Rodríguez discovered she was a carrier of Chagas while pregnant, but her daughter tested negative. Elvira Hernández learned of Chagas when her son tested positive, saying, “I was scared when I read about it being a silent killer. ”Chagas, spread by kissing bugs, infects 8 million in Latin America, causing 12,000 deaths annually. In the U.S., 300,000 are infected, but it’s less common.