CHOLERA
OTHER DISEASES
AND
SW3
What
What Is It?
BENCHMARK
Cholera is a serious water-borne disease caused by
Maintain current conditions of no
Maintain
the bacterium Vibrio cholerae, which thrives in polluted
cholera cases over the next 5 years.
waterways. Localized outbreaks are often associated
Identify and assess risk to other
with water pollution and unsanitary conditions caused
diseases linked to environmental
by human activities, particularly improper treatment of
health.
health.
human sewage. In some areas, scientists have found
a significant correlation between cholera incidence
TA R G E T
and elevated sea surface temperature (SST)7.
Remain cholera-free over the next 10
Remain
Other diseases associated with habitat destruction,
years. Reduce human exposure to
destabilization of natural wildlife populations and
diseases by improving environmental
global climate change may become an increasing
conditions.
problem in the MAR region. Emerging diseases of
concern include hantavirus pulmonary syndrome,
RED FL AG
Lyme disease and avian flu. This indicator will be further
developed as more data are collected concerning
Any reported cases of cholera or
these emerging diseases and their relationship to
outbreaks of other environmentally
environmental health.
linked diseases.
linked
Why
Why Do We Measure It?
Cholera outbreaks among coastal communities can
Usefulness
be used as an indicator of the overall health of the
population and their general living conditions. Due to
Tracking the prevalence of cholera and other diseases
the correlation between the cleanliness of waterways
that are linked to environmental health is an important
and the occurrence of cholera, cholera outbreaks
measure of ecosystem health for the MAR. Cholera
can be used as an indicator of water quality and
cases and outbreaks are generally indicative of poor
sanitation. Cholera can also be transmitted through
sanitary and water quality conditions that contribute
uncooked fish or shellfish in which Vibrio cholerae
to reef degradation. It is assumed that the more
have accumulated. Cholera outbreaks also occur
numerous or frequent the outbreaks, the poorer
when ocean surface temperatures increase. The
the water quality and the less sanitary the living
bacteria, V. cholerae, live in marine ecosystems by
conditions--and the more likely reef quality is to be
attaching to zooplankton. Zooplankton depend on
poor.
eating phytoplankton, and when ocean temperatures
increase, phytoplankton bloom, allowing for both
Status
Status
zooplankton and V. cholerae to increase.
With the exception of Belize, all countries in the MAR
How Do We Measure It?
region experienced significant cholera outbreaks in
the 1990s. Nevertheless, by 2004 the Pan American
This indicator is expressed in terms of the number
Health Organization (PAHO) declared Central America
of confirmed cases of cholera recorded in coastal
to be cholera-free. Belize reported its last case of
communities annually and in recent history (past 5
cholera in 1999; Honduras and Mexico, in 2001; and
10 years). It can also be expressed as the prevalence
Guatemala, in March 2002. According to PAHO, the
rate (per 1000 people) to account for the different
lone Guatemalan case in 2002 was the last recorded
sizes of coastal populations. A disease outbreak can
case of cholera in the Central American isthmus.
be recognized by a rapidly growing incidence rate (i.e.,
Note that these data are reported as number of
number of new cases within a given time frame) within
cases, rather than as a prevalence rate or number of
a specific geographic location.
outbreaks 8.
128