foodborne, waterborne and zoonotic infections division
TRANSCRIPT
Foodborne, Waterborne and Zoonotic Infections Division
Foodborne, Waterborne and Zoonotic Infections Division
Syndromic Surveillance Using OTC Medication Sales…How Useful Is
It?
Victoria L. EdgeFoodborne, Waterborne and Zoonotic Infections Division
Infectious Disease and Emergency Preparedness
COMOH/APHEO Education Session for Syndromic Surveillance
1st February 2007
Foodborne, Waterborne and Zoonotic Infections Division
Objectives
C. Understand the role of, and interactions between, public health representatives at different gov’t levels and pharmacists
A. Understand how OTC data are collected and categorised – the importance of researching historical data.
B. Understand the difference between using spatio-temporal patterns of OTC sales as an early warning system and for routine surveillance.
Foodborne, Waterborne and Zoonotic Infections Division
On the Agenda…
• OTC data surveillance
• Public Health Agency of Canada’s (PHAC) use of OTC data
• Features & Utility
• Challenges
• Advantages
Foodborne, Waterborne and Zoonotic Infections Division
OTC Data Surveillance
Foodborne, Waterborne and Zoonotic Infections Division
A. S. A .P.
Alternative Surveillance Alert Project
https://www.cnphi-rcrsp.ca/cnph
Foodborne, Waterborne and Zoonotic Infections Division
Early warning of community outbreaks.
Investigate significant historical Canadian outbreaks.Waterborne :
• Walkerton, Ontario E.coli O157 and Campylobacter
• Battlefords, Saskatchewan Cryptosporidium
Foodborne, Waterborne and Zoonotic Infections Division
Walkerton, Ontario
Spring 2000
Waterborne outbreak: E.coli O157 and Campylobacter
Foodborne, Waterborne and Zoonotic Infections Division
A. S. A .P.
Alternative Surveillance Alert Project
• Meeting with area pharmacists and PHU representatives
• Collection of data – only one pharmacy able to provide electronic data (in weekly format)
• Compared with confirmed (lab) cases from outbreak investigation and also with IGI–related ER visits data
Foodborne, Waterborne and Zoonotic Infections Division
Culture confirmed cases (onset+4days) and Weekly Totals of OTC Culture Confirmed Cases by Onset + 4days and Weekly Totals of
Over-the-Counter Medications Walkerton (March-June2000)
0
10
20
30
40
50
60
70
80
Date
Un
its S
old
0
5
10
15
20
25
30
35
40
45
50
Nu
mb
er
of
Cases R
ep
ort
ed
OTC sales
Cases reported to Health Unit(onset+time lag of 4days)
Heavy rainfall.
(8-12th May)
Start of outbreak
period. (13th May)
Boil water advisory. (21st May)
Start of outbreak
period 13th May
Ref: Edge et al., 2004. Can J Pub Health 95(6):446-450
Walkerton, March-June 2000
Foodborne, Waterborne and Zoonotic Infections Division
Battlefords, Saskatchewan
Spring 2001
Waterborne outbreak: Cryptosporidium
Foodborne, Waterborne and Zoonotic Infections Division
OTC medications related to IGI epidemic curve realized in a retrospective investigation of a waterborne outbreak of
Cryptosporidium.
North Battleford, Saskatchewan Spring 2001
0
5
10
15
20
25
30
35
40
45
50
55
60
01-Mar 10-Mar 17-Mar 24-Mar 31-Mar 07-Apr 14-Apr 21-Apr 28-Apr 05-May 12-May 19-May
Date
#C
ases
epi-linked, unconfirmed (n=929)
confirmed +7day lag
MAR 21
Water system compromised
APR 25
Boil Water Advisory
(Ref: Stirling R, et al. 2001. ) http://www.health.gov.sk.ca/info_center_pub_health_can_epi_report_
NB.pdf
0
5
10
15
20
25
30
35
40
45
50
55
60
01-Mar 10-Mar 17-Mar 24-Mar 31-Mar 07-Apr 14-Apr 21-Apr 28-Apr 05-May 12-May 19-May
Date
#C
ases
0
20
40
60
80
100
120
140
#U
nit
Sale
s
confirmed +7day lag
epi-linked, unconfirmed (n=929)
2001 Sales
MAR 21
Water system compromised
APR 25
Boil Water Advisory
(n=110)
