The dengue inspectors
16 April 2015 Last updated at 13:40 BST
Sao Paulo is currently experiencing a severe water shortage.
Across the city many people are storing water in their homes out of fear that they will be cut off with little warning.
But the buckets and pots of water have created a hidden menace - they are creating breeding grounds for mosquitoes that carry dengue fever.
Luis Barrucho went to see a team of health officials - the dengue inspectors - who are working to tackle this problem.
Brazil: Fighting dengue fever in Sao Paulo
19 April 2015 Last updated at 01:26 BST
One-hundred-and-thirty people have died in an outbreak of dengue fever in Sao Paulo.
More than 460,000 cases have been reported so far this year.
The disease is spread by mosquitoes and the epidemic is blamed on wet weather, and on storing contaminated water - at a time of water shortages across the country.
Peter Dobbie reports.