-
The human body provides a habitat for other, much smaller
organisms, some of which
make us sick.
-
The human body
mounts a defense against pathogens.
-
The effort to manage infectious disease risk incorporates
several different approaches.
-
When people are close to one another, pathogens can be
transmitted from one person
to another simply through proximity; this is transmission through
closeness or contact.
-
Airborne transmission of pathogens is distinct from
transmission via respiratory droplets
in the air.
-
Fecal–oral pathways for the transmission of infectious
disease are important in
public health.
-
Foodborne illness
emerges as a distinct phenomenon only where there is clean tap water.
-
The keys to food
safety in the kitchen are (1) preventing contamination by pathogens as
much as possible and (2) managing time and temperature to minimize the
growth of populations of pathogens when prevention fails.
-
The term vectorborne
disease refers specifically to diseases transmitted by a biological
vector.
-
Infectious disease is
an important cause of mortality and morbidity on a global scale.
-
In the United States,
responsibilities related to infectious disease are divided between state
governments and the federal government.
-
Certain plants,
animals, and fungi produce poisons that are acutely toxic to humans.
Most of these cause relatively isolated incidents of poisoning in
individuals or local groups. In contrast, exposures to aflatoxin create
a substantial public health burden.
-
Allergy and asthma,
which are conditions of the immune system, have been linked to some
environmental factors.
-
Mortality from
natural disasters is highly variable over time, but certain types of
disasters tend to cause very high mortality when they occur.
-
Some isotopes of
certain chemical elements are radioactive: an unstable isotope ejects
part of its nucleus, thus emitting radiation and “decaying” into a
different element.
-
Radioactive decays
occur in characteristic series; each isotope in the chain has a
characteristic half-life, and each decay emits a characteristic type of
radiation.
-
In public
health, we make a key distinction between radiation that has enough
energy to create charged ions in the body and radiation that does not
have enough energy to do this.
-
From a public health
standpoint, alpha, beta, and gamma radiation pose distinct hazards in
terms of the intensity of their damage to tissue and in terms of the
shielding required to protect against them. These two issues are
related.
-
Ionizing radiation’s
biological effects are relatively well established and depend on the
level of exposure.
-
People are routinely
exposed to naturally occurring radiation, both ionizing and nonionizing.
-
Naturally
occurring radiation, both ionizing and nonionizing, has impacts on human
health.
