What’s New in Surveillance
Dona Schneider, PhD, MPH
 Surveillance is the ongoing, systematic
collection, analysis, and interpretation of
health data essential to the planning,
implementation, and evaluation of public
health practice, closely integrated with the
timely feedback of these data to those who
need to know.
Centers for Disease Control
Examples:
Morbidity and Mortality Weekly Report (MMWR)
Disease Registries
Surveillance for communicable
diseases remains important…
 The world population is highly
mobile
 International travel and troop
movements increase the risk of
communicable disease
transmission
 Migration for war and famine,
and voluntary immigration
increase communicable disease
risk
 Naturally occurring disease is
not our only threat
Types of Surveillance
 Passive
 Inexpensive, provider-initiated
 Good for monitoring large numbers of typical health events
 Under-reporting is a problem
 Active
 More expensive, Health Department-initiated
 Good for detecting small numbers of unusual health events
 Enhanced
 Rapid reporting and communication between surveillance
agencies and stakeholders
 Best for detecting outbreaks and potentially severe public
health problems
New and complex disease entities
must also be monitored…
 New syndromes may emerge
that present in an atypical
manner
 Syndromic surveillance uses
health-related data that
precede diagnosis and signal
a sufficient probability of a
case or an outbreak to
warrant further public health
response
Example of Passive Surveillance
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Day 1- feels fine
Day 2- headaches, fever - buys Tylenol
Day 3- develops cough - calls nurse hotline
Day 4- Sees private doctor – dx with “flu”
Day 5- Worsens - calls ambulance seen in ED
Day 6- Admitted - “pneumonia”
Day 7- Critically ill - ICU
Day 8- Expires - “respiratory failure”
Case enters surveillance system through an EDC
Example of Syndromic Surveillance
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Day 1- feels fine
Pharmaceutical
Day 2- headaches, fever
- buys TylenolSales
Day 3- develops cough - calls
nurse Hotline
hotline
Nurse’s
Day 4- Sees private doctor - dx “flu”
Managed Care Org
Absenteeism records
Day 5- Worsens - calls ambulance - seen in ED
Ambulance Dispatch (EMS)
Day 6- Admitted - “pneumonia”
Day 7- Critically ill - ICU
ED Logs
Day 8- Expires - “respiratory failure”
Case is under immediate investigation by the LHD
because of the pre-diagnostic information gathered
We also watch for sentinel events…
 Sentinel surveillance
identifies preventable
disease, disability, or deaths
that warn that known
methods of prevention,
treatment or safety need to
be improved
 Sentinel events may have
catastrophic outcomes – they
may indicate the “tip of the
iceberg”
Sentinel Surveillance
 Monitors
 Sites
 Events
 Providers
 Vectors/animals
SENTINEL EVENT
Nov 12, 2001 - 9:17 am
Flight AA 587 Crashes in Rockaways
7-Zip Surveillance showed:
27 Obs / 10 Exp Resp Emergencies
p<0.001
31 Obs / 16 Exp Hospital Events
p<0.05
10
/2
5
10 /20
/2 01
7
10 /20
/2 01
9
10 /20
/3 01
1/
2
11 00
/2 1
/2
11 00
/4 1
/2
11 00
/6 1
/2
11 00
/8 1
11 /20
/1 01
0
11 /20
/1 01
2
11 /20
/1 01
4
11 /20
/1 01
6
11 /20
/1 01
8
11 /20
/2 01
0
11 /20
/2 01
2
11 /20
/2 01
4
11 /20
/2 01
6
11 /20
/2 01
8
11 /20
/3 01
0/
2
12 00
/2 1
/2
12 00
/4 1
/2
12 00
/6 1
/2
12 00
/8 1
12 /20
/1 01
0
12 /20
/1 01
2
12 /20
/1 01
4
12 /20
/1 01
6
12 /20
/1 01
8/
20
01
Resp/None Syndromes
40
35
Rockaways
30
Rest of City
25
20
15
10
5
0
Date
Investigation
 Key Questions
 True increase or natural variability?
