Background (1)
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Transcript of Background (1)
Middle East Consortium on Infectious Disease Surveillance (MECIDS)
Regional network for laboratory-based surveillance of foodborne diseases
Background (1)
• Globalization of food and centralization of its production have important economic advantages
• However, under these circumstances, accidental or deliberate contamination of food can lead to epidemics that can affect large populations.
• Exposure to a high infective dose of enteropathogens may significantly increase complication and fatality rates, especially among young children and aged people.
Background (2)
• Many scientific articles describing naturally occurring epidemics of foodborne diseases including national and even international spread of enteropathogens.
• A few reports on incidents in which intentionally contaminated food caused outbreaks of shigellosis and salmonellosis in the USA
• Two review papers assessed the threat of bioterrorism on the food supply
• Foodborne pathogens were classified by the CDC as a category 2-level candidates for being used as bio-weapons
Background (3)
Solution• To establish enhanced surveillance networks to
provide baseline information against which clusters of disease can be identified.
• To obtain information on the microbial etiology of the disease and on the phenotypic and genotypic characterization of the recovered agents
• To link laboratory data with variables related to the ill subjects
Goal and Rationale (defined by MECIDS members)
• Goal: To establish a regional system of surveillance of foodborne diseases in the Middle East.
• Rationale: In view of the close proximity among the 3 countries and a level of food exchange that hopefully will increase in the near future it was anticipate that the significant upgrading in the methods of surveillance will play an important role in the prevention and control of occurrence and transmission of foodborne diseases in the whole region.
Overall objectives
• To establish or enhance of national laboratory-based surveillance networks for foodborne diseases in Jordan, Israel and the Palestinian Authority
• To use harmonized methodology• To develop a common platform of communication,
data sharing and analysis• To discuss intervention steps when needed.
What happened next ?
• A detailed joint protocol and budget based on these goal and objectives was submitted by the 3 countries to SFCG and NTI.
• Due to paucity of funds, NTI and SFCG committed to support just one year of initial activities in each of the 3 countries that will focus on one of the foodborne pathogen (Salmonella). It was agreed that in this framework each country will outline its specific objectives that will fit the overall goal of the establishment of the regional foodborne
diseases surveillance network.
Middle East Consortium on Infectious Disease Surveillance (MECIDS)
Laboratory-based surveillance of foodborne diseases
Report on activities conducted in Israel (Dec 2004-March 2006)
Objectives for the first year (1)
• Collect Salmonella data at selected sentinel laboratories and improve the transfer of data to the central data analysis unit.
• Improve phenotypic and genotypic characterization of Salmonella, Shigella and other foodborne pathogens.
• Perform a case-control study to identify risk factors of salmonellosis due to infection with Salmonella virchow, which is an emergent Salmonella pathogen in Israel, and potentially in the Middle East as a whole.
• Conduct a nationwide population based survey to estimate the burden of foodborne infections and assess the level of under reporting in Israel.
Objectives for the first year (2)
• Perform a survey among physicians to assess their knowledge and practice (KAP) regarding foodborne diseases.
• Transfer electronically national data on a monthly basis to the regional data depositary unit at CMC Amman.
• Share data and analysis on foodborne diseases among all MECIDS participants.
