Biochemical and molecular identification of Gram-positive isolates with β-hemolysis activity isolated from the nasal swab of pigs during the human meningitis outbreak in Badung Regency, Bali-Indonesia

Vet World Vol.15 January-2022 Article-18

Research Article

Veterinary World, 15(1): 140-146

https://doi.org/10.14202/vetworld.2022.140-146

K. J. Putra Pinatih¹, I. W. Suardana², I. D. M. Sukrama¹, I. B. N. Swacita², and R. K. Putri³

1. Department of Clinical Microbiology, Faculty of Medicine, Udayana University, Jl. PB. Sudirman Denpasar-Bali, 80234, Indonesia.
2. Department of Preventive Veterinary Medicine, Laboratory of Veterinary Public Health, Faculty of Veterinary Medicine, Udayana University, Jl. PB. Sudirman Denpasar-Bali, 80234, Indonesia.
3. Department of Veterinary Medicine, Faculty of Veterinary Medicine, Udayana University, Jl. PB. Sudirman Denpasar-Bali, 80234, Indonesia.

Background and Aim: The nasal cavity of a pig serves as an entry point and a habitat for the colonization of commensal microbes and pathogenic bacteria. Based on biochemical and serological tests, Streptococcus β-hemolytic Group C was identified as the Gram-positive bacteria, which resulted in the 1994 outbreak and death of thousands of pigs in Bali. Furthermore, this agent is zoonotic and frequently results in the development of meningitis lesions in the infected