According to an agreement signed by Cuban and Chinese officials in Beijing, China will finance the project and produce larvicide in the country. It will also sell Cuba 6 million doses and donate a further 500,000 doses to the island's government,

Peng Xin, deputy director of the Biological Products Laboratory Company (Labiofam), told reporters in China that it was a good start for the two nation's joint plans.

Bactivec is a 20 year-old formula that contains crystals from the bacteria Bacillus Thuringiensis's, which is deadly for Aedes Aegypti, the mosquito that carries Dengue fever.

Strong demand for Bactivec, which has long been produced on a smaller scale in Cuba, has triggered a search for higher-volume production.

The larvicide is not toxic for humans. It has no smell or color, and can be added to drinking water without risking human health.

Labiofam produces and sells pharmaceutical, food and hygiene products which have been patented in 20 nations across Latin America, the Caribbean, Asia and the Middle East.

Dengue is caused by four closely related viruses and is spread by the Aedes Aegypti mosquito, which breeds in still water. Its symptoms include high fever, nausea, rashes, backache and headache.

Most mainstream dengue cases are not fatal, but the hemorrhagic variant, which causes severe internal bleeding as blood vessels collapse, can kill up to 20 percent of its patients.