The Amazon region of Bolivia has been undergoing a spread of Dengue fever, with more than 550 cases reported in the past four weeks, the Bolivian Health Ministry said Saturday.

The spread was especially rapid in the two eastern provinces of Pando and El Bani, according to sources in the Bolivian capital La Paz.

About 450 cases and 100 cases were found in Pando and El Bani respectively in the past four weeks, among which four were the deadly hemorrhagic type, the ministry said in a report.

Recent heavy rainfalls and floods in the Amazon region created perfect breeding grounds for mosquitoes and caused the disease to spread. There were 1,400 cases reported in Bolivia last year, the report said.

Bolivia has taken measures to enhance health and epidemic prevention efforts in the flood-hit areas in an effort to stop the spread of the disease.

Dengue fever is a painful, debilitating disease transmitted by mosquitoes. Also known as "breakbone fever," dengue fever's symptoms include high temperatures and muscle aches.

There are an estimated 50 to 100 million cases of dengue fever annually around the world and approximately 25,000 deaths.