Infectious disease -A disease caused by a microorganism that provokes an
immune response in the host, and that can be passed to
another host. Identified by Koch’s postulates.
Koch’s Postulates -The foundation of the germ theory of disease, used to
establish whether a disease is caused by a
microorganism. They are: The pathogen must be found
in all individuals with the disease; the organism must be
isolated and grown in pure culture; the culture should
cause the disease when introduced into another healthy
individual; the pathogen can be isolated from the
second individual and grown in a culture.
Pathogen -A microorganism that causes disease in a host.
Probiotic -Helpful microorganisms that colonize the
Parasites -Microorganisms that make use of the resources of
other individuals, usually of a different, larger bodied
Commensals -relationship between two organisms where one
organism benefits but the other is unaffected
Virulence -A pathogen’s ability to make a host sick; can be due to
high reproduction rate of the pathogen, its ability to
produce a toxin, or other attributes.
Vector -Any intermediate species/material that can take a
pathogen from on host to the next.
IgE -One of the classes of antibodies that respond to
helminth injections. IgE appears to be involved in
allergies and asthma
Immune Response -The reaction of the cells and fluids of the body to the
presence of a substance that is not recognized as a
constituent of the body itself
Innate Immune System -An evolutionarily old part of the immune system that
involves recognition of some common patterns rather
than specific characteristics of pathogens.
-Fast, no memory, phagocytes, broad recognition
Adaptive Immune System -A part of the immune system found only in vertebrates.
It involves recognition of specific pathogen
-Slow, memory, lymphocytes, high specificity
Lymphocytes (B- and T-) White blood cells, which are key cells of the immune
-B – effective against extracellular infection
-T – effective against intracellular infection
Allergen -Antigens that are not pathogenic
Allergies -An immune response to antigens that are not, in and of
themselves, deleterious. Characterized by the release of IgE and inflammation of epithelial cells of the skin,
respiratory, and gastrointestinal tracks.
Asthma -Constriction, inflammation, or both, of the bronchia of
the lungs, usually resulting from an allergic reaction
Hygiene Hypothesis -A hypothesis developed to explain the rise in allergies
in industrialized countries. Suggests that improvements
in hygiene have resulted in less exposure to pathogens
in childhood, which alters the development of the
immune system in ways that cause it to respond
inappropriately to non-pathogenic antigens.
Helminth Hypothesis -A hypothesis developed to explain the link between
IgE and allergy. Suggests that reduced exposure to
helminths results in IgE responding to non-pathogenic
antigens with properties similar to those of helminths.
Emerging infectious disease -Diseases of infectious origin whose incidence in
humans has increased within the past two decades or
threatens to increase in the near future.
Resurging infectious disease -Infectious diseases whose prevalence had declined, but
is now increased or likely to increase.
Epidemiological transition -The process whereby major communicable diseases
and conditions of poverty (e.g. malnutrition) are
progressively replaced by non-communicable diseases
such as cancers and CVD
Antibiotic resistance -When bacterial species are not negatively affected by
Stressor -Challenges to health and well-being, survival and
reproduction, or anything that generates a physiological
Stress response -The way that your physiology is altered when you are
exposed to or imagine a stressor.
Theory of mind -An analytical construct to describe how animals and
humans interpret the mental state and intentionality of
others within the species.
Autoimmune disease -Diseases in which the immune system attacks the
body’s own cells, as if mistaking them for non-self
Income disparity -Inequality of income
Lifestyle incongruity -Inconsistency between one’s lifestyle and one’s
education/occupation, such that the status that goes
along with a particular lifestyle is higher than what