Environmental Engineering Reference
In-Depth Information
research, and sets regulations for environmental exposures. Military involvement
in outbreaks of infectious diseases with large-scale implications has increased
over the last decade, due in part to increased fears of bioterrorism. Specialized
offices for particular diseases also exist, such as for mental health and substance
use and pandemic influenza. Public and private health financing agencies also
have a strong interest in health promotion and may also be involved in interven-
tions. Many infectious diseases have animal sources and veterinary regulatory
agencies may also be involved in quelling an outbreak.
Also at the national level are commercial managed health care insurance orga-
nizations and public health financing authorities, such as Medicaid, Medicare and
the Veterans' Administration (VA) system. These organizations exert influences
on the types of diseases that are treated and what medications can be used. For
example, a health plan may or may not reimburse for preventative malarial pro-
phylaxis or particular vaccines. Insurance plans also dictate which antibiotics will
be paid for, and the order in which they can be used in complicated cases. The
medical records from these organizations can be a rich source of data for deter-
mining the incidence of infectious diseases that require medical attention, as well
as afford details of the comorbid conditions that exist in those presenting with
infectious diseases. These organizations also conduct regular review of causes of
illness and can make convenient partners in disease investigations.
At the international level, the World Health Organization (WHO) is a technical
organization that issues best-practice guidelines and assists member nations in
disease prevention and eradication projects. The interactions between these levels
of health organizations and regulators become of importance when multidimen-
sional health interventions are proposed. Jurisdictional constraints may limit the
reach a health promotion program has and will dictate which parties are involved.
EPIDEMIC CONTROL AT THE INDIVIDUAL LEVEL
Control of infections at the individual level is achieved primarily through three
different measures: behavior modification, treatment with antibiotics and antivi-
rals, and prevention through vaccination. We will describe these interventions
at these three levels, followed by descriptions of environmental and infectious
agent control. First, some basic terminology will be elaborated.
An infected individual goes through four basic stages: incubation period, car-
rier state, fulminate infection, and remission/immunity. The incubation period is
the interval between exposure of a susceptible host to an agent and the establish-
ment of the infection in the host. There are usually no clinical signs of disease in
the host during this period. During this period, the person is not usually infectious
to others. In the carrier state, the person or animal that harbors an infectious agent
in the absence of discernible clinical disease and serves as a potential source of
infection; this happens after the incubation period. The carrier state may exist
in an individual with an infection that is outwardly unapparent throughout its
course. The carrier state may be of short or long duration. During the third stage,
