviral Therapy (ART)

A combination regimen of medications taken as pills or injections that suppresses HIV replication and lowers viral loads to help patients live long, healthy lives without curing the infection.

PrEP vs. PEP

Pre-exposure prophylaxis (medications taken before potential exposure to prevent HIV) compared with post-exposure prophylaxis (medications taken promptly after potential exposure to prevent infection).

U=U

A public health principle meaning 'Undetectable = Untransmittable', indicating that individuals on effective ART with an undetectable viral load cannot sexually transmit HIV to others.

Vertical Transmission

Mother-to-child transmission of an infectious pathogen occurring from an infected pregnant woman to her offspring during pregnancy, childbirth, or breastfeeding.

Enteric Infection

An infectious disease process occurring within the intestinal tract.

Gastroenteritis

Infection-induced inflammation of the inner lining of the stomach and/or intestines characterized by nausea, diarrhea, vomiting, and fever.

Diarrhea

The passage of loose or liquid feces with increased frequency of defecation, which can precipitate severe dehydration, kidney failure, heart failure, and death.

Oral Rehydration Therapy (ORT)

A tertiary treatment for severe diarrhea that uses oral rehydration salts (ORS) dissolved in clean water to prevent and treat life-threatening dehydration.

5 Fs of Fecal-Oral Transmission

The five principal pathways for transmitting gastrointestinal pathogens: fluids, fingers, flies, food, and fomites.

Acute Health Condition

A medical condition characterized by rapid onset that typically resolves within a few days or weeks.

Chronic Health Condition

A health disorder that develops slowly and may persist or progressively worsen over months or years.

Upper Respiratory Infection (URI)

An acute infection localized to structures including the nose, sinuses, pharynx, larynx, or trachea.

Lower Respiratory Infection (LRI)

An acute infection affecting the bronchi, bronchioles, air sacs, or pulmonary lung tissue.

Vaccination

The intentional delivery of a substance into the body to stimulate the development of immunity against a specific pathogen.

Immunization

The physiological process by which an individual's immune system builds protective immunity against an infection after receiving a vaccine.

Antibody

A protective protein produced by the human immune system in response to antigens.

Active Immunity

Protection against infectious diseases generated when an individual's own immune system produces antibodies against a specific pathogen.

Passive Immunity

Temporary protection against an infectious pathogen provided by transferring antibodies produced by another human or animal host.

Epidemic

An infectious disease that spreads rapidly within a finite geographical area.

Pandemic

An infectious disease outbreak that spreads rapidly across several countries, continents, or worldwide.

Endemic

An infectious condition that is continuously and stably present at a baseline level in a specific population or region.

Intermediate Host

A host in which an immature parasite develops and may replicate asexually, but does not achieve sexual maturity.

Definitive Host

A host in which a parasite attains sexual maturity and reproduces sexually.

Malaria Parasite Life Cycle

A dual-host cycle wherein sexual reproduction occurs within the mosquito vector (gametes to zygote, ookinete, oocyst, and sporozoites) and asexual reproduction takes place within the human host (liver cells and red blood cells).

Neglected Tropical Diseases (NTDs)

Infectious diseases primarily concentrated in the world's poorest regions that historically have lacked adequate research, funding, and pharmaceutical development.

Arbovirus

An arthropod-borne virus transmitted to vertebrate hosts by arthropods such as mosquitoes or ticks (including Dengue, Chikungunya, Yellow fever, and Zika).

Emerging Infectious Diseases

Infections caused by pathogens that have not previously caused severe disease in humans, or known agents that are expanding into new host ranges or populations.

Zoonotic Diseases

Diseases originating from animal pathogens that mutate to cross the species barrier, allowing transmission to humans to cause illness.

Continuum of Disease Eradication

The progressive public health framework scaling from local Control to country-level Elimination (validation), regional Elimination of transmission (verification), global Eradication (certification), and final Extinction.

Transmissibility

The ease with which an infectious agent moves from one host to another.

Infectivity

The capacity of an infectious agent to establish an infection in a susceptible host.

Pathogenicity

The capacity of an infectious agent to induce clinical illness or symptoms in an infected host.

Virulence

The ability of an infectious agent to cause severe morbidity or death, often reflected by high case fatality rates.

Total Fertility Rate (TFR)

The average number of children a woman gives birth to during her reproductive childbearing years.

The Fertility Transition

A demographic transition characterized by a shift from high birth rates to a reduced number of children born per woman following socioeconomic advancement.

Replacement Population

A demographic replacement level where each woman bears an average of two children—one to replace herself and one to replace her partner.

Gravidity

The total cumulative number of times a woman has been pregnant, including miscarriages, abortions, stillbirths, and live births.

Fertility

The total number of births experienced by a woman, counting both live births and stillbirths.

Parity

The total number of live births delivered by a woman.

Contraception

The intentional prevention of conception or pregnancy using modern barriers, medications, or surgical methods.