Structure of the network in Israel
• Sentinel Laboratories: 9 laboratories all over Israel (hospital and community)
• Central Lab: Central MOH Laboratory in Jerusalem and Research Lab at Dept. of Epidemiology, Tel Aviv University
• Data analysis unit : (MOH Israel Center for Disease Control and Dept. of Epidemiology, Tel Aviv University )
Stool cultures performed at the sentinel laboratories (Jan. 05-March 06)
January 05 5372
February 05 4721
March 05 5455
April 05 4171
May 05 6174
June 05 6264
July 05 6244
August 05 6959
September 05 6312
October 05 4943
November 05 5735
December 05 4759
January 06 4244
February 06 4144
March 06 4409
Total 79906
Salmonella isolates (n=824) from stool specimens at the 9 sentinel laboratories from January 2005 to March
2006
0
5
10
15
20
25
30
35
40
45
50
Jan-
05
Feb-
05
Mar-
05
Apr-05 May-
05
Jun-
05
Jul-05 Aug-
05
Sep-
05
Oct-05 Nov-
05
Dec-
05
Jan-
06
Feb-
06
Mar-
06
Month
Nu
mb
er o
f Is
ola
tes
North (C)North (C+H)Central (C)Central 2 (C)
Central (H)Jerusalem (H's)Jerusalem (C)South (C+H)
Salmonella isolates at all the sentinel labs between January 2005 and March 2006
0
10
20
30
40
50
60
70
80
90
100
Jan-05 Feb-05 Mar-05 Apr-05 May-05 Jun-05 Jul-05 Aug-05 Sep-05 Oct-05 Nov-05 Dec-05 Jan-06 Feb-06 Mar-06
Month
Num
ber o
f Iso
late
s
Percentage of Salmonella isolated at the various sentinel labs
(all isolates from January 2005 to March 2006)
North (C)14.9%
North (C+H)5.9%
Central (C)14.9%
Central 2 (C)16.4%
Jerusalem (H's)8.6%
Jerusalem (C)16.7%
South (C+H)20.9%
Central (H)1.6%
Isolation rate of Salmonella at the sentinel labs during the surveillance period
0
0.2
0.4
0.6
0.8
1
1.2
1.4
Jan-05 Feb-05 Mar-05 Apr-05 May -05 Jun-05 Jul-05 Aug-05 Sep-05 Oct-05 Nov -05 Dec-05 Jan-06 Feb-06 Mar-06
Month
Iso
latio
n R
ate
per
100
Mean isolation rate by sentinel lab (Jan 05-March 06)
0.73 0.68
0.86
0.25
0.74
1.09 1.06
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
North(C+H)
North (C) Central 2(C)
Central (H) Jerusalem(H's)
Jerusalem(C)
South(C+H)
Lab
Iso
latio
n R
ate
per
100
Distribution of Salmonella isolates by age (isolates of the period January- December 2005)
18.7%
37.5%
7.3%4.1%
14.0%
9.5% 8.9%
0.0%
5.0%
10.0%
15.0%
20.0%
25.0%
30.0%
35.0%
40.0%
45.0%
<1 1-4 5-9 10-14 15-44 45-64 >=65
Age Group
Iso
late
Pe
rce
nta
ge
Distribution of Salmonella isolates in the first 5 years of life
Number of isolates
(%)
0 128 (33.2%)
1 140 (36.4%)
2 66 (17.1%)
3 32 (8.3%)
4 19 (4.9%)
Total 385 (100.0%)
Distribution of Salmonella isolates by gender and age group (Jan. 05-Dec. 05)
Age group Females(%) Males(%) Total
1> 62) 18.0%( 66) 19.5%( 128) 18.7%(
1-4 119) 34.5%( 137) 40.5%( 256) 37.5%(
5-9 22) 6.4%( 28) 8.3%( 50) 7.3%(
10-14 13) 3.8%( 15) 4.4%( 28) 4.1%(
15-44 59) 17.1%( 37) 11.0%( 96) 14.1%(
45-64 36) 10.4%( 29) 8.6%( 65) 9.5%(
65<= 34) 9.9%( 26) 7.7%( 60) 8.8%(
Total 345) 100.0%( 338) 100.0%( 683) 100.0%(
Distribution of Salmonella isolates by serogroup
1
160
207
132
233
16 311
43
0
100
200
300
400
500
600
Salmonella A Salmonella B Salmonella C1 Salmonella C2 Salmonella D Salmonella E Salmonella F Salmonella G Salmonella Spp.
