A case-control study to determine the effectiveness of a tetravalent dengue vaccine in the state of Paraná, Brazil

José Cássio de Moraes; Irina Nastassja Riediger; Fernanda Crosewski; Denise Oliveira Garrett; Francieli Fontana Fantinato; Karina Braga Ribeiro; Expedito José de Albuquerque Luna

doi:10.1016/j.lana.2021.100141

A case-control study to determine the effectiveness of a tetravalent dengue vaccine in the state of Paraná, Brazil

Lancet Reg Health Am. 2021 Dec 20:7:100141. doi: 10.1016/j.lana.2021.100141. eCollection 2022 Mar.

Authors

José Cássio de Moraes¹, Irina Nastassja Riediger², Fernanda Crosewski³, Denise Oliveira Garrett⁴, Francieli Fontana Fantinato⁵, Karina Braga Ribeiro¹, Expedito José de Albuquerque Luna⁶

Affiliations

¹ Faculdade de Ciências Médicas da Santa Casa de São Paulo, São Paulo, Brazil.
² Laboratório Central do Estado do Paraná, Secretaria Estadual de Saúde, São José dos Pinhais, Brazil.
³ Secretaria Estadual de Saúde do Paraná, Curitiba, Brazil.
⁴ Sabin Vaccine Institute, WA, USA.
⁵ Ministério da Saúde, Brasília, Brazil.
⁶ Faculdade de Medicina, Universidade de São Paulo, Av. Dr. Enéas de Carvalho Aguiar 470, São Paulo 05403-000, Brazil.

Abstract

Background: The Brazilian state of Paraná conducted a mass vaccination campaign against dengue with the tetravalent attenuated vaccine CYD-TDV. The campaign targeted thirty endemic municipalities. The objective of this study was to assess the effectiveness of CYD-TDV in preventing symptomatic virologically confirmed dengue cases according to specific age groups in five of the municipalities.

Methods: A case-control study was carried out in the five most populous municipalities targeted by the vaccination, with a vaccine uptake of 25%. Symptomatic dengue cases were identified by the municipal health departments. The age groups targeted were 15-18 and 19-27 in four municipalities and 9-14 and 28-44 in one municipality. All cases were confirmed by real time reverse transcription quantitative polymerase chain reaction (RT-qPCR). For each case, two controls were selected: a neighbourhood control and a workplace or school/college control, matched by age group. A conditional logistic regression model was used to determine the odds ratio for vaccination and the vaccine effectiveness.

Findings: Study participants included 618 RT-qPCR-confirmed dengue cases and 1,236 matched controls (with a non-reactive dengue IgM serologic test). Vaccine effectiveness against dengue due to any serotype was 11·1% (95% CI: -19·0%; 33·6%). Effectiveness against DENV-1 was 33·3% (95% CI: -5·0%; 57·6%) and against DENV-2 was -56·7% (95% CI: -142·2%; -5·0%). No DENV-3 was detected. The vaccine was significantly effective in the prevention of DENV-4 cases (VE = 93·3%; 95% CI: 47·7%; 99·2%).

Interpretation: CYD-TDV was effective in the prevention of symptomatic cases due to DENV-4, but not due to any serotype. The low dengue seroprevalence in the target population could possibly be related to these results.

Funding: This study was supported through a grant to the Sabin Vaccine Institute from Sanofi-Pasteur. Sanofi-Pasteur had no role in the study design, protocol development, data collection, analysis, or publication of results.

Keywords: Brazil; CYD-TDV; Paraná; dengue; vaccine effectiveness.