1. JE surveillance in Sri Lanka
country presentation for the 5th Bi-regional meeting on JE
prevention and control
Dr. Pushpa Ranjan Wijesinghe
National Surveillance Focal Point
Epidemiology Unit, Ministry of Health

2. Uses of surveillance data
• Quantification of the disease frequency in the country
– Information from 1985 to date
• Identification of JE endemic areas in the country
– Phase based immunization in 1989
• Identification of high risk groups for targeted vaccination
– 1-10 age group till 2009
• Forecasting and Identification of JE outbreaks
– Last major outbreak in 2002 (Ratnapura)
• Designing and implementation of the JE control programme
– Vector control and IEC before 1889
– Immunization program from 1989
•
Evaluation of the JE control programme

3. Current use of surveillance data
• Determination of the changing epidemiology
–
–
–
–
Sporadic nature of cases since 2003
Changing age profile of JE cases
Spatial change in disease transmission among humans
Effectiveness of the immunization campaign
• Verification of mounting rumors and anecdotal evidence that JE is
on rise
– Clinical fraternity , media
• Appraisal of the effectiveness of the LJEV
– Is the efficacious vaccine effective in the real world ?
– Is one dose strategy the correct approach ?

4. Methods of Acute Encephalitis
Syndromic surveillance
• Routine communicable disease surveillance
–
–
–
–
–
–
Acute Encephalitis - a notifiable disease
Notification by all medical practitioners
Notification on the basis of the tentative diagnosis
Availability of surveillance case definition
100% field investigation by the Public Health Inspector
Information to the national data base through the
“weekly Return of Communicable Disease “
– Feed back of weekly consolidated information through
the “ Weekly Epidemiological Report”

5. Methods of Acute Encephalitis
Syndromic surveillance
• Event Based Surveillance
– Media surveillance for reported communicable
disease outbreaks / clusters at the national level
– Central rumour register
– District rumour registers maintained by Regional
Epidemiologists
– Confirmation by the peripheral staff
– Event assessment by the Regional Epidemiologist
with central support

6. Methods of Acute Encephalitis
Syndromic surveillance
• Case–based Special Surveillance
– Case based surveillance of all AES cases including JE
– Obtaining in-depth information than through routine
notification
• Demographic, epidemiological, clinical , immunization and
risk factors
– 100% mandatory investigation of JE cases
– Entry into the National JE registry
– Quarterly Feed back in the Quarterly Epidemiological
Bulletin
– Annual surveillance information through the Annual
health bulletin

7. Methods of Acute Encephalitis
Syndromic surveillance
• Laboratory surveillance
– Sentinel hospitals based
– National JE Reference Laboratory - Viral
Laboratory at the Medical Research Unit
– Accredited laboratory
– Tests used
• Detection of Ig M in serum and CSF

8. EPIDEMIOLOGICAL INFORMATION

10. JE specific morbidity Rate [per 100,000] & Case
Fatality Ratio (%), 1985-2010
100
10
1
85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 0
Morbidity
0.1
CFR
1
2
3
4
5
6
7
8
9 10

11. Distribution of suspected and confirmed JE cases
Confirmed JE
Year
Suspected
No.
%
2006
130
26
20.0
2007
203
39
19.2
2008
261
31
11.8
2009
223
34
15.2
2010
215
27
12.5

12. Results of laboratory surveillance
Total Number of AES Specimens
Received in Lab
Number of Positive
Results
Year
Serum
CSF
Serum
CSF
Received
Tested
Received
Tested
JE Positive
JE
Positive
2009
142
142
568
568
15 ( 9.4%)
23 ( 4.1%)
2010
168
168
558
558
8( 4.7%)
19 (3.4%)
2011
43
43
187
187
3( 6.9%)
12( 6.4%)

13. Seasonal trend of AES reporting in Sri Lanka
2006
2007
50
45
40
35
30
25
20
15
10
5
0
2008
2009
2010
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

14. Seasonal trend of JE reporting in Sri Lanka
16
14
12
2006
10
2007
8
2008
6
2009
2010
4
2
0
Jan
Feb
Mar
Apr
May
June
July
Aug
Sep
Oct
Nov
Dec

15. Spatial distribution of suspected and confirmed JE 2010
Reported AES cases
Confirmed JE cases

16. Age distribution of confirmed JE cases
Age group
Year
2006
2007
2008
2009
2010
<1 year
01(03.8%)
1 (2.6%)
0 (0.0%)
2(5.9%)
1(3.7%)
1-4
03(11.4%)
3 (7.8%)
1 (3.2%)
4(11.8%)
6(22.2%)
5-9
00 (0%)
2 (5.2%0
1(3.2%)
2(5.9%)
1(3.7%)
10-14
3 (11.4%)
3 (7.8%)
1(3.2%)
2(5.9%)
1(3.7%)
15-19
1(3.8%)
1 (2.6%)
2 (6.4%)
2(5.9%)
2(7.4%)
20-24
1(3.8%)
3 (7.8%)
5(16.0%)
6(17.5%)
1(3.7%)
25-29
1(3.8%)
0 (0%)
1 (3.2%)
3(8.8%)
1(3.7%)
30-34
1(3.8%)
6 (15.6%)
1(3.2%)
3(8.8%)
3(11.1%)
35-39
1 (3.8%)
2 (5.2%)
1(3.2%)
0(0.0%)
1(3.7%)
40-44
0(0%)
1(2.6%)
3 (9.6%)
1(2.9%)
0(0.0%)
45-49
3(11.4%)
2 (5.2%)
3 (9.6%)
3(8.8%)
0(0.0%)
50-54
3 (11.4%)
5 (13.0%)
0 (0.0%)
1(2.9%)
3(11.1%)
55-59
1(3.8%)
1(2.6%)
2 (6.4%)
1(2.9%)
2(7.4%)
>60
4(15.2%)
5 (13%)
7(22.4%)
2(5.9%)
5(18.5%)
Unknown
3(11.4%)
4 (10.4%)
2 (6.4%)
2(5.9%)
0(0.0%)
Total
26
39
31
34
27

17. Confirmed JE cases by immunization status

18. Challenges
• Waning interest of the policy and decision makers on
JE
– declined disease burden
– competing priorities
• Improving the quality of surveillance information
related to auxiliary laboratory investigations
• Improving the coverage of specimens sent for
confirmation of JE from sentinel hospitals
• Sustainable logistics supply to the national reference
laboratory
• Improvement of etiological diagnosis of AES other
than JE
• Establishing sustainable private sector reporting

19. Solutions
• Quarterly surveillance reviews at the
– Advisory Committee of Communicable Diseases
– Quarterly meeting of Regional Epidemiologists
– District level reviews by Regional Epidemiologists
• Mandatory investigation by Medical officers of Health
• 100% case- based investigation for all confirmed JE cases
• Complimentary lab information from the sentinel
hospitals
• Discussions with the clinicians and professional bodies
• Back up funding from cost-savings and donor agencies
• Proposed new system of mandatory reporting of
aetiology by virologists and microbiologists for all tested
AES specimens

20. Acknowledgements
• Dr. Paba Palihawadana – Chief Epidemiologist
• Dr.T.S.R. Pieris – EPI focal point
• Dr.Geethani Galagoda - JE laboratory focal point
, MRI – Colombo
• Dr. Chatura Edirisuriya – Registrar in Public
Health
• Nipuni, Roshan and Inoka - JE surveillance team
• Dr. Nihal Abeysinghe -WHO/SEAR