This interview was originally published in the Dengue Vaccine Initiative Newsletter.

Dr. Sazaly Abu Bakar is a professor and the Director at the Tropical Infectious Diseases Research and Education Center (TIDREC) and WHO Collaborating Center for Arbovirus Research and Reference (Dengue Fever and Severe Dengue) at University of Malaya in Kuala Lumpur, Malaysia. He received his PhD and post-doctoral training in virology at the University of Texas Medical Branch, Galveston, Texas, USA.

Dr. Sazaly has been involved with dengue research for over 20 years and has also maintained strong research interest in emerging infectious diseases. His interest in dengue, in particular, is rooted in its knowledge gaps: “it is a fascinating disease needing a lot more research to take on.” In an interview with DVI, Dr. Sazaly shares more on his views of dengue prevention and control and needs in the dengue research field.

How would you describe the progress, or step backs, in global dengue prevention and control in recent years?

Dengue stakeholders and researchers are making tremendous progress in our understanding of the disease especially when it comes to the virus itself.  We know the variables that contribute towards the global spread of the disease. 

But, while we have developed various modalities to eliminate, eradicate or reduce the vector, Aedes aegypti, we are still lacking effective dengue management at its source: viremic humans. We need newer tools to detect dengue. These tools are particularly urgent to determine impending severe dengue, which can lead to mortality, making it the greatest danger of being infected with dengue fever.

What would you identify as the current biggest knowledge gaps in the dengue research field that can slow down global dengue prevention and control? 

I would identify, on one hand, understanding the potential contribution of asymptomatic viremic individuals in sustaining the presence of the virus in a population. On the other hand, I think we need to better understand long term immunity and/or the role of herd immunity.

What more can international, regional and multilateral organizations do to help control and prevent dengue?

They could de-emphasize mosquitoes as the root cause of dengue and shift focus to humans. Also, better diagnosis of early dengue and making rapid tests affordable and accessible, especially to the economically marginalized population in dengue endemic regions, are crucial to preventing and controlling this disease. These are areas where more can be done.

How can countries and their ministries of health better communicate about dengue to prevent cases and control the disease’s spread?

Countries should focus on education to increase awareness of dengue as a disease that requires a human host to continue its cycle. In other words, mosquitoes are just a vector for the virus, without viremic individuals to feed on dengue, dengue’s spread will stop.

What are your views on dengue vaccines, particularly the CYD-TDV candidate? What questions should countries prioritize when/if considering vaccine introduction?

I think we are seeing a commendable initial effort to develop vaccines against dengue.

Countries should prioritize questions on three topics: (1) safety and efficacy, (2) long-term effectiveness and (3) cost-benefit over other intervention modalities.

What factors in vaccine introduction should countries not yet considering adopting dengue vaccines look into to learn from others’ that do introduce vaccines once available?

I think they should consider the same three topics and if there is a need, they should consider which population to vaccinate as well as the 'acceptable' level of presence of the infection in the population.


Photo: Dr. Sazaly Abu Bakar holds mosquito-repelling coils. Credit: Kosmo