About the Dengue Vaccine

I read a NEJM article that says Sanofi Pasteur finished the phase 3 trial of their dengue vaccine.

Last year , in Tokyo , a dengue fever outbreak occurred and Yoyogi park was cordoned off for the operation that extinguish suspected vector mosquitoes . I saw  news footage in which men in coats and masks were splaying insecticide into the bushes in Yoyogi  park on TV.

According to medical websites(CDC and WHO) or textbooks ,most of the Dengue fever patients have good medical course. In general , a majority of dengue fever patients recover without sequelae.

Rare patients develop into lethal condition(severe dengue or dengue hemorrhagic fever) , but as long as appropriate treatment is conducted , they seldom die. The fatality rate is below 1 percent.

'We don't have to fear dengue fever so much ' , I thought, but situations are different  in developing countries or from the viewpoint of global health issue. World Health Organization reported that 500.000 patients develop dengue hemorrhagic fever (severe condition in dengue fever)and  22.000 patients die per a year in the world.

I read
'Efficacy of Tetravalent Dengue Vaccine in Children in Latin America.' (NEJM 8th January 2015).

The gist is ...

They enrolled children who were between 9 and 16 years old in Colombia , Brazil , Mexico , Puerto Rico and Honduras.
They administered their dengue vaccines to 13920 children(at 0,6,12 months).
They administered placebos to 6949 children.

[The result]
The number of developing dengue fever:
Vaccine group is 277(after 1st injection) or 176(after 3rd injection).  
Placebo group is 385(after 1st injection) or 221(after 3rd injection).
The vaccine efficacy after 1st injection is 64.7% (95% CI , 58.7 to 69.8)

The number of developing severe dengue:
Vaccine group is 1.
Placebo group is 11.
The vaccine efficacy after 1st injection is 91.7%(95% , 31.4 to 99.8).

The number of developing dengue hemorrahagic fever:
Vaccine group is 1.
Placebo group is 10.
The vaccine efficacy after 1st injection is 91.7%(90.0% , 10.7 to 99.8).

From this result , I think this vaccine is very promising.
The vaccine efficacy of severe dengue and dengue hemmorrhagic fever is outstanding.

After this vaccine is approved and incorporated into the vaccination policy of dozens of countries , great number of children will be able to avoid their death.  

Many mosquitoes will be able to avoid their death , too.  
According to CDC and WHO web pages , the only way to prevent dengue fever now is 'vector control':killing mosquitoes.