Session:

Vaccines & Vaccine Development

Abstract No.:

48.015

Title:

Efficacy of mumps vaccine in Korea

Author(s):

H. W. Kim¹, H. K. Cho¹, K. M. Choi², B. W. Eun³, S. Y. Lee⁴, K. H. Kim¹; ¹Ewha Womans University School of Medicine, Department of Pediatrics and Center for Vaccine Evaluation and Study, Ewha Medical Research Institute, Seoul/KR, ²Kwandong University College of Medicine, Department of Pediatrics, Goyang/KR, ³Gacheon Medical school, pediatrics, Incheon/KR, ⁴The catholic university of Korea, Pediatrics, Incheon/KR

Abstract:

Background: Although mumps is a vaccine-preventable disease and mumps vaccine has more than 95% of its vaccination rate as a component of MMR vaccine, disease occurrence is continued. We aimed to assess the effectiveness of the mumps component of the MMR vaccine.
Methods: This study evaluated the efficacy of mumps vaccine through the prospective and retrospective case-control studies in four university hospitals. Another achievement is to establish the mumps virus RT-PCR assays for diagnosis in the research team.
Results: In prospective case-control study, 55 cases of mumps were identified and 165 controls were selected from March 2010 to October 2011. Data about their demographic characteristics and MMR vaccination status were collected in cases and controls. Risk for disease estimated by conditional logistic analysis is OR 0.67 (95%CI 0.06-7.35) in vaccinated that is lower than in nonvaccinated. Risk for mumps is OR 0.58 (95%CI 0.05-6.90) for 1 dose and OR 1.10 (95% CI 0.09-13.31) for 2 doses. In retrospective studies, 122 cases of mumps were identified and 449 controls were selected. In 2008-2009 in western Seoul, Incheon and Goyang, an outbreak of mumps occurred among children most of whom were born before 1994. 98% of cases whose vaccination status were available had a history at least one MMR vaccination. Estimated risk for disease is OR 0.33 (95% CI 0.02-5.33) in vaccinated that is lower than in nonvaccinated. Risk for mumps is OR 0.33 (95% CI 0.02-5.33) for 1 dose and OR 0.11 (95% CI 0.01-2.12) for 2 doses. And, we analyzed data collected in the prospective and retrospective study. Estimated risk for disease is OR 0.50 (95% CI 0.08-2.99) in vaccinated that is lower than in nonvaccinated. Risk for mumps is OR 0.58 (95% CI 0.10-3.56) for 1 dose and OR 0.42 (95% CI 0.06-2.81) for 2 doses.
Conclusion: Mumps vaccine had preventive effect and two dose vaccination had superior effect than one dose, even though there was no statistically significant difference. In addition to the efficacy of the vaccine, it is needed to consider other factors that are involved in occurrence of mumps outbreak.