Environmental Engineering Reference
In-Depth Information
infections. Pandemics of influenza occurred in 1889, 1918, 1957, and 1968.
During these pandemics, 20 percent of the general population and 50 percent
of institutionalized populations (prison, college dormitories) were affected.
1
Although seasonal influenza deaths occur in the elderly, during the 1918
pandemic, most deaths were in young adults, for reasons that are unclear. Birds
can be infected with influenza, and the pandemic strains from 1918, 1957 and
1968 bore genetic similarity to avian influenza viruses. This observation drives
much of the fear and speculation about avian influenza and the likelihood of it
morphing into the next human pandemic.
The specter of an influenza pandemic highlights many shortcomings in global
health care. It is likely that the pandemic will begin in a developing country
where there is close human and bird contact and veterinary surveillance is low,
most likely on a farm or a food processing facility. Crowded living conditions
will exacerbate the spread, and international air travel will move the virus to
new regions of the world overnight. At that point, much will depend on the
international cooperation in response to the perceived threat. If active control
measures are put into place, there is the potential to reduce the severity, but most
of the medical literature is imbued with a sense of inevitability. Whether the
pessimism is warranted will be revealed with actual experience.
The availability of medical tools (respirators, vaccines, antivirals) has been
the concern of much of pandemic influenza planning. Treating severe influenza
is medical-resource intensive; respirators for those with impaired lung capacity
are already in short supply, and must be regularly cleaned and patients monitored.
Spread of influenza in health care facilities is likely, with the potential to infect
health care staff. The potential volume of patients will overwhelm most hospitals,
but other disruptions will occur due to absenteeism among employees needed to
keep society functioning.
Airborne, or fine-droplet transmission, may also occur. In view of this, Standard
Infection Control Principles and Droplet Precautions are the principal infection
control strategies that should be rigorously followed. In certain circumstances,
these control measures may need to be augmented with higher levels of respiratory
protection. Scrupulous attention to handwashing and containment of respiratory
secretions produced by coughing and sneezing are the cornerstones of effective
infection control. Other key recommendations include separation or cohorting of
patients with pandemic influenza from those who have other medical conditions;
prompt identification of health care workers with pandemic influenza; restric-
tion of ill workers and visitors from health care settings; and education of staff,
visitors, and patients about the transmission and prevention of influenza that is
understandable and applicable to their particular situation.
61
BIOTERRORISM
In late 2001, letters containing
Bacillus anthracis
(anthrax) spores were mailed to
various locations in the United States by yet unidentified individual(s) operating
under unknown motive(s). This led to the deaths of at least five individuals due
