The number of reported Dengue cases in Malaysia grew 13 percent to 12,518 in the first seven months of the year from the same period last year, putting the country on alert as the government called the disease a "serious threat".

The disease killed 25 people in the period, compared with 19 reported last year.

"We are very concerned over this development," Health director-general Hasan Abdul Rahman told reporters on Tuesday.

Last month, a Malaysian prince promoted a protein pill that starves mosquito larvae that could revolutionise the global fight against dengue.

Dengue, a disease transmitted to humans by Aedes mosquito, kills about 20,000 people worldwide every year according to the World Health Organisation.

The mosquitoes breed easily in Malaysia due to its hot and humid climate.