Dengue is one of the country’s most pressing public health issues. Recent figures from the Department of Health noted an 11.5 percent increase in reported cases of dengue from January to September last year compared to the same period this year. The total number of dengue infections was pegged at 142,247 in 2016 against the 127,525 in 2015.

The introduction of Dengvaxia, the dengue vaccine developed by pharmaceutical organization Sanofi Pasteur, is thus a most welcome development. Dengue has not only wreaked physical, emotional, and psychological havoc among families who have had to deal with the disease, it also comes at an enormous financial cost. In the Philippines, it is estimated that the economic burden of the disease comes to about $345 million a year.

In a recent briefing, medical professionals from Sanofi Pasteur, namely Alain Bouckenooghe, Associate VP and Regional Head of Clinical R&D, and Joshua Nealson, Head of Epidemiology and HEOR Asia and JPAC Region, cleared several points about Dengvaxia.

Here’s what you need to know about the dengue vaccine.

#1 The vaccine was not developed overnight. Sanofi Pasteur worked on the vaccine for some 20 years. The organization has been involved in dengue vaccine research since 1994. Development of the vaccine was challenging because dengue is not caused by one but four distinct virus types. This means that an effective vaccine must provide protection against all four dengue viruses.

#2 The dengue vaccine is indicated for use by persons nine to 45 years old living in endemic settings. The vaccine will be given in three doses every six months as the body needs time to maximize its efficacy. At the moment, the dengue vaccine is not recommended for children below nine years of age as they would not get enough benefits from it. However, Sanofi Pasteur hopes to include younger kids in the future.

#3 Based on a clinical study program involving 40,000 children, adolescents, and adults in 25 studies in 15 countries around the world, the dengue vaccine is effective in several aspects.

There was a 65.6 percent reduction in symptomatic dengue caused by any of the four serotypes of the virus among subjects 9 to 16 years old over the 25-month surveillance period. There was also an 80.8 percent reduction in hospitalized dengue and a 93.2 percent reduction in severe dengue in the same age group.

#4 The vaccine is effective against all four serotypes of dengue. Its overall efficacy is based on proven clinical efficacy against all four serotypes which were circulating during the Phase III studies.

#5 While Dengue and Zika are closely related virus types, the dengue vaccine is not effective against Zika. However, Sanofi Pasteur does have an action program for Zika.

#6 The dengue vaccine is now available in 13 countries: Brazil, Philippines, Mexico, El Salvador, Paraguay, Singapore, Costa Rica, Guatemala, Peru, Indonesia, Thailand,  Bolivia, and Cambodia. The vaccine becomes available in a specific country following its approval of said country. Sanofi Pasteur is working at having the vaccine approved in other countries where dengue is endemic.

#7 No significant adverse reactions have been observed on subjects nine to 60 years of age.