P3-80 Arcobacter: Comparison of Isolation Methods, Diversity and Potential Pathogenic Factors in Commercially Retailed Chicken Breast Meat from Costa Rica

Wednesday, August 6, 2014
Exhibit Hall D (Indiana Convention Center)
Maria Laura Arias, Universidad de Costa Rica, San Jose, Costa Rica
Karolina Fallas, Universidad de Costa Rica, San José, Costa Rica
Heriberto Fernandez, Universidad Austral de Chile, Valdivia, Chile
Carlos Rodríguez, Universidad de Costa Rica, San José, Costa Rica
Introduction: Arcobacter species have been recognized as potential food and waterborne pathogens. The lack of standardized isolation methods as well as the relatively scarce knowledge about their prevalence and distribution as emerging pathogens are due to the limitations in their detection and identification.

Purpose: This study aimed to determine the presence and the identification of Arcobacter in chicken breast samples commercially retailed in San José, Costa Rica, as well as to describe the adherence and invasive potential of the strains to human cells (HEp-2). 

Methods: Fifty chicken breast samples were collected from retail markets in the metropolitan area of the country. Six different isolation methodologies were applied for the isolation of Arcobacter. Isolation strategies consisted of combinations of enrichments in de Boer or Houf selective broths and subsequent isolation in blood agar (directly or with a previous passive membrane filtration step) or Arcobacter selective agar. Suspicious colonies were identified with a genus-specific PCR, whereas species-level identification was achieved with a multiplex-PCR. 

Results: The overall isolation frequency of Arcobacter was 56%. From the isolation strategies, the combination of enrichment in Houf selective broth followed by filtration on blood agar showed the best performance, with a sensitivity of 89% and a specificity of 84%. A total of 46 isolates were confirmed as Arcobacter with the genus-specific PCR, from which 27 (59%) corresponded to A. butzleri, 9 (19%) to A. cryaerophilus and 10 (22%) were not identified, with this multiplex PCR. Regarding the potential pathogenicity, 75% of the isolates presented adherence to HEp-2 cells, while only 22% were invasive to that cell line. All the invasive strains were A. butzleri or non-identified strains.

Significance: The results evidence the presence of potentially pathogen Arcobacter in poultry and highlight the recognition it should receive from public health authorities.