SEROLOGICAL SURVEY OF Ehrlichia SPECIES IN DOGS, HORSES AND HUMANS: ZOONOTIC SCENERY IN A RURAL SETTLEMENT FROM SOUTHERN BRAZIL

SUMMARY The aims of this study were to determine the seroprevalence of Ehrlichia spp. and risk factors for exposure in a restricted population of dogs, horses, and humans highly exposed to tick bites in a Brazilian rural settlement using a commercial ELISA rapid test and two indirect immunofluorescent assays (IFA) with E. canis and E. chaffeensis crude antigens. Serum samples from 132 dogs, 16 horses and 100 humans were used. Fifty-six out of 132 (42.4%) dogs were seropositive for E. canis. Dogs > one year were more likely to be seropositive for E. canis than dogs ≤ one year (p = 0.0051). Ten/16 (62.5%) and 8/16 (50%) horses were seropositive by the commercial ELISA and IFA, respectively. Five out of 100 (5%) humans were seropositive for E. canis and E. chaffeensis. Rhipicephalus sanguineus (n = 291, 97.98%) on dogs and Amblyomma cajennense (n = 25, 96.15%) on horses were the most common ticks found. In conclusion, anti-Ehrlichia spp. antibodies were found in horses; however, the lack of a molecular characterization precludes any conclusion regarding the agent involved. Additionally, the higher seroprevalence of E. canis in dogs and the evidence of anti-Ehrlichia spp. antibodies in humans suggest that human cases of ehrlichiosis in Brazil might be caused by E. canis, or other closely related species

Formas graves de leptospirose: aspectos clínicos, demográficos e ambientais Severe forms of leptospirosis: clinical, demographic and environmental aspects

São descritas as características de 1.016 pacientes internados com leptospirose no Hospital Couto Maia, Salvador, BA, entre 1993 e 1997. Aumento na precipitação pluviométrica mostrou relação com aumento do número de internamentos no mês subsequente. Sexo masculino correspondeu a 81,1% (824/1.016); a média da idade foi 35,7±15,4 anos. Quase 94% (778/829) dos 829 com informação sobre raça eram negros ou mulatos. Para idade igual ou superior a 18 anos, quase 93% não cursaram o segundo grau. A média do período de incubação foi estimado em 6,3±3,9 dias. A duração dos sintomas foi em média 6,1±2,4 dias. Episódios hemorrágicos corresponderam a 14,3% (145/1.016). A letalidade entre 1.009 pacientes não transferidos foi de 14,2% (143/1.009). Insuficiência renal foi a causa atribuída de morte em 76,2% (109/143). Os dados indicam que leptospirose é estreitamente relacionada com baixos níveis socioeconômicos e que aumento da precipitação pluviométrica precede surtos epidêmicos.<br>Characteristics of 1,016 patients hospitalized with leptospirosis in the Hospital Couto Maia, Salvador, BA, Brazil, between 1993 and 1997 are described. Higher pluviometric precipitation was related to an increase in the number of hospitalizations during the following month. Males corresponded to 81.1% (824/1,016) of these; mean age was 35.7±15.4 years. Almost 94% (778/829) of the 829 patients with information about race were black or mulatto (mixed race). For ages 18 years or above, almost 93% had not completed high school level. The mean incubation period was estimated as 6.3±3.9 days. Average duration of symptoms was 6.1±2.4 days. Hemorrhagic events corresponded to 14.3% (145/1,016). The case-fatality rate among 1,009 patients that were not transferred was 14.2% (143/1,009). Renal failure was the attributable cause of death in 76.2% (109/143). The data indicate that leptospirosis is closely related to lower socioeconomic levels, and that higher pluviometric precipitation antecedes the outbreaks