Mexico Becomes the First Country to Greenlight a Vaccine for Dengue Fever

The mosquito-borne virus infects an estimated 400 million people a year concentrated in Asia, Africa and Latin America, with around 12,500 cases ending in the death of the patient.
December 9, 2015, 11:20pm
Imagen por Denis Pamlin vía Flickr

Mexico has become the first country in the world to approve the use of a newly developed vaccine against the virus that causes dengue fever across large swathes of Asia, Africa and Latin America.

The Mexican health ministry said it had approved the vaccine after confirming its "quality, safety, and therapeutic effectiveness in a global protocol."

According to the World Health Organization, the dengue virus infects an estimated 400 million people around the world every year, with 12,500 of these cases ending in the death of the patient. Typically sufferers make a full recovery after a bout of high fever, along with severe muscle and joint pain.

The vaccine, called Dengvaxi, was developed by the French pharmaceutical company Sanofi. The company said that clinical trials involving 40,000 people in 15 countries indicated it was about 60 percent effective in preventing four strains of the virus. It was much more effective when the patient had already been infected by one of the strains. The company has not released any details of how much it intends to charge.

Mexico is one of 20 countries in Latin America and Asia where Sanofi is currently seeking regulatory approval for use of the vaccine.

Related: Nearly a Million Brazilians Contracted Dengue Fever Already This Year

A statement from the ministry said there were 32,100 cases of dengue in Mexico last year, with 8,668 severe enough to require hospitalization. It added that dengue-related expenditure eats up 2.5 percent of its budget.

The ministry said the vaccine could now be used to try and protect people in areas where the virus is endemic between the ages of nine and 45. The trials showed the vaccine provided little protection for younger children and older adults.

Public policy on dengue prevention in Mexico up until now has focused on efforts to get families to reduce accumulations of stagnant water where mosquitos breed and limit exposure at night with the help of nets. The Mexican authorities have yet to decide whether to include the vaccine in state-sponsored vaccination programs where people can get the shots for free.

"The importance of this vaccine lies in the fact that it is the first with proven efficacy in preventing this illness," said pediatric infectologist María del Carmen Gorbea Robles, who added she expected it to make an important dent in the number of cases. "It is a great achievement though, as an infectologist, I think we should be conservative in our expectations."

Related: Are Mosquitoes Behind an Increase in Brazilian Babies Born with Abnormally Small Heads?

Follow Nathaniel Janowitz on Twitter: @ngjanowitz