Microbiota associated with tramp ants in a Brazilian University Hospital.

Our aim was to study the fauna of ants in the Hospital Universitário of the Universidade Federal do Triângulo Mineiro, municipality of Uberaba, Minas Gerais State, Brazil, as well as to identify the microorganisms the ants carry and their patterns of resistance to antibiotics. Sterile tubes (traps) containing honey were used to attract the ants. Traps were exposed for 3h, and those which attracted ants were considered the test group, while the ones that did not attract the insects constituted the control group. Only the ant species Tapinoma melanocephalum (Fabricius) was sampled. Sixty microorganisms were isolated from the sampled ants, including seven Gram-positive bacilli, 14 Gram-negative bacilli, 22 Gram-positive cocci and 17 filamentous fungi. Pseudomonas, Staphylococcus and Group D Streptococcus were the microorganisms with the highest resistance to the tested antibiotics. The ants should be considered an important vector of infections as they carry several pathogenic microorganisms, spreading them on the surface of sterile materials, equipment and uncontaminated food. It is impossible to define the exact role of ants in nosocomial infections at this moment; however, this issue must be better studied and special attention must be given by the commissions of Nosocomial Infection Control.

Microbiota associated with tramp ants in a Brazilian University Hospital / Microbiota associada às formigas urbanas em um Hospital Universitário Brasileiro

Our aim was to study the fauna of ants in the Hospital Universitário of the Universidade Federal do Triângulo Mineiro, municipality of Uberaba, Minas Gerais State, Brazil, as well as to identify the microorganisms the ants carry and their patterns of resistance to antibiotics. Sterile tubes (traps) containing honey were used to attract the ants. Traps were exposed for 3h, and those which attracted ants were considered the test group, while the ones that did not attract the insects constituted the control group. Only the ant species Tapinoma melanocephalum (Fabricius) was sampled. Sixty microorganisms were isolated from the sampled ants, including seven Gram-positive bacilli, 14 Gram-negative bacilli, 22 Gram-positive cocci and 17 filamentous fungi. Pseudomonas, Staphylococcus and Group D Streptococcus were the microorganisms with the highest resistance to the tested antibiotics. The ants should be considered an important vector of infections as they carry several pathogenic microorganisms, spreading them on the surface of sterile materials, equipments and uncontaminated food. It is impossible to define the exact role of ants in nosocomial infections at this moment; however, this issue must be better studied and special attention must be given by the commissions of Nosocomial Infection Control.

O objetivo deste estudo foi conhecer a fauna de formigas existente no Hospital Universitário da Universidade Federal do Triângulo Mineiro, Uberaba, MG, bem como as espécies de microrganismos transportadas por elas, além de identificar o padrão de resistência destes microrganismos a antimicrobianos. Para atrair as formigas, utilizaram-se tubos estéreis contendo mel. Após período de exposição de 3h, os mesmos foram tampados. Os tubos que atraíram formigas foram considerados o grupo teste e os que não atraíram o controle. Apenas Tapinoma melanocephalum (Fabricius) foi amostrada. O isolamento de microrganismos dos exemplares de T. melanocephalum apontou 60 espécies, entre as quais sete eram bacilos Gram positivo, 14 bacilos Gram negativo, 22 cocos Gram positivo e 17 fungos filamentosos. Pseudomonas, Staphylococcus e Streptococcus do grupo D foram os microrganismos que apresentaram maior resistência aos antibióticos. As formigas devem ser consideradas um importante vetor de infecções, pois são carreadoras de microrganismos, levando-os na superfície de seu corpo para materiais estéreis, equipamentos e alimentos não-contaminados. Não é possível definir o papel exato das formigas em infecções nosocomiais. No entanto, este deve ser melhor avaliado e atenção especial deve ser dada pelas comissões de Controle de Infecções Hospitalares.