Dengue Vaccine Screening: Is It Necessary?
- Dengvaxia, a dengue vaccine developed by sanofi Pasteur, was initially licensed in Mexico in December 2015.
- This phenomenon is linked to antibody-dependent enhancement, or ADE.
- If a person contracts dengue a second time with a different serotype, ADE can occur.
Is dengue vaccine screening necessary? The WHO recommends it, but why? News Directory 3 breaks down the critical need for pre-vaccination checks for Dengvaxia, the first licensed dengue vaccine. This vaccine, approved in 20 countries, poses a risk for those never infected. Learn about antibody-dependent enhancement (ADE), the potential for severe dengue, and the importance of identifying prior infections before vaccination. Discover how rapid diagnostic tests (RDTs) could revolutionize the screening process. What’s next in the fight against dengue?
Dengue Vaccine and Antibody-Dependent Enhancement: What You Need to Know
Updated may 30, 2025
Dengvaxia, a dengue vaccine developed by sanofi Pasteur, was initially licensed in Mexico in December 2015. The World Health Organization reports it is now approved for use in 20 countries for individuals aged 9 to 45 living in areas where dengue is common. However, while the vaccine is considered safe for those with prior dengue infection, it may increase the risk of severe dengue in individuals who have never been infected.
This phenomenon is linked to antibody-dependent enhancement, or ADE. The dengue virus has four serotypes, all capable of causing illness. A first-time dengue infection results in long-lasting antibodies specific to that serotype, along with short-term antibodies offering broader protection.Once the latter wane, protection remains only against the initial serotype.
If a person contracts dengue a second time with a different serotype, ADE can occur. in such cases, pre-existing antibodies fail to neutralize the new virus. Instead, scientists believe these antibodies bind to the virus, facilitating its entry and infection of cells.This can transform what might have been a mild infection into a severe one. Therefore, contracting different dengue serotypes sequentially can lead to more severe outcomes.
Ideally, a dengue vaccination program should stimulate the body to produce antibodies capable of neutralizing all four dengue serotypes, thus preventing ADE. Though, research suggests that Dengvaxia may primarily induce antibodies against only one serotype, DENV-4, in individuals without prior dengue exposure.
The WHO advises pre-vaccination screening to ensure the vaccine is administered only to individuals previously infected with dengue.The organization notes that implementing such a strategy requires careful assessment and that vaccination should be part of a comprehensive dengue prevention and control plan.
While laboratory tests offer the most accurate screening method, they can be time-consuming and resource-intensive. Researchers suggest potential delays of several days between sample collection and result delivery. This could hinder individuals unable to attend multiple clinic visits from receiving necesary protection.
Rapid diagnostic tests (RDTs), though less precise than lab tests, could enable faster screening in dengue-endemic areas with limited resources. These tests could also benefit areas with high transmission rates, allowing for immediate vaccination. Though, RDTs typically detect current, not past, infections. Further research may be needed to modify or develop new RDTs suitable for dengue pre-vaccination screening.
What’s next
Further research is needed to refine dengue pre-vaccination screening methods and improve the safety and effectiveness of dengue vaccination programs worldwide.