Download DISEASE SURVEILLANCE An essential component of public health Burton Wilcke Zeigler Forum

DISEASE SURVEILLANCE
An essential component of public health
Burton Wilcke
Zeigler Forum
April 30, 2015
What will we be covering?
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Principles of disease surveillance
History of disease surveillance
Three surveillance scenarios
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Botulism
Salmonellosis
Ebola Hemorrhagic Fever
“Tell me and I forget, teach me and I
may remember, involve me and I
learn.”
Benjamin Franklin
Definition
Health surveillance“The ongoing systematic collection,
analysis, and interpretation of
outcome-specific data for use in the
planning, implementation, and
evaluation of public health practice.”
Thacker and Berkelman, 1988
Health Surveillance
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Estimates the magnitude of the problem
Determines the geographic distribution
Establishes the natural history of disease
Detects epidemics
Evaluates control measures
Monitors changes in infectious agents
Detects changes in practice
Facilitates planning
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Key Surveillance Concepts
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Morbidity vs. Mortality
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Prevalence vs. Incidence
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Sensitivity vs. Specificity
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Confidentiality vs. Privileged
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Case definition
Evolution of Health Surveillance (US)
1850-Massachusetts Sanitary Commission
Related morbidity/mortality rates to
“living conditions”
1850-US Census
Included death registration
1874-Massachusetts State Board of Health
Voluntary disease reporting
Evolution of Health Surveillance (US)
(cont’d)
1893-Michigan required disease reporting
1925-National disease reporting
1946-CDC formed
1952-MMWR published
Surveillance Issues
Quality of data
► Completeness
► Definitions/classification
► Timeliness
► Checks on redundancy
► Contact tracing
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Surveillance Systems
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Infectious disease reporting
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HCPs
Laboratories
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Disease registries
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Risk factor surveys
Botulism
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Sx: Ptosis, diplopia, blurred vision,
dysphagia, dysarthria, constipation
Hx: Ingestion of poorly-preserved
or inadequately processed foods
that are low in salt, sugar, or acid
Botulism
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Cause: Ingestion of a heat-labile
toxin that is produced by
Clostridium botulinum. This is the
most potent biological toxin known
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Dx: Detection of toxin in serum
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Tx: Antitoxin and supportive care
Infant Botulism
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Sx: “Failure to thrive,” poor suck,
altered cry, loss of head control,
“floppy baby syndrome,”
constipation
Hx: No history of ingestion of
poorly-preserved or inadequately
processed foods that are low in salt,
sugar, or acid
Infant Botulism
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Dx: Detection of toxin in serum:
negative,
however
detection of toxin in stool: positive.
Detection of C. botulinum in stool
Tx: Antitoxin and supportive care
Infant Botulism: The culprit
Infant Botulism: The vehicle
Salmonellosis
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Sx: Diarrhea, abdominal pain,
fever, nausea
Hx: Ingestion of raw or
undercooked food, viz. eggs, milk,
poultry, meat, other foods
Salmonellosis
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Cause: Ingestion of sufficiently
large enough infectious dose of
Salmonella enterica.
Risk correlated to dose and immune
status.
Dx: Isolation of S. enterica
Tx: Rehydration and electrolyte
replacement, conditionally
antibiotics
Salmonellosis
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Epidemiologic and laboratory followup: Food history. Testing of suspect
foods.
Findings: Implicated food was
boiled eggs on the salad bar
Salmonellosis: Association with raw eggs
Salmonellosis: Foodborne
Ebola Hemorrhagic Fever
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Sx: Fever, malaise, myalgia,
headache, frequently also with
pharyngitis, vomiting, diarrhea,
rash
Hx: Exposure to blood or organs of
infected primates (bush meat)
Ebola Hemorrhagic Fever
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Cause: Introduction of the Ebola
virus via mucous membranes or
ingestion. No evidence of aerosol
transmission.
Dx: Detection of virus or viral
antigen in blood. Evidence of
antibody response to Ebola virus
Tx: No antiviral treatment available
Ebola Hemorrhagic Fever
Ebola Hemorrhagic Fever
Ebola Hemorrhagic Fever
Ebola Hemorrhagic Fever
Disease Surveillance
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Basic epidemiologic capacity is
needed in every country
Basic laboratory capacity is needed
in every country
Disease Surveillance
Basic communicable disease
surveillance should be as much a part
of public health infrastructure as the
right to primary healthcare.
This position was adopted by the
World Health Assembly in 2005.
To date, this goal has not been
achieved.