Global warming could expose as many as a billion people to mosquito-borne diseases including dengue and Zika by 2080, says a new study that examined temperature changes on a monthly basis worldwide.

The study found that with the rise in temperature, dengue is expected to have a year-round transmission in the tropics and seasonal risks almost everywhere else. A greater intensity of infections is also predicted.

To understand, researchers from Georgetown University in the US looked at temperatures month by month to project the risks through 2050 and 2080.

On the other hand, in areas with the worst climate increase, including west Africa and southeast Asia, serious reductions are expected for the Aedes albopictus mosquito, most noticeably in southeast Asia and west Africa, revealed the study, published in the journal PLOS Neglected Tropical Diseases.

Both Aedes aegypti and Aedes albopictus mosquitoes can carry dengue, chikunguyna and Zika viruses, as well as at least a dozen other emerging diseases.

Dengue is the fastest growing mosquito-borne disease across the world today, causing nearly 400 million infections every year, according to the World Health Organisation (WHO).

The 2018 data from the National Vector Borne Disease Control Programme (NVBDCP) and National Health Profile showed that cases of dengue increased 300 per cent - from less than 60,000 cases in 2009, it increased to 188,401 in 2017.