Dengue fever is a major public health issue. More than 3.6 billion people are at risk of being infected with dengue virus (DENV) and about 390 million infections occur each year in more than 120 tropical and subtropical countries. The development of dengue vaccines is an important breakthrough for public health.
The workshop was organized in response to SAGE’s recommendations on the use of the first licensed vaccine (CYD-TDV/Dengvaxia®) and the implementation of a strategy for screening individuals before vaccination. Indeed, a retrospective analysis of clinical trials revealed that the performance of the vaccine varied according to the serological status of the recipient. The findings showed an excessive risk of severe dengue fever in seronegative subjects, while in seropositive subjects, the vaccine was effective and safe. To support a pre-vaccination screening strategy whereby only seropositive individuals would be vaccinated, the World Health Organization and many expert groups have highlighted the urgent need for rapid diagnostic tests (RDTs) to determine the patient’s serological status.
The objective of the workshop was to evaluate rapid diagnostic tests for screening for past dengue infection, including sensitivity and specificity thresholds for tests acceptable to decision-makers and communities. It also discussed strategies for implementing pre-vaccine screening programs for dengue vaccines.
The meeting was supported by Sanofi Pasteur, bioMérieux and Chembio with the participation of the NGO FIND. Organized into thematic and regional workshops, it brought together experts from national immunization programs, academia, and policy-makers with experience in vaccine introduction, in addition to diagnostic manufacturers and laboratory network managers.
Participants were able to exchange perspectives and approaches on how to implement pre-vaccination screening strategies in their countries of origin. Scenarios with different RDT performance were discussed in the context of population benefit versus individual risk of vaccines. Communicating on the risks of dengue vaccination while bolstering the confidence of recipients in the same vaccine was a main topic during these two days. At the end of the meeting, the project of a petition for a World Dengue Day was discussed.
A full report on this workshop is available on the PDC website.