LA PAZ, Bolivia (CNN)  -- Bolivian officials have declared a health emergency after three deaths attributed to dengue hemorrhagic fever, the often-lethal form of a mosquito-borne disease that more than 1,000 Bolivians are thought to have contracted since November. Brazilian soldiers pour insecticide to fight dengue fever in 2008. Bolivia also is battling the mosquito-borne disease. At least 12 unconfirmed instances of dengue hemorrhagic fever have been reported in the first 17 days of 2009, the official ABI news agency said. About 250 cases of dengue fever, the milder, nonlethal form of the disease, have been confirmed in the past two weeks, said Health Minister Ramiro Tapia in the Los Tiempos de Cochabamba newspaper.
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At least 12 unconfirmed instances of dengue hemorrhagic fever reported in Bolivia
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Bolivia fights disease with 20,000-plus in military, 2.5 tons of insecticide
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Cases of dengue fever usually spike in Bolivia's hot and rainy season
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At least 55,000 contracted disease last year in Brazil
Last year, 55,000 people in southeastern @placeholder contracted the disease.