Dengue epidemic in Belém, Pará, Brazil, 1996-97.

We describe clinical and epidemiologic findings during the first epidemic of dengue fever in Belem Para State Brazil in 1996-97. Of 40237 serum samples 17440 (43%) were positive for dengue by virus isolation or serologic testing. No hemorrhagic cases or deaths were reported. Dengue fever (DF) and dengue hemorrhagic fever (DHF) are caused by infection with one of the four serotypes of dengue virus (DEN-1 DEN-2 DEN-3 and DEN-4) transmitted by Aedes aegypti mosquitoes. In Brazil DF epidemics reported in the 1980s and 1990s involved more than a million cases. However only 671 DHF cases were diagnosed with 26 deaths. (excerpt)