Salmonella Serogroup
Nu
mb
er o
f Is
ola
tes
Five most often isolated Salmonella serotypes (Jan 05-Dec05)
Salmonella serotype Number of Isolates (%)
S. Enteritidis 185) 23%(
S. Typhimurium 57) 7%(
S. Virchow 72) 9%(
S. Hadar 48) 6%(
S. Infantis 35) 4%(
Others 392) 51%(
Total 789) 100.0%(
The five most common Salmonella serotypes by age group (Jan 05-Dec05)
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
Iso
late
s P
erce
nta
ge
<1 1-4 5-9 10-14 15-44 45-64 >=65
Age Group
S. Enteritidis
S. Typhimurium
S. Virchow
S. Hadar
S. Infantis
Phage types of S. Typhimurium in a subsample (n=26) of S. Typhimurium isolates
Group238.5%
R97.7%
Group130.8%
2 (4+)23.1%
Phage types of S. Enteritidis in a subsample (n=65) of S. Enteritidis isolates
F330.8%
B340.0%
C820.0%
F19.2%
Population survey on the burden of diarrheal diseases
• We conducted a nationwide population based survey to estimate the burden of diarrheal diseases among children and adolescents and assess the level of under reporting in Israel.
• A telephone based population survey was conducted during August, September and October 2005.
• 3141 phone number have been selected randomly from all the phone books of Israel.
Flow chart of households selection process
3141Phone calls
6% (189)Business / Fax
12.8% (401)Non-working
phone numbers
56.3% (1769)Households participated
19.9% (626)Refused to participate
4.9% (156)No answer
38.4% (680)Households with al least
one child under 17
61.6% (1089)Households without a
child under 17
7.2% (49)Households with at least one child with diarrhea
92.8% (631)Households without any
child with diarrhea
The chain of events from occurrence of cases of diarrhea in the general population to reporting
Reporting
Positive laboratory cultures
Provided a stool specimen for culture
Asked to provide a stool specimen
Visited a physician 38.8% 38.8%
21.2% 8.2%
100% 8.2%
4.28% 0.35%
0.22%63.5%
Subjects with diarrhea 100% 100%
Rate Cumulative
Factors associated with
Physicians‘ Decision to
Request the Performance of
Stool Cultures
from Patients with Diarrhea
Objectives1. To determine what proportion of physicians
requests in Israel the performance of stool cultures from patients with diarrhea.
2. To determine what patient and physician-related characteristics are associated with a stool culture request.
3. To estimate and characterize biases in morbidity data based on culture-proven cases of foodborne diseases.
Methods• The study was conducted in collaboration
with one of the Health Maintenance Organization (H.M.O.) operating in Israel.
• We performed a survey through questionnaires distributed among pediatric physicians.
Collection of questionnaires from the physicians approached and the level of compliance
444 Questionnaires sent
141 Returned the questionnaire
286 Didn't return the questionnaire
153 Phone connections established
7 Refused to participate
146 Asked again to return the questionnaire
80 Returned the questionnaire
66 Didn't return the questionnaire
17 Left the HMO Maccabi
Proportion of pediatricians determined by the various factors to request a stool culture
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
Fever above 30oC
Bloody diarrhea
Abdom
inal pain
Dehydration
Associated w
ith an outbreak
Recent travel to developing country
Diarrhea for >3 days
Repeated com
plaint
Imm
une-comprom
ised
Proxim
ity to the specimen collection site
Age
The relative importance of various factors in the physicians' decision to order a stool culture
Proximity to the specimen
collection site 0%
Fever above 30oC 2%
Age 3%
Bloody diarrhea 71%
Associated with an outbreak 3%
Abdominal pain 1%Dehydration 1%
Recent travel to developing country 3%
Diarrhea for >3 days 9%
Immune-compromised 3%
Repeated complaint 4%
Risk Factors for Enteric Infections Caused by Salmonella Virchow among
young children in Israel
A Matched Case Control Study
Finished, data will be shared shortly