Foodborne, Waterborne and Zoonotic Infections Division
A. S. A .P.
Alternative Surveillance Alert Project
How PHAC uses OTC data
Foodborne, Waterborne and Zoonotic Infections Division
A. S. A .P.
Alternative Surveillance Alert Project
Key Observations from Initial Research:• Keep ‘human involvement’ to a minimum
• Keep it simple : for public health officials
for retailers and pharmacists
• Define benefit: for public health
for retailers and pharmacists
Foodborne, Waterborne and Zoonotic Infections Division
A. S. A .P.
Alternative Surveillance Alert Project
PHAC’s Objectives:• Create and test a system of OTC-sales based surveillance operating at the national level
• Collect data electronically & automatically from major retailers
• Feed all data electronically into one location
• Analyse at different jurisdictional levels as required
Foodborne, Waterborne and Zoonotic Infections Division
Features & Utility
Foodborne, Waterborne and Zoonotic Infections Division
Web-based Data Collection, Analysis and Reporting
https://www.cnphi-rcrsp.ca/cnph
“Canadian Early Warning System” (CEWS)
Foodborne, Waterborne and Zoonotic Infections Division
Currently:
• 6 (almost 7!) major retailers providing data for all of their locations across Canada;
(~2200 locations representing ~50% of all major retailers’ pharmacies)
• PHAC providing wkly reports/alerts to pilot PHUs
• Pilot PHU users have access to web-based monitoring (via CNPHI-CEWS)
• Interaction with PH officials and Pharmacy reps
Foodborne, Waterborne and Zoonotic Infections Division
DATA:
• UPC level daily sales volumes by pharmacy location
• Adult and Paediatric:
anti-diarrhoeal, anti-nauseant, rehydration;
cough and cold products, vaporisers, thermometers
Foodborne, Waterborne and Zoonotic Infections Division
TO DO:
• Enlist more retailers
• Evaluate on-line system by PH & pharmacy officials in next year
Foodborne, Waterborne and Zoonotic Infections Division
Challenges…and Advantages
What’s the Word at the Public Health Region Water Cooler?
Foodborne, Waterborne and Zoonotic Infections Division
“OTC data are not that useful for primary detection.”
“ER visit data are better at earlier detection of disease outbreaks.”
“OTC data are non-specific.”
“Rural areas are poorly represented (if at all) by OTC data.“
Foodborne, Waterborne and Zoonotic Infections Division
HOWEVER,…
In combination with other information…
GBHU Cryptosporidiosis Cases 2006 by Week of Onset
0
1
2
3
4
5
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Week in 2006
# of C
ases
ECADS GI Alert 2 days May 14/15
OTC Sales Alert May 27
OTC Sales Alert Jun 4
ECADS GI Alert 4 days J 14-17
GBHU Alert to EDs re-GI increase - do stool tests J 16
OTC Sales Alerts Aug 2-12
OTC Sales Alert Aug 20-Sept 9
GBHU notifies area HUs & MOHLTC of increase CIOS Alert
posted
With thanks: Dr. Hazel Lynn, Alanna Leffley Grey Bruce Health,
ECADS research team - OTTAWA
Foodborne, Waterborne and Zoonotic Infections Division
A final comment…The very process of investigating OTC sales-based
surveillance has increased the level of communication between pharmacy and public health officials.
Foodborne, Waterborne and Zoonotic Infections Division
Acknowledgements:Public Health Agency of Canada (esp. P Muchaal, J Aramini, S Mukhi)
Walkerton area pharmacists (esp. K. Brown)
Public Health Units: Grey-Bruce, Wellington-Dufferin-Guelph, Kingston Frontenac Lennox & Addington, Waterloo Region,
City of Hamilton, Winnipeg Region)
CRTI funding for CNPHI
PharmaPlus and Rexall (KATZ Group Canada Ltd), Shoppers Drug Mart, Wal-Mart, Loblaw, London Drugs, Safeway
Canadian Association of Chain Drug Stores (CACDS)
University of Guelph
ECADS and the Grey Bruce Health Unit