Zoonotic bacteria isolated from wild Passeriformes recovered from animal trafficking in the State of Ceará/Brazil

ABSTRACT The order Passeriformes is one of the most pressured by anthropic actions, especially those related to animal trafficking. Due to poor sanitary and hygienic conditions, the infection of the specimens is favored by virulent and zoonotic pathogens such as strains of Escherichia coli and Salmonella spp., whose isolation in cloacal swabs as well as the analysis of the virulence genes of E. coli strains were the objectives of the study. For this, 120 native wild Passeriformes, received by CETAS/CE were individually evaluated. The isolated strains were submitted to diffusion disc test to determine sensitivity to antimicrobials. In a later stage, PCR was performed for the detection of eight virulence genes from the main E. coli diarrhoeagenic pathogens. Regarding the results, no strain of Salmonella spp. was isolated; however, the occurrence of E. coli was 40.8%. High resistance was observed, mainly to the antimicrobials Tetracycline, Ampicillin and Sulfazotrim, with multi-resistance in 42.8% of the strains. By molecular analysis, four of the nine genes were diagnosed, identifying typical EPEC, atypical EPEC, ETEC, EHEC and EAEC. The results point to the importance of Passeriformes as possible disseminators of zoonoses.

摘要
雀形目（Passeriformes）是受人类活动胁迫最为严重的类群之一，尤以与野生动物非法贸易相关的影响为甚。由于转运及收容过程中卫生条件欠佳，受试标本易被高致病性人畜共患病原体（zoonotic pathogens）感染，如大肠杆菌（Escherichia coli）菌株与沙门氏菌属（Salmonella spp.）。本研究的核心目标为：通过泄殖腔拭子（cloacal swabs）分离上述菌株，并分析大肠杆菌菌株的毒力基因。

本研究共纳入120株由CETAS/CE接收的本土野生雀形目标本，开展单独评估。对分离获得的菌株采用纸片扩散法药敏试验（diffusion disc test），以测定其对抗菌药物的敏感性。后续通过聚合酶链式反应（PCR），检测8种主要致泻性大肠杆菌的毒力基因。

结果显示：未分离得到沙门氏菌属（Salmonella spp.）菌株；大肠杆菌的检出率为40.8%。受试菌株呈现出较高的耐药性，尤其对四环素、氨苄西林与复方新诺明（Sulfazotrim）耐药性显著，其中42.8%的菌株表现为多重耐药（multi-resistance）。分子生物学分析共检出9种目标毒力基因中的4种，成功鉴定出典型肠致病性大肠杆菌（EPEC）、非典型肠致病性大肠杆菌（atypical EPEC）、肠产毒性大肠杆菌（ETEC）、肠出血性大肠杆菌（EHEC）与肠聚集性大肠杆菌（EAEC）。

本研究结果表明，雀形目可作为人畜共患病的潜在传播媒介，其公共卫生防控价值不容忽视。