by Dr T. Anh Wartel
Regional Medical Expert for Dengue in Asia Pacific at Sanofi Pasteur
No one was prepared for the Ebola outbreak in 2014 and the consequences were manifold.
Besides the long-term impact of the deadly virus on the economy and the community, response to the epidemic also disrupted the provision of healthcare services overall, causing setbacks in the treatment and control of other infectious diseases such as HIV, tuberculosis and malaria. [1,2]
Likewise, the world has witnessed the significant repercussions of Zika more recently, particularly the visible birth defect of microcephaly in babies whose mothers were infected with the virus during pregnancy. The World Health Organisation (WHO) declared a Public Health Emergency of International Concern in response to the Zika virus early last year. 
These scenarios might have been different had we been equipped with a suitable and effective tool against Ebola and Zika, such as a vaccine, as well as a proper process to introduce it, i.e. a vaccination programme.
As we look to preventing similar health crises in the future, we need to remember that epidemics and outbreaks in particular happen very quickly – anywhere and without warning. After all, viruses and infectious diseases are not like human beings; they do not respect borders.
With increased urbanisation, mobility of populations and climate change, Asia has never been more vulnerable to the spread of fast growing diseases such as dengue. In the past five decades, we have seen a 30-fold increase in the spread of dengue to over 128 countries. [4,5] Asia alone bears 70% of the disease burden. Home to 600 million people, dengue is estimated to impose a hefty sum of USD949 million annually on the ASEAN region. 
Vaccines are one of the most important and cost-effective tools of prevention that often get side-lined by the greater preoccupation with an ultimate cure for any disease. Vaccination has demonstrated its unique ability to confer protection to entire populations when vaccination coverage reaches a threshold. With a vaccine, we would be able to take a proactive and precautionary measure against infectious diseases, and avoid another epidemic such as Ebola.
Last year, WHO issued its recommendation that countries with high dengue burdens consider introduction of the world’s first dengue vaccine to help better control the disease.  Since then, the dengue vaccine has been approved for prevention of dengue in 18 countries worldwide with geographic regions that have high dengue burdens. In Southeast Asia, this includes Singapore, the Philippines, Thailand and Indonesia where vaccination is being implemented once licensed.
Developing the world’s first dengue vaccine and bringing it first to the endemic countries in Southeast Asia was a joint effort and accomplishment within the scientific and regulatory community. The next challenge for us now is conveying the value of vaccination to the public community. This means finding effective ways of translating complex disease knowledge, complex data, and technical information into layman terms that people would be able to understand, and therefore be convinced to get vaccinated.
Public immunisation programmes that are aligned with the WHO’s recommendation are currently underway in the Philippines and the Parana State of Brazil. Used as part of an integrated dengue prevention effort together with vector-control, these programmes have the greatest potential to contribute to significant disease burden reduction. The Philippines was the first country to initiate this, with nearly 500,000 school-children vaccinated with first dose when the programme began in April 2016. In June 2017, Cebu commenced vaccinating towards a community-based programme at designated health centres.
While it is heartening to see game-changing progress made in dengue management in endemic areas, we need to continue identifying localised gaps in the diverse communities across the region. Dengue is a disease that can affect anyone regardless of age, gender, underlying health, occupation or socioeconomic status. 
Everyone has a part to play in ensuring a safe, public health environment for all. The ASEAN community must stay committed in fighting against the dengue virus and work towards an integrated approach including disease management programme – social education and community engagement about the disease, vector control strategies, and vaccination.
- Alyssa S. Parpia M, Martial L. Ndeffo-Mbah P, Natasha S. Wenzel M et al. Effects of Response to 2014–2015 Ebola Outbreak on Deaths from Malaria, HIV/AIDS, and Tuberculosis, West Africa. Emerging Infectious Diseases. 2016;22(3)
- Elston JWT, Cartwright C, Ndumbi P et al. The health impact of the 2014-2015 Ebola outbreak. Public Health. 2017;143:60-70.
- World Health Organisation (WHO). WHO statement on the first meeting of the International Health Regulations (2005) (IHR 2005) Emergency Committee on Zika virus and observed increase in neurological disorders and neonatal malformations. Available at: https://www.who.int/mediacentre/news/statements/2016/1st-emergency-committee-zika/en/ . Accessed 23 June, 2017.
- World Health Organisation (WHO). Fact sheet: Dengue and severe dengue. Available at: https://www.who.int/mediacentre/factsheets/fs117/en/. Accessed 3 March, 2017.
- World Health Organisation (WHO). Dengue Guidelines for diagnosis, treatment, prevention and control 2009. Available at: https://www.who.int/tdr/publications/documents/dengue-diagnosis.pdf. Accessed 3 March, 2017.
- Shepard DS, Undurraga EA, Halasa YA et al. The global economic burden of dengue: a systematic analysis. The Lancet Infectious Diseases. 2016;16(8):935-941.
- World Health Organisation (WHO). Dengue vaccine: WHO Position Paper – July 2016. Available at: https://www.who.int/wer/2016/wer9130.pdf?ua=1. Accessed 7 April, 2017.
- Development PCfHRa. Dengue vaccine research and development. 2017. Available at: https://www.pchrd.dost.gov.ph/index.php/news/library-health-news/3787-dengue-vaccine-research-and-development. Accessed 7 April, 2017.
About the Author
Dr T. Anh Wartel
Regional Medical Expert, Dengue Asia Pacific
Dr Wartel brings close to two decades of experience in epidemiological and clinical research to her current role as regional medical director for dengue in Asia Pacific at Sanofi Pasteur.
Her key responsibilities are equipping the Asia market for the registration and delivery of the world’s first tetravalent dengue vaccine (CYD-TDV) through close discussions with health authorities and regulatory agencies, and by sharing her expert knowledge with health care professionals and multiple stakeholders.
Dr Wartel was also involved in over 13 years of research into the development of the dengue vaccine, which included leading an epidemiological cohort study on dengue in Vietnam to better understand its burden; conducting early stage vaccine trials across Asia Pacific; providing strategic and scientific input to clinical development plans; overseeing all phases of studies for the dengue vaccine; and managing CTD development and multiple scientific and technical meetings with National Regulatory Agencies, Ministry of Health and Health Authorities.
Prior to joining Sanofi Pasteur in 2004, Dr Wartel commenced her career in clinical research at the French National Agency of Research on HIV-AIDS (ANRS), as the co-investigator for phase III-IV drug and vaccine studies in HIV-infected patients in a University Hospital in Paris.
Dr Wartel has delivered several scientific lectures and presentations to international and regional audiences on infectious diseases and vaccination. She earned her MD Diploma from Paris XII Medical School (1999), with subsequent specializations in HIV Disease in Urban Medical Practice (1999), Emergency in Pediatrics (2001) and Tropical Medicine (2005).