Period Poverty

The inability of women and girls to afford menstrual management supplies or access suitable water and sanitation infrastructure, resulting in health, social, and economic burdens.

Antenatal Care

Routine, preventative healthcare visits attended during pregnancy to monitor maternal and fetal health.

Miscarriage

The spontaneous loss of a pregnancy between $0\text{ and }22\text{ weeks}$ of gestation.

Stillbirth

Fetal demise occurring after $22\text{ weeks}$ of gestation (or $28\text{ weeks}$ under international comparison definitions), subdivided into antepartum (before labor) and intrapartum (after onset of labor).

Early Neonatal Death

The death of a live-born infant occurring within the first $0\text{ to }7\text{ days}$ after birth.

Late Neonatal Death

The death of a live-born infant occurring between $7\text{ and }28\text{ days}$ after delivery.

Hyperemesis Gravidarum

A pregnancy disorder characterized by relentless nausea and vomiting, leading to severe maternal dehydration and weight loss.

Ectopic Pregnancy

A dangerous complication wherein a fertilized ovum implants outside of the uterine cavity.

Placenta Previa

An obstetric complication where the placenta implants low in the uterus, partially or completely covering the cervical os and predisposing to bleeding.

Placental Abruption

The premature detachment of the placenta from the uterine wall before the delivery of the baby.

Preeclampsia

A serious gestational syndrome marked by new-onset worsening hypertension accompanied by proteinuria.

Obstructed Labor

A condition during delivery where the unborn baby becomes mechanically wedged in the birth canal, causing maternal soft tissue ischemia and necrosis.

Postpartum Hemorrhage

Severe, life-threatening blood loss occurring after the delivery of a newborn.

Maternal Mortality Rate

The number of maternal deaths resulting from pregnancy-related causes during pregnancy, childbirth, or within six weeks of delivery, expressed per $100{,}000$ live births.

Neonatal Mortality Rate

The number of infant deaths occurring within the first $28\text{ days}$ after birth per $1{,}000$ live births.

Infant Mortality Rate

The number of deaths of infants before their first birthday per $1{,}000$ live births.

Obstetric Transition

A population health pattern characterized by a shift from high maternal mortality to very low maternal mortality alongside socioeconomic development.

Birth Asphyxia

A neonatal complication occurring when an infant fails to establish spontaneous breathing immediately after birth and experiences severe oxygen deprivation.

Emergency Obstetric and Newborn Care (EmONC)

A critical package of seven life-saving signal functions designed to treat acute obstetric and newborn complications during the perinatal period ($22\text{ weeks}$ gestation to $7\text{ days}$ postpartum).

Skilled Birth Attendant (SBA)

A licensed health professional (such as a doctor, midwife, or nurse) proficient in managing labor, delivery, and postpartum complications in mothers and neonates.

Traditional Birth Attendant (TBA)

A community birth assistant whose training is acquired through informal apprenticeship rather than accredited medical curricula, lacking qualifications to treat medical emergencies.

Malnutrition and Infections Cycle

A reciprocal negative feedback loop where undernutrition suppresses immune defenses causing infection, and infections subsequently deplete nutrient reserves to exacerbate malnutrition.

Nutrition Transition

A societal dietary shift from prevailing undernutrition and micronutrient deficiencies to overweight and obesity as dominant public health concerns.

Anthropometry

The standardized quantitative physical measurement of the human body's proportions, size, and composition.

Wasting

A marker of acute undernutrition in children characterized by low weight-for-height, indicating rapid nutritional deterioration.

Stunting

A presentation of chronic undernutrition indicated by low height-for-age, reflecting long-term nutritional and developmental deficits.

Moderate Acute Malnutrition (MAM)

A nutritional state defined by a weight-for-height z-score between $-2$ and $-3$ or a mid-upper arm circumference (MUAC) between $11.5\text{ cm}$ and $12.4\text{ cm}$.

Severe Acute Malnutrition (SAM)

A critical state of acute undernutrition defined by a weight-for-height z-score below $-3$ or a mid-upper arm circumference (MUAC) of less than $11.5\text{ cm}$.

Food Security

Reliable physical, social, and economic access for all household or community members to sufficient, safe, and nutritious food to sustain an active and healthy life throughout the entire year.

Food Desert

A geographic area (urban or rural) where access to affordable, fresh, and nutritious whole food is severely limited.

Epidemiologic Transition

A public health shift wherein infectious illnesses are supplanted by noncommunicable, chronic conditions as the primary causes of disability and mortality in a population.

Cardiovascular Disease (CVD)

A class of noncommunicable disorders involving the heart or systemic blood vessels, responsible for approximately one-third of all global deaths.

Ischemic Heart Disease (IHD)

Coronary artery narrowing caused by atherosclerotic plaque accumulation that diminishes blood supply to the myocardium, accounting for $49\%$ of all CVD deaths.

Angioplasty

A minimally invasive mechanical procedure to physically unblock and dilate narrowed or occluded coronary arteries.