The health ministry is embarking on another seasonal campaign to reduce the number of dengue-carrying mosquitoes.
The first part of the campaign targets discarded vehicle tires, which make great locations for breeding mosquitoes.
The Aedes aegypti mosquito is opportunistic and can seek out small puddles of water for its egg-laying. The areas with the most cases usually are the coastal areas, which is why the latest campaign began in Limón.
Each year thousands of Costa Ricans are sickened by dengue.
The disease, if contracted a second time, could be life-threatening.
Daisy Corrales Díaz, the health minster, urged homeowners and business people to make sure their areas are free of breeding spots.
Costa Rican law requires retailers of tires to accept used ones for recycling, but many motorists just throw the tires away.
The major tire companies are helping with the campaign. There also will be advertising to encourage citizens to stamp out dengue. The program will cover all of the country in sections on various dates through August.