From Data to Signals to Screenshots: Recent Developments in NYCDOHMH

ED Syndromic Surveillance.

Marc Paladini

New York City Department of Health and Mental Hygiene

Questions

• What are we looking for?

• How are we looking for it?

• What do we need to find it?

• What do we do after we find it?

• How does this help us do our job more effectively?

Outline

• Introduction to NYC emergency department syndromic surveillance.– Analysis– Signal Investigation

• Data Visualization

• Future Directions

Analysis

Hospital map

ED Syndromic Surveillance in NYC

• Chief complaint – hierarchical syndrome coding• Syndromes:

– 1. Sepsis– 2. Respiratory– 3. Rash– 4. Fever– 5. Cold– 6. Diarrhea– 7. Asthma– 8. Vomit– Other

Hospital Statistics - 2005

• 3,136,772 total visits. (7000-10,000 / day)syndrome number percent

other 2351837 74.98%

sepsis 16968 0.54%

respiratory 258946 8.26%

rash 61352 1.96%

fever 184034 5.87%

cold 54387 1.73%

diarrhea 51027 1.63%

asthma 75566 2.41%

vomit 82655 2.64%

Data Analysis

• Ratio of syndrome/other• Citywide and spatial (zip code, hospital)• Age 13+: respiratory and fever• All ages: diarrhea and vomit• Age group

– 0-4– 5-17– 18-59– 60+

• 7 days/week

SIGNALS

Syndromic Analyst

• Run surveillance – usually @ 2 hours

• Review output for signals

• Review signal details– Linelist– Baseline vs. signal frequency tables

• Consult with DOH Physician on call (Cluster Doc)

Cluster Doc

• Review data with analyst

• Ask for further details

• Decide on follow up– guidelines/protocol– “fingerprint” of signal

Signals – 2005

syndrome City Hospital Ziprespiratory 17 3 1fever 11 10 7diarrhea 28 8 6vomit 23 10 10

Investigation of Signals

• Review line list• Check complimentary systems• Acquire interim data (12 hour log)• Call to EDs• Chart reviews• Patient follow up (phone calls)• Augment lab testing/collect specimens• On site epi teams• Special studies (case-control)

Routine Steps

• First day (Resp/Fev) vs. 2nd day (Vom/Dia)• Perform descriptive statistics, midday log• Examine CUSUM, other systems• Call hospitals with CUSUM alarms

– What did they see yesterday?– What are the seeing today?– Clinical clusters, unexpected severe illness?– Augment lab testing

• Alert ED staff

Concerning Features of a Syndromic Signal

• Sustained• Multiple hospitals • Large number of excess cases • Uniformity of chief complaints• Young adults or age/sex clustering • Overlapping syndrome signals • Coincident clinician call • Coincident with high profile public event• Concordance with other surveillance systems

Results of Investigations

• Some clear seasonal patterns evident

• Sharp spikes associated with known events

• Rich ecological associations

• Difficult to investigate

• Used to reinforce public health messages (influenza, viral GI, heat wave, blackout, asthma)

Proposed Prospective Investigation Protocol

• All significant resp and fever signals

• Chart reviews

• Patient interviews

• Classify if cases in signal are related– by lab diagnosis, i.e. strep pharyngitis– by clinical diagnosis, i.e. pharyngitis– by risk factor, i.e. subway travel

DATA VISUALIZATION

Intranet

Respiratory intranet

Signal details 1

Signal details 2

Signal details 3

Signal details 4

FUTURE DIRECTIONS

ILI age 1

ILI age 2 - serfling

ILI age 3 - TERS

ILI age 4 - daily

Resp CC

Fev/resp/resp non-feb

Febrile Respiratory, Fever and Non-febrile Respiratory Syndromes. Weekly ratio. Log Scale.

0.001

0.01

0.1

1

1/5/

2002

2/9/

2002

3/16

/200

24/

20/2

002

5/25

/200

26/

29/2

002

8/3/

2002

9/7/

2002

10/1

2/20

0211

/16/

2002

12/2

1/20

021/

25/2

003

3/1/

2003

4/5/

2003

5/10

/200

36/

14/2

003

7/19

/200

38/

23/2

003

9/27

/200

311

/1/2

003

12/6

/200

31/

10/2

004

2/14

/200

43/

20/2

004

4/24

/200

45/

29/2

004

7/3/

2004

8/7/

2004

9/11

/200

410

/16/

2004

11/2

0/20

0412

/25/

2004

1/29

/200

53/

5/20

054/

9/20

055/

14/2

005

6/18

/200

57/

23/2

005

8/27

/200

510

/1/2

005

11/5

/200

512

/10/

2005

1/14

/200

6

Sum of RRespnofev Sum of Rfevflu Sum of RRfev

Diar/vom age 0-4

Diarrhea and Vomit Syndromes Age 0 - 4. Weekly Ratio.

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

1/5/

2002

2/9/

2002

3/16

/200

24/

20/2

002

5/25

/200

26/

29/2

002

8/3/

2002

9/7/

2002

10/1

2/20

0211

/16/

2002

12/2

1/20

021/

25/2

003

3/1/

2003

4/5/

2003

5/10

/200

36/

14/2

003

7/19

/200

38/

23/2

003

9/27

/200

311

/1/2

003

12/6

/200

31/

10/2

004

2/14

/200

43/

20/2

004

4/24

/200

4

5/29

/200

47/

3/20

048/

7/20

049/

11/2

004

10/1

6/20

0411

/20/

2004

12/2

5/20

041/

29/2

005

3/5/

2005

4/9/

2005

5/14

/200

5

6/18

/200

57/

23/2

005

8/27

/200

510

/1/2

005

11/5

/200

512

/10/

2005

1/14

/200

6

Sum of Rvom Sum of Rdiar

Fev resp/fev cold

Febrile Respiratory and Cold Syndrome Visits.Weekly Ratio.

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

1/5/

2002

2/9/

2002

3/16

/200

24/

20/2

002

5/25

/200

26/

29/2

002

8/3/

2002

9/7/

2002

10/1

2/20

0211

/16/

2002

12/2

1/20

021/

25/2

003

3/1/

2003

4/5/

2003

5/10

/200

36/

14/2

003

7/19

/200

38/

23/2

003

9/27

/200

311

/1/2

003

12/6

/200

31/

10/2

004

2/14

/200

43/

20/2

004

4/24

/200

45/

29/2

004

7/3/

2004

8/7/

2004

9/11

/200

410

/16/

2004

11/2

0/20

0412

/25/

2004

1/29

/200

53/

5/20

054/

9/20

055/

14/2

005

6/18

/200

57/

23/2

005

8/27

/200

510

/1/2

005

11/5

/200

512

/10/

2005

1/14

/200

6

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

Sum of RRfev Sum of RCLD_fev

Questions and Projects

• What are we looking for?• Are more fields better?

– Discharge diagnosis / ICD-9 code– Disposition– Recorded temperature

• Quantify effect of school closings• Day of Week• SaTScan mapping• Age as space