Enhanced Varicella Outbreak Surveillance at West Virginia Public Schools Maria del Rosario, MD, MPH Arianna DeBarr, RN, BSN Vaccine Preventable Disease Program December 6, 2017

Objectives Review the epidemiology of varicella Review West Virginia’s past experience with enhanced varicella outbreak surveillance in public schools Describe the proposed plans for enhanced varicella outbreak surveillance in West Virginia public schools  

Varicella (Chickenpox) Etiologic agent Caused by Varicella-zoster virus (VZV) Clinical Presentation Blister-like rash Lesions (>200) in different stages Itchy Fever, malaise Starts on stomach, back, and face spreading to body

Transmission Person-to-person by: Respiratory route (breathing in aerosols) Direct contact with virus particles Infected person is infectious one to two days before the rash appears until all lesions form scabs (five to seven days) Very contagious Secondary attack rate in susceptible household contacts = 85% (61%-100%)

Complications Often seen among infants, adults, and immunocompromised Bacterial infections Pneumonia Encephalitis Hemorrhagic conditions

Breakthrough Varicella Infection with wild-type varicella occurring >42 days after vaccination Contagious 15%-20% of one-dose vaccinated persons exposed to VZV Mild disease <50 lesions Low to no fever Shorter rash duration Fewer vesicles Mostly maculopapular instead of vesicular 25%-30% of Breakthrough Varicella cases are not mild

Reportable Varicella

Reportable Varicella (cont’d)

Temporal Trend of Varicella

Vaccine Effectiveness Study Background and Methods Federally funded (American Recovery Reinvestment Act) January 2010 to May 2011 Purpose: evaluate 2-dose varicella vaccine effectiveness (VE) All West Virginia public schools (n=688) Respondents: school nurses (n=220) Case control = 1:3 Reference: PIDJ, 2014. November; 33 (11): 1164-1168.

Vaccine Effectiveness Study (cont’d) Results Total cases = 133 cases, 365 controls Vaccine effectiveness (VE) against ALL varicella: Varicella vaccine VE 95% CI One-dose 83.2% 69.2% 90.8% Two-doses 93.9% 86.9% 97.1% Two-doses vs. One-dose 63.6%* 32.6% 80.3% *incremental VE

Vaccine Effectiveness Study (cont’d) Results Vaccine effectiveness (VE) in preventing moderate/severe varicella: Breakthrough cases with one dose and two doses had milder rash compared with unvaccinated cases Varicella vaccine VE 95% CI One-dose 88.2% 72.7% 94.9% Two-doses 97.5% 91.6% 99.2% Two-doses vs. One-dose 78.6% 40.9% 92.3%

Outbreak and Vaccine Effectiveness Study Background 2007: Two-dose varicella vaccine program adopted in United States to decrease disease and prevent outbreaks Methods Nine states’ (including West Virginia) health departments Varicella outbreaks reported to Centers for Disease Control and Prevention (CDC), 2005-2012 Outbreak setting Number of cases per outbreak Vaccination status Laboratory confirmation Source: PIDJ, 2015 Oct; 34(10): 1105-1109

Outbreak and Vaccine Effectiveness (cont’d) Findings 2005-2012: 929 outbreaks reported 95% of outbreaks reported from schools Decline in number of outbreaks by 78% 2005 = 147 outbreaks 2012 = 33 outbreaks Decrease in size of outbreak Median size 2005-2006 = 12 Median size 2010-12 = 7 Decrease in duration of outbreak Median duration 2005-2006 = 38 days Median duration 2010-2012 = 26 days

Local Health Department What Where When How Varicella aggregate counts Through West Virginia Electronic Data Surveillance System (WVEDSS) Weekly WVEDSS - varicella reporting form Varicella outbreaks To the Department of Health & Human Resources, Division of Infectious Disease Epidemiology (DIDE) Immediately after notified Phone call to the on-call epidemiologist

West Virginia Public School Nurses What Where When How Aggregate varicella counts To Local Health Department (LHD) Weekly Via fax or phone call Varicella outbreaks To LHD Immediately Phone call Survey on varicella outbreaks Submit to DIDE Monthly SurveyMonkey Excel spreadsheet with varicella case counts Attached to

Excel Spreadsheet

State Health Department What Where When How Send out survey To West Virginia Public School Nurses Monthly Through SurveyMonkey Assess data from school nurses Export to excel file Assess varicella aggregate reporting WVEDSS Bi-Monthly Excel file exported from WVEDSS Provide feedback Email Bi-Monthly to Regional Epidemiologists and LHDs Monthly to school nurses

Varicella Aggregate Reporting Enhanced Varicella Surveillance Varicella Reporting Description Varicella Aggregate Reporting Enhanced Varicella Surveillance Why it is required West Virginia Reportable Disease Rule Vaccine Preventable Diseases grant requirement Target population All healthcare providers, school nurses, healthcare facilities All students (k-12) in West Virginia public schools Who collects data LHD Nurses School Nurses Frequency of data collection Weekly How data is submitted Through the WVEDSS Through SurveyMonkey with an excel spreadsheet attached Frequency of reporting Weekly - every Monday with previous week’s count Weekly to LHD Monthly to DIDE Number of reports submitted One report per county One report per school

Purpose 2017-2018 Improve knowledge of the epidemiology of varicella Assess virus transmission patterns Describe disease burden and risk factors for severe varicella Provide estimates of varicella vaccine effectiveness Identify risk factors for the vaccine failure Monitoring varicella outbreaks Assess the impact of second-dose vaccine recommendation Facilitate the development and refinement of appropriate public health interventions

Enhanced Varicella Survey

Enhanced Varicella Survey (cont’d)

Enhanced Varicella Survey (cont’d)

Enhanced Varicella Survey (cont’d)

Enhanced Varicella Survey (cont’d)

Enhanced Varicella Survey (cont’d)

Enhanced Varicella Survey (cont’d)

Contact Arianna DeBarr, BSN, RN Vaccine Preventable Disease Nurse West Virginia Department of Health and Human Resources Bureau for Public Health Office of Epidemiology and Prevention Services Division of Infectious Disease Epidemiology Phone: (304) 356-4014 Fax: (304) 558-8736 Email: Arianna.S.DeBarr@wv.gov Here is my contact information and for more information on AFM please visit our website at www.dide.wv.gov

Contact Maria del Rosario, MD, MPH Director of Surveillance West Virginia Department of Health and Human Resources Bureau for Public Health Office of Epidemiology and Prevention Services Division of Infectious Disease Epidemiology Phone: (304) 558-5358 Fax: (304) 558-8736 Email: Maria.C.delRosario@wv.gov Here is my contact information and for more information on AFM please visit our website at www.dide.wv.gov