Presidential candidate Dilma Rousseff (center) campaigns in Belo Horizonte, Brazil, alongside outgoing President Luiz Inacio Lula da Silva. Pedro Vilela/AFP/Getty Images hide caption

itoggle caption Pedro Vilela/AFP/Getty Images

A bladder at a camp in Port-au-Prince holds fresh water. Sanitation and clean water are key to staving off cholera, and public health officials are launching a massive education effort using text messages and radio broadcasts. Christopher Joyce/NPR hide caption

itoggle caption Christopher Joyce/NPR

Two trucks crashed on a road toward Saint-Marc in Haiti. One truck was carrying Coke bottles, the other was full of people. The head-on collision knocked the bed off the back of one truck, killing several and injuring many more. Christopher Joyce/NPR hide caption

itoggle caption Christopher Joyce/NPR

Philomena Josephat and her father Joseph at St. Nicholas Hospital. Joseph, who has recovered from cholera, said: "I've never felt sick like that before, but I lost a child, and since then my health left me. And with this, that's even worse. I felt like I was dying." Carl Thalemaque for NPR hide caption

itoggle caption Carl Thalemaque for NPR

Earlier this month, Mexican soldiers stack bails of marijuana -- 134 tons of it -- to be burned near the city of Tijuana. Many people in the Mexican border town do not believe that legalizing recreational marijuana use in California will change the level of violence driven by Mexico's drug trade. Francisco Vega/Getty Images hide caption

itoggle caption Francisco Vega/Getty Images

A banner in a street in Port-au-Prince urges people to wash with soap. Though the cholera epidemic has stabilized for now, health officials are working to contain and quell the outbreak and warn that the epidemic is not yet over. Nicholas Kamm/AFP/Getty Images hide caption

itoggle caption Nicholas Kamm/AFP/Getty Images

A closeup of Eurytemora, a kind of copepod that serves as a reservoir for the cholera bacterium. Courtesy of Dr. Rita Colwell, University of Maryland hide caption

itoggle caption Courtesy of Dr. Rita Colwell, University of Maryland