 Bioterrorism or self-limited illness?
 Available Methods
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Response team assigned
Response team “Drills down”
Query clinicians / laboratories
Chart reviews
Patient follow-up
Increased diagnostic testing
Investigation
 Chart review in one hospital (9 cases)
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Smoke Inhalation (1 case)
Atypical Chest Pain / Anxious (2 cases)
Shortness of Breath - Psychiatric (1 case)
Asthma Exacerbation (3 cases)
URI/LRI (2 cases)
 Checked same-day logs at 2 hospitals
Increase not sustained
Surveillance can…
Estimate the magnitude of a problem
Determine geographic distribution of illness
Detect epidemics/outbreaks
Generate hypotheses, stimulate research
Evaluate control measures
Monitor changes in infectious agents
Detect changes in health practices
30
25
CASES
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20
15
10
5
0
TIME
Data Sources
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Notifiable diseases
Laboratory specimens
Vital records
Sentinel surveillance
Registries and surveys
Administrative data systems
Other data sources
Reported Cases of Food borne Botulism,
United States, 1981-2001
*Data from annual survey of State Epidemiologists and Directors of State Public Health Laboratories.
Source: CDC. Summary of notifiable diseases. 2001.
Cases of Measles
United States, 1966-2001
Source: CDC. Summary of notifiable diseases. 2001.
Blood Lead Measurements 1975-1981
110
18
Predicted blood lead
100
Lead used
in
90
gasoline
(thousands
of tons) 80
16
Mean
blood
lead
14 levels
 g/dl
Gasoline lead
70
Observed blood lead
12
60
50
10
40
30
1975
1976
1977
1978
1979
1980
1981
8
Year
Source: Pirkle et al JAMA 272:284-91, 1994
Reported Salmonella Isolates,*
United States, 1976-2001
*Data from Public Health Laboratory Information System (PHLIS).
Source: CDC. Summary of notifiable diseases. 2001.
National Notifiable Diseases Surveillance
System (NNDSS) – produces the data in the
MMWR
 The reportable diseases list is revised periodically
by the CSTE/CDC
 States report diseases to the CDC voluntarily
 Reporting is mandated at the state level
 All states report the internationally quarantinable
diseases (i.e., cholera, plague, SARS, smallpox
and yellow fever) in compliance with WHO
International Health Regulations and a varied list
of other diseases
In New Jersey
 Reporting mandated by state law/regulation
 Health care providers, laboratories report to the
LHD (county)
 LHD submits reports to the State
 Reports transmitted by State to CDC primarily
through National Electronic Telecommunications
System for Surveillance (NETSS)
Other NCHS Data Systems for
Surveillance
Vital Statistics
 National Infant Mortality Surveillance (NIMS)
 Linked:
• birth records
• death records
SENSOR
Sentinel
Event
Notification
System for
Occupational
Risks
Recent Occupational Monitoring
Efforts for Sentinel Events Include…
 Biodetection Systems (BDS) in NJ post
offices to detect anthrax and soon, ricin
 Biowatch, an air monitoring system in New
York City and 30 other cities
Weekly Communicable Disease
Reporting System (CDRS) Alerts
 Comparison of current 4-week reporting
period to previous reporting periods;
generated at NJDHSS every Monday
 by disease
 by county
 Increase over baseline (3 SD) triggers an
alert for further investigation
 Limitation: timeliness of reporting into
CDRS
County
Disease
Amebiasis (Entamoeba histolytica)
Cum
Reports
Baseline
4-wk Av
SD
Last 4wk
Period
211
5.5
4.6
8
1,296
40.6
17.6
28
Creutzfeld-Jakob disease
21
1.0
0.0
1
Cryptosporidiosis (Cryptosporidium
spp.)
