Effectiveness of monovalent rotavirus vaccine in the Philippines 13 th Rotavirus Symposium, 29 Aug 2018, Minsk, Belarus

Transcription

1 Effectiveness of monovalent rotavirus vaccine in the Philippines 13 th Rotavirus Symposium, 29 Aug 2018, Minsk, Belarus Anna Lena Lopez, MD, MPH Director, Institute of Child Health and Human Development, University of the Philippines Manila

2 Outline Introduction Methods Results Summary Declaration: I have no conflicts of interest.

3 INTRODUCTION

4 The Philippines Lower middle income country - GDP of 2,989.0 current USD Estimated Population, million

5 Rotavirus Accounts for ~40% of diarrheal hospitalizations in children <5 years worldwide Philippines: Diarrhea is the 2 nd leading cause of death in children 1-4 years of age and 8 th leading cause of death in infants a In 2013, Estimated 5,169 diarrhoea deaths, 50% were due to rotavirus or 2,599 deaths among children <5 years b 2017:1,394 (35%) confirmed cases a 2014 Health statistics b Tate J, et al. Clinical Infectious Diseases 2016;62(S2):S96 105

6 Rotavirus vaccine use in the Philippines 2006 Recommended by the Pediatric Society for the private sector in the Philippines for routine infant immunization; Private sector coverage according to EPI is estimated to be <10% of eligible population 2012 DOH announced inclusion of rotavirus vaccine in the EPI for babies aged 6 weeks to 15 weeks to receive the first dose in families from the poorest quintile 2014 Limited to 2 regions for effectiveness evaluation 2015 Further limited to one region (CARAGA region) to babies aged at least 6 weeks for the first dose. The second dose given at least 4 weeks after the 1st dose, together with second dose of Pentavalent and OPV, as long as less than 2 years of age.

7 Rotavirus Vaccine Effectiveness Evaluation Objective: To estimate the effectiveness of rotavirus vaccine in the Philippines Conducted within an ongoing rotavirus surveillance Rotavirus Surveillance Established in 2012 in 7 sentinel hospitals CARAGA Region (Region 13) had highest number of diarrhea cases reported

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9 Rotavirus vaccination in Agusan del Sur September 2012 RV vaccine provided to infants in the poorest quintile in Agusan del Sur January 2013 RV vaccination expanded to all ageeligible children in two municipalities in Agusan del Sur, San Francisco and Prosperidad, regardless of socioeconomic status. July 2014 RV vaccination further expanded to all ageeligible children in the whole province Vaccine stock-outs occurred in October 2013 to June 2014 and from June 2016 to April 2017.

10 METHODS

11 Design: Test-negative case-control Within the rotavirus surveillance platform of D.O. Plaza Memorial Hospital Inclusion: Children aged <5 years who underwent treatment for acute diarrhea in DOPH were included in the surveillance Eligible to have received the rotavirus vaccine Resident of Agusan del Sur Methods

12 Definitions Acute diarrhea defined as the passage of three or more loose or watery stools within a 24-hour period for 14 days. Case-patients children enrolled in the active surveillance platform, who tested positive for RV by ELISA, and were age-eligible to have received RV vaccine. Controls children enrolled in the active surveillance platform who tested negative for RV by ELISA, and were age-eligible to have received RV vaccine.

13 RESULTS

14 Results From September 2014 to August 2016, screened 967 children Enrolled 600 children with stools tested for rotavirus and immunization status were confirmed 203 (34%) tested positive for RV Rotavirus Positive Rotavirus Negative n=203 (%) n=397 (%) p- value Median age in months (range) 11 (1-51) 11 (1-47) 0.07 Male 116 (57%) 233 (59%) 0.72 Household enrolled in 33 (16%) NHTS 60 (15%) 0.71 Median number of people in household 5 (3-14) 5 (3-15) 0.09 Mother s current age 29 (15-29 (16-47) (range) 47) 0.33 Mother's education level 0.28 Primary school 45 (22%) 90 (23%) Secondary school 131 (65%) 246 (62%) Post-secondary 15 (7%) 21 (5%) University or above 12 (6%) 40 (10%)

15 Clinical characteristics of enrolled children Rotavirus Positive Rotavirus Negative n=203 (%) n=397 (%) p-value Duration of diarrhea days 43 (21%) 100 (25%) 1-4 days 151 (74%) 272 (69%) 5 days 3 (2%) 13 (3%) 6 days 6 (3%) 12 (3%) Max number of <0.001 diarrhea episodes in 24 hours 1-3 episodes 30 (15%) 89 (22%) 4-5 episodes 89 (44%) 228 (57%) 6 episodes 84 (41%) 80 (20%)

16 Clinical characteristics of enrolled children Rotavirus Positive Rotavirus Negative n=203 (%) n=397 (%) p-value History of fever (% 162 (80%) 277 (70%) 0.01 yes) Vesikari Score (mild) 138 (68%) 303 (76%) (moderate) 64 (32%) 91 (23%) 15 (severe) 1 (1%) 3 (1%) Median Vesikari 10 (6-15) 9 (4-17) <0.001 Score (range) Child received any 0.10 vaccine Yes 157 (77%) 329 (83%)

17 Children s age at RV vaccination, by RV results

18 RV vaccine effectiveness among children RV vaccine doses 8 months who were ever vaccinated Rotavirus positive n (%) Rotavirus negative n (%) Unadjusted VE (95% CI) Adjusted VE* (95% CI) n=118 n=221 0 doses 29 (25%) 25 (11%) ref ref 1 dose 11 (9%) 19 (9%) 50% (-25%, 80%) 40% (-66%, 78%) 2 doses 78 (66%) 177 (80%) 62% (31%, 79%) 62% (26%, 80%) Any dose 89 (75%) 196 (89%) 61% (29%, 78%) 60% (24%, 79%) *Adjusted for month/year of birth, month/year admission, and district where child lives

19 Summary The monovalent RV vaccine had a 60% effectiveness against RV diarrhea in the Philippines Supports an earlier analysis showing a decline in diarrheal hospitalizations and diarrheal consultations in the whole province Results have been presented to the Philippines Department of Health in support of expanding use of the RV vaccine

20 Acknowledgemen ts WHO Regional Office for the Western Pacific Region US Centers for Disease Control and Prevention DOH-Expanded Programme for Immunization (EPI) DOH-Epidemiology Bureau Research Institute for Tropical Medicine Province of Agusan Del Sur DO Plaza Memorial Hospital CARAGA Region EPI CARAGA Regional Surveillance Unit

21 Thank you!