New dengue vaccine approved by WHO as 6.7 million cases reported in Americas

New dengue vaccine approved by WHO as 6.7 million cases reported in Americas

A new vaccine against dengue has been approved by the World Health Organization (WHO) as over 6 million cases of the mosquito-borne virus have been reported in the Americas so far this year.

Dengue is transmitted to humans through the bite of an infected mosquito. It can cause flu-like symptoms and in rare cases lead to death.

The vaccine was developed by Japanese pharmaceutical company Takeda and contains weakened versions of the four serotypes of dengue virus.

The global health agency recommended the vaccine for children aged six to 16 years old in areas where there are high levels of the virus. Two doses of the jab are given three months apart.

Dr Rogerio Gaspar, WHO's Director for Regulation and Prequalification, said the approval "is an important step in the expansion of global access to dengue vaccines".

"With only two dengue vaccines to date prequalified [approved], we look forward to more vaccine developers coming forward for assessment, so that we can ensure vaccines reach all communities who need it," Gaspar added in a statement.

84% efficacy against dengue

The European Medicines Agency (EMA) approved Takeda's vaccine in 2022. A study found that the vaccine was 84 per cent effective at preventing hospitalisation.

The vaccine was approved by WHO in 2020 but is not being widely used because it requires screening for previous dengue infection, the agency said.

WHO estimates that there are more than 100 to 400 million cases of dengue each year.

Last week, the agency's regional office in the Americas said that there were 6.7 million cases of dengue reported in the region in 2024, representing an increase of 206 per cent compared to the same period in 2023.

The European Centre for Disease Prevention and Control (ECDC) warned last year that the mosquito species that is a known vector of dengue and other viruses has spread in Europe amid warming temperatures.

This is likely to lead to more cases and deaths due to mosquito-borne illnesses such as dengue. In 2023, France, Italy, and Spain all reported locally-acquired dengue cases.