52
1.8
0.8
1
Encephalitis, West Nile
42
5.6
4.3
2
171
7.1
4.5
3
1,427
51.9
9.9
21
167
4.3
1.9
1
Campylobacteriosis (Campylobacter
spp)
Enterohemorrhagic E. coli O157:H7
Giardiasis (Giardia lamblia)
Haemophilus influenzae - invasive
disease
Flag
√
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√
√
√
New Jersey Real Time Outbreak and Disease Surveillance
OTC Surveillance
Reports Through March 15, 2003
County
ZIP
Category
Sale
Base
Mean
Date 1
Sales in
Date 1
Base
Mean
Date 2
(RODS)
Sales in
Date 2
Base
Mean
Date 3
Sales in
Date 3
Diarrhea
N
3.9
8 (03/11/03)
3.6
4 (03/12/03)
5.3
11 (03/13/03)
Antifever
N
12.4
6 (03/11/03)
11.4
9 (03/12/03)
10.0
20 (03/13/03)
Diarrhea
N
2.7
3 (03/11/03)
3.5
3 (03/12/03)
3.6
8 (03/13/03)
Cough/Cold
N
35.7
30 (03/10/03)
37.8
30 (03/11/03)
18.6
53 (03/12/03)
Cough/Cold
N
44.0
42 (03/10/03)
52.7
45 (03/11/03)
27.0
72 (03/12/03)
Cough/Cold
N
192.6
178 (03/11/03)
193.3
181 (03/12/03)
167.3
191 (03/13/03)
Hydrocortisones
N
2.5
1 (03/10/03)
2.1
2 (03/11/03)
1.7
6 (03/12/03)
Cough
N
11.3
14 (03/11/03)
7.7
13 (03/12/03)
11.3
15 (03/13/03)
Antifever
Y
9.3
9 (03/11/03)
5.1
4 (03/12/03)
3.9
13 (03/13/03)
Antifever
Y
8.8
11 (03/11/03)
7.7
8 (03/12/03)
5.7
20 (03/13/03)
Cipro and Doxycycline
Prescriptions
250000
40000
Cipro
Doxycycline
35000
200000
30000
25000
First anthrax case
reported, 10/4/01.
150000
20000
100000
15000
CDC recommends
doxycyline 10/28/01.
9/11
10000
50000
5000
0
7/1/2001
0
7/29/2001
8/26/2001
9/23/2001
10/21/2001
11/18/2001
12/16/2001
1/13/2002
8/
12
/
9/ 20 0
9
10 /20 0
/7 0
11 /20 0
/4 0
12 /20 0
12 /2/2 00
/3 0 0
0
1/ /2 0 0
27 0
2/ /20 0
24 0
3/ /20 1
24 0
4/ /20 1
21 0
5/ /20 1
19 0
6/ /20 1
16 0
1
7/ /20
14 01
8/ /20
11 0
/ 1
9/ 20 0
8
10 /20 1
/6 0
11 /20 1
/3 0
12 /20 1
12 /1/2 01
/2 0 0
9
1/ /2 0 1
26 0
2/ /20 1
23 0
3/ /20 2
23 0
4/ /20 2
20 0
5/ /20 2
18 0
6/ /20 2
15 0
2
7/ /20
13 02
/2
00
2
Units per 100,000 prescriptions
Tobacco Cessation Aids Sold at a Large
Pharmacy Chain
$0.39
400
$1.42
increase
in City
increase in
tax
State tax
350
300
250
200
150
100
50
0
Week Ending
National Electronic Disease
Surveillance System (NEDSS)
 Will replace NETSS, HIV/AIDS, TB, STD,
vaccine-preventable and infectious
disease reporting systems
 Goal is to standardize health reporting and
link laboratory, hospital and managed care
data
Enhanced and Syndromic Surveillance
 Costs
 Implementation costs are modest
 Operational costs = time of public health staff,
investigations
 Benefits
 Possibily huge if early detection results
 Strengthens traditional surveillance
 Sets high standards for all data collection agencies
Good surveillance does not necessarily ensure
the making of right decisions, but it reduces the
chances of wrong ones.
Alexander D. Langmuir
NEJM 1963;268:182-191
Free Resources
World Health Organization
DISMOD Software
Centers for Disease Control
Epi Info