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Epi Wit & Wisdom Articles
Epidemiologists Contributing
Their Special Brand of Expertise in Rwanda-Zaire
Data Make a Difference
Epidemiologists in the war-torn
areas of Rwanda and Zaire are playing a major role in helping
clinicians and policy makers by providing data used to make decisions.
“You need to have numbers to
have a reasonable grasp of the situation, and that accounts for any
success epidemiologists have had in making themselves useful,” says
David Robinson, program manager of the Acute Respiratory Infections
group at WHO and head of the WHO team of epidemiologists working in
Goma, Zaire on the international relief effort to help Rwandan
refugees. Almost two dozen epidemiologists from the WHO, from
non-governmental organizations such as the French-based EpiCentre, and
from the Centers for Disease Control and Prevention (CDC) working
under the auspices of UN agencies (UNHCR and UNICEF) have been in
central Africa this summer.
But exactly what did
epidemiologists do in Africa and of what value was it? Robinson
pointed to several types of surveillance activities, each of which
served a separate purpose.
First, epidemiologists have been
collecting surveillance data on the numbers and causes of deaths and
on the cases of diarrhea. By differentiating between cases of watery
and bloody diarrhea in reporting, i.e., between cholera and dysentery,
epidemiologists also helped pinpoint the need for antibiotics to treat
dysentery. Detection of drug-resistant strains of shigella helped
policy makers decide on the need for the more effective—albeit the
more expensive—drug.
Epidemiologists Provide Reality
Check
The work of epidemiologists
which clarified the epidemiology of bloody diarrhea over the past two
years in neighboring countries helped to avoid protracted debates
about drug policy,” says Mike Toole, an epidemiologist and CDC’s
technical coordinator for Complex Emergencies. When data showed that
watery diarrhea was decreasing and bloody diarrhea increasing, an
immediate response was called for. Clinicians were “screaming for
guidance,” and surveillance data plus earlier work helped
policy-makers get through a tough decision, says Toole.
Second, epidemiologists have
been helpful in defusing rumors and panic about other diseases,
according to Robinson. For example, meningitis cases were reported
early on. With assistance of the laboratory, epidemiologists were able
to show that this was not a first priority problem. Again,
policy-makers benefited from the work done earlier by epidemiologists
showing that epidemics were unlikely to break out below a certain
threshold number of cases, says Toole. Epidemiologists were able to
track the occurrence of the disease and keep it under surveillance, a
critical function which provided much needed reassurance. When cases
surpassed the threshold in one camp, vaccinations were started, but
not before. This information was extremely useful to donors trying to
make decisions about vaccine purchases and vaccination campaigns.
Thirdly, epidemiologists have
been helpful by listening closely to clinicians and spotting potential
new problems early on. Clinicians turned up a series of cases with
high fever, severe conjunctivitis, and some neurologic excitability
and were convinced they were dealing with typhus. If typhus had been
accepted as the diagnosis, this would have had enormous implications
for the refugee population of 850,000 living in the camps, Toole
pointed out. Early tests have been negative, and while the etiology is
still unknown, typhus has been ruled out. De-lousing actions have been
taken, though, since cases seem to occur primarily in lice covered
persons.
Sessions Provide Info Exchange
Another important function of
the surveillance data is their usefulness in determining whether or
not progress is being made in reducing the death rate. This is the
goal on which all participant donors agree, and front line workers now
accept the need to make an extra effort to collect this information in
the middle of all the other overwhelming tasks they must perform in
these crisis situations.
One unexpected benefit which
evolved from epidemiologic data was its motivating power to get people
to work together, Toole continued. Donors working in Rwanda between
April and July when massacres occurred were distressed and isolated.
Largely through the hard work of
Les Roberts, an epidemiologist working out of nearby Uganda, a weekly
meeting was held to share standardized information and feedback about
the situation. This “epidemiologic information exchange” became the
centerpiece of a coordinating mechanism among the donors, according to
Toole. It was a useful forum to provide data on a meningitis outbreak
and to explain to donors why vaccine efficacy can still be high even
when the number of cases which are vaccinated is high (the number is
partly a function of the vaccination coverage not just the efficacy).
Another unanticipated use of
epidemiology occurred when an epidemiologist was asked to make sense
of the medical supply situation. According to Toole, planeloads of
drugs and supplies were arriving with little evidence to support their
need. Working “off center stage,” Brent Burkholter, an epidemiologist,
began using surveillance data to predict the type and quantities of
supplies needed. He turned the situation around completely and based
predicted needs on the morbidity profile, says Toole, impressed by
this achievement.
Published October 1994 v
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