At least 45 people have died and 30,000 have been forced from their homes in Bolivia due to heavy rains and flooding produced by the climatic phenomenon known as La Niña, according to officials.
After downpours and floods associated with the El Niño ocean-atmosphere phenomenon left 56 dead, affected 600,000 people and caused economic losses totalling $443 million between January and March of 2007, La Niña is taking its toll this year on Bolivia, South America's poorest nation.
Rain has not stopped falling in several regions of Bolivia since the start of 2008, resulting in serious flooding and causing rivers to overflow their banks, the Spanish news agency EFE said.
The provinces of Cochabamba, Chuquisaca, Santa Cruz and La Paz, where a combined total of 40 people have died, have been the hardest hit not only by flooding but also diseases such as dengue, hantavirus and leptospirosis.
Dengue is the main problem in the central province of Cochabamba, where 109 of the 147 cases nationwide have occurred, health ministry said.
That disease is transmitted by the Aedes aegypti mosquito, which is most commonly found in tropical areas and especially multiplies during the rainy season.
Farmers of Santa Cruz, Bolivia's wealthiest province, said they have suffered some $300 million in crop losses since November because of the rains and flooding.
International aid has begun arriving and, for the past several days, Brazilian, Chilean and Venezuelan helicopters have evacuated people from affected areas.
Peru, Argentina and the US have donated several tonnes of humanitarian aid and the UN World Food Program already is attending to more than 7,400 families.