Levantamento Epidemiológico da Raiva no Estado de Minas Gerais no Período de 2002 a 2006.

Abstract

Rabies is an infectious and contagious disease that affects mammals including humans and is present in all the continents except Oceania It is caused by the genus Lyssavirus and is characterized by acute and fatal encephalitis In Brazil rabies is considered endemic but in herbivorous animals it predominates in the states of Minas Gerais and Goiás respectively and in decreasing order The main transmitters of rabies to humans are dogs followed by bats As regards herbiborous animals the main transmitters are hematophagous bats The purpose of this paper was to evaluate the diagnosis of human and animal rabies in the State of Minas Gerais observing by means of statistical analyses of time series the tendency and seasonability of bovine rabies Eight thousand and nine hundred and seven samples were analyzed by means of DIF (direct immmunofluorescence) of several animal species including humans in the 2002-2006 period The samples composed by fragments of nervous tissue came from animals and humans with nervous symptoms and clinical signs of rabies Among the samples 1.533 (17.21%) were DIF positive The DIF negative samples (7.373, or 82.79%) were submitted to the MI (mouse inoculation) examination and gave rabies-positive results in 71 samples (0.96%) Of all the species submitted to DIF and MI examinations the highest number of positive cases occurred in bovines (1.344 cases) followed by equines (140) bats (71) dogs (30) humans (5) swines (4)goats (3)sheeps (3) cats (2) asinines (1) and buffaloes (1)Bovine rabies was statistically analyzed by means of the sign test (Cox-Stuart) adapted to a regression model to determine tendency and the Fisher test to determine seasonability With regard to tendency in bovines a decreasing number of rabies-positive cases was detected at a proportion of 0.1427 cases a month A cyclical seasonability characterized by the existence of 3 annual cycles (January to April May to August and September to December) was also determined where bovine rabies occurred mainly in February (first cycle) July (second cycle) and October (third cycle) with a similar characteristic of each cycle in all the years of the study Bovine rabies was diagnosed in all the 10 macro-regions of Minas Gerais but it was predominant in the South the Center and in the Minas Gerais Triangle (Triângulo Mineiro) The regions with the least number of focuses was the North the Northwest and the Jequitinhonha/Mucuri Valley For controlling bats Desmodus rotundus 5.294 shelters were registered where 39.137 bats of such a species were captured and treated with a bat killing paste Rabies is a disease that needs for its control continuous activities of epidemiological vigilance sanitary education animal immunization and populational control of its transmitters