Overview of Uses for Public Health Surveillance

Daniel M. Sosin, M.D., M.P.H.Division of Public Health Surveillance and

InformaticsEpidemiology Program Office

Public Health Surveillance

Ongoing, systematic collection, analysis, and interpretation of health-related data and dissemination for use in the planning, implementation, and evaluation of public health practice.

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control and prevention measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Shigellosis1968-1998

00

55

1010

1515

YearYear

1968

1968

1973

1973

1978

1978

1983

1983

1988

1988

1993

1993

1998

1998

Rep

ort

ed

cases p

er

100,0

00

pop

ula

tion

Rep

ort

ed

cases p

er

100,0

00

pop

ula

tion

Source: CDC. Summary of notifiable diseases. 1998.

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

TOXIC SHOCK SYNDROME (TSS)United States, 1983-1998

TOXIC SHOCK SYNDROME (TSS)United States, 1983-1998

*Includes cases meeting the CDC definition for confirmed and probable cases for staphylococcal TSS.

1983 1984 1985 1986 1987 1988 19891990 1991 1992 1993 1994 1995 1996 1997 1998

National Center for Infectious Diseases (NCID) data*

National Electronic Telecommunications System for Surveillance (NETSS) data

0

20

40

60

80

100

120

140

160

Year (Quarter)

Rep

ort

ed

cases

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Rate of Hepatitis A United States, 1998

< 5.0< 5.0

5.0–9.95.0–9.9

10.0–19.910.0–19.9 >20.0>20.0

NA

NA

NA

NYCNYC

DCDC

PRPR

VIVI

GUAMGUAM

AM SAMOAAM SAMOA

CNMICNMI

Source: CDC. Summary of notifiable diseases. 1998.

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Botulism (Foodborne) United States, 1978-1998

*Data from survey of state epidemiologists and directors of state public health laboratories. Not yet available for 1998.

*Data from survey of state epidemiologists and directors of state public health laboratories. Not yet available for 1998.

Outbreak caused by potato salad, NM

Outbreak caused by potato salad, NM

Outbreak caused by sautéed onions, IL

Outbreak caused by sautéed onions, IL

Outbreak caused by fermented fish/sea products, AK

Outbreak caused by fermented fish/sea products, AK

Outbreak caused bybaked potatoes, TX

Outbreak caused bybaked potatoes, TX

Laboratory-confirmed cases*Laboratory-confirmed cases*NETSS dataNETSS data

00

1010

2020

3030

4040

5050

6060

7070

8080

9090

100100

110110

YearYear19781978 19831983 19881988 19931993 19981998

Rep

ort

ed

cases

Rep

ort

ed

cases

Source: CDC. Summary of notifiable diseases. 1998.

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

YearYear

Rep

ort

ed

cases

(th

ou

san

ds)

Rep

ort

ed

cases

(th

ou

san

ds)

Vaccine licensedVaccine licensed

00

5050

100100

150150

200200

250250

300300

350350

400400

450450

500500

19631963 19681968 19731973 19781978 19831983 19881988 19931993 19981998

MEASLES — by year, United States, 1983–1998MEASLES — by year, United States, 1983–1998

00

55

1010

1515

2020

2525

3030

YearYear

19831983 19881988 19931993 19981998Rep

ort

ed

Cases

(Th

ou

san

ds)

Rep

ort

ed

Cases

(Th

ou

san

ds)

Source: CDC. Summary of notifiable diseases. 1998.

MEASLES (Rubeola)United States, 1963-1998

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Poliomyelitis (Paralytic)

NOTE: Inactivated vaccine was licensed in 1955. Oral vaccine was licensed in 1961.NOTE: Inactivated vaccine was licensed in 1955. Oral vaccine was licensed in 1961.YearYear

00

55

1010

1515

2020

2525

3030

3535

4040

4545

5050

5555

6060

19681968 19731973 19781978 19831983 19881988 19931993 19981998

Rep

ort

ed

cases

Source: CDC. Summary of notifiable diseases. 1998.

Rate

/10

0,0

00

Pop

ula

tion

Year

Inactivated Vaccine

Oral Vaccine

0.001

0.01

0.1

1

10

100

1000

1951 1956 1961 1966 1971 1976 1981 1986 1991 1996

United States, 1968-1998

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Trends in Plasmid-Mediated Resistance to Penicillin and

TetracyclineUnited States, 1988-1997

Source: Gonococcal

Isolate Surveillance

Project (GISP)

Perc

en

t

0

2

4

6

8

10

12

1988 1989 1990 1991 1992 1993 1994 1995 1996 1997

PPNGTRNG

PPNG & TRNG

Note: "PPNG" (penicillinase-producing ) and "TRNG" (tetracycline-resistant) N. gonorrhoeae refer to plasmid-mediated resistance to penicillin and tetracycline, respectively.

Year

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Breast Cancer Screening

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Foreign-born

Source: CDC. Summary of notifiable diseases. 1998.

Year

U.S.-born

1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998

0

4,000

8,000

12,000

16,000

20,000

Rep

ort

ed

cases

Tuberculosis United States, 1986-1998

(U.S.- and foreign-born persons)

Uses of Public Health Surveillance

Estimate magnitude of the problem Portray the natural history of a disease Determine distribution and spread of

illness Detect outbreaks Generate hypotheses, stimulate research Evaluate control and prevention measures Monitor changes in infectious agents Detect changes in health practices Facilitate planning

Surveillance for Outbreak Detection

Convergence of technology, volumes of electronic data, and new priority for early detection

Increase timeliness and completeness of routine data

Capture nontraditional data that signify a condition before a diagnosis is made

Analytic methods to detect smaller signals

Surveillance for Outbreak Detection: Experience

Laboratory specificity to detect clusters Sentinel systems with resources to

monitor and investigate Syndrome surveillance where outbreaks

are substantial and predictable Case reports trigger outbreak

investigation

Surveillance for Outbreak Detection: Exploration

Enhanced reporting from clinical sites (ED, EMS, 911, offices)

Health care transaction warehouses (pharmacy, patient encounters, lab orders)

Novel data sources (retail sales, veterinary encounters, environmental indicators, absenteeism)

Signal detection methods

Surveillance for Outbreak Detection: Reality

Human “technology” is key Single case detection depends on

clinical acumen and reporting relationships

Epidemiologic judgment in evaluating volumes of data

Follow-up of system signals Tolerance for false alarms will vary

Surveillance Research Needs

Achieving the National Electronic Disease Surveillance System (NEDSS) architecture

Data fusion (linkage) New data sources Case definitions (automation/validation) Geographic Information System (GIS)

indices Forecasting Evaluation and quality control

Resources

www.cdc.gov/cic

www.cdc.gov/epo/dphsi/phs.htm

www.cdc.gov/epo/dphsi/phs/syndromic.htm

dsosin@cdc.gov