Environmental Engineering Reference
In-Depth Information
prohibitions save thousands of lives each year.
19
Condom use and the availability
of sterile syringes have been shown to reduce the incidence of HIV, hepatitis,
and other sexually transmitted and injection-borne infections.
20
In order to reduce
West Nile virus infection from mosquito bites, the use of personal insect repellent
and staying indoors at dusk (when the disease carrying insects were active) is
encouraged in epidemic areas.
21
Hand washing by foodservice staff also prevents
transmission of foodborne diseases, as do industrial hygiene standards for food
processing and inspections of facilities.
22
Protective masks are recommended
for tuberculosis patients, and gain widespread public use during the outbreak of
severe acute respiratory syndrome (SARS).
23
The interventions described here involve the modification of human behaviors.
In order to affect such changes, broad population-based educational campaigns are
often used. Laws (such as for seatbelts) can also be enacted to require protective
measures be taken for prevention or mortality and morbidity. Fear of sanction,
as in the foodservice example, can also serve as a means for creating behavior
change. In general, behavioral changes require a willingness on the part of the
population to take protective measures to ensure the safety of themselves, but
also of others. These types of interventions may take considerable public attention
and concern to enact.
Antibiotics and Antivirals
Treatment of those who are showing symptoms of disease, and those who are
believed to have been exposed, benefit the individual, but can also shorten the
duration or severity of disease and thereby prevent infections in others.
The use of antibiotics and antivirals carry the risk of resistance developing
in the infectious agent that could render the drugs useless. When these medica-
tions are used indiscriminately, bacteria and viruses that carry naturally occurring
mutations that allow them to circumvent the mechanism of the drug's action will
have an evolutionary advantage and are likely to become the dominant strain.
Therefore, antibiotics and antivirals should be used judiciously and reserved for
cases in which they are most likely to confer a medical benefit.
Every drug carries a risk of unintended side effects. In epidemic control, mass
administration of antibiotics should be done carefully and limited to those who
are most likely to have been exposed. It is an ethically difficult decision to give
someone a medication when their level of exposure risk is unknown or low. In
such cases, the antibiotic or antiviral serves little or no individual benefit, while
the risks of their use to the individual remain. Therefore, mass administration of
these medications should be limited to very specialized situations.
Vaccination (or Immunization)
A vaccine is a suspension of attenuated live or killed microorganisms (bacteria,
viruses, or rickettsias), or purified protein or polysaccharide portions thereof,
administered to induce immunity and thereby prevent infectious disease. Vaccines
