1. Director Medical Services (Health) Office of the DGMS (Army)
USE OF IMMUNIZATION AS STRATEGY FOR OUTBREAK CONTROL OF VARICELLA ZOSTER IN AN INSTITUTIONAL SETTING
Col VK Bhatti
MD (Community Medicine), M Phil ( Clinical Epidemiology) & PGD Bioethics
Director Medical Services (Health)
Office of the DGMS (Army)
Indian Army

2. Aim of the Presentation
Epidemiological investigation and control strategy undertaken in an Outbreak in health care providers, living in closed institutional setting

3. Background Information
Outbreaks of Varicella common in Children
Outbreak in health care providers living in closed institutional setting uncommon.
Role of vaccination as post exposure prophylaxis for control of outbreak has not been studied extensively.
There was an outbreak involving Nursing cadets in a tertiary care setting

4. Definition of Varicella
Chickenpox (Varicella) is an acute infectious disease caused by exposure to Varicella-zoster virus (VZV) and is characterized by a maculo-papulo vesicular rash; fever and malaise

5. Material and Methods Health Intelligence Div alert
Identification of the Index case.
List of contacts drawn
Screening of contacts & susceptible
Drawing up of epidemiological case sheets

6. Material and Methods (contd..)
Advisory for no contact with patients in hospitals
Aggressive control methods
Blood samples for varicella antibodies
Line listing of cases
Vaccination of all susceptible
Follow up of cases and contacts

7. Results Total of 8 cases occurred
Total cadets in the institute were 156
64 students labelled as susceptible
All susceptible students vaccinated.
All cases were within the incubation period of the index case
No second and third waves seen
DNA isolation showed the causative org to be a wild strain
Svl of pts and other staff in contact with trainees revealed no cases

8. Demographic and clinical characteristics of cases
Demographic/clinical characteristics
(n=8)
Age, years ; mean (range)
19.87 years (18-22)
Gender (% female)
8 (100%)
1st Symptom –
Fever
Rash
Body ache
5 (62.5%)
2 (25%)
1 (12.5%)
6 (75%)
Rash (Generalized)
<50 in number
in number
3 (37.5%)
Malaise
4 (50%)
Complications
Nil

9. Distribution of cases as per training batches

10. Percentages of students with history of chickenpox, vaccination & those susceptible to chickenpox

11. Epidemic Curve
Index case reported on 23rd Nov with Peak of epidemic from 8th to 10th Dec as four cases were reported.

12. Summary
This outbreak occurred among trainee health care workers (HCW) living in an institutional setting
Potential of the outbreak spilling out of control and into patient facility.
Aggressive control measures were instituted to include notification, isolation of cases and vaccination of susceptible
No secondary waves occurred, the vaccine effectiveness can be considered high and vaccination as a control strategy very effective.

13. THANK YOU

14. ANY QUESTIONS ?