BRAZIL (REUTERS) - Brazil is pushing ahead with efforts to develop a vaccine for dengue fever.

Officials on Monday (Feb 22) signed off on the third phase of clinical trials for the vaccine.

Dengue is transmitted by the same mosquito that transmits chikungunya and Zika.

President Dilma Rousseff says until a vaccine is available the public must help in the fight.

"We still do not have a vaccine," she says, adding that ensuring that no more people are infected "will only come about through the process of eliminating mosquito breeding grounds in water."

The government is investing US$75 million (S$105 million) dollars in the dengue vaccine effort.

Earlier this month it also signed an agreement with the US Centers for Disease Control to develop a vaccine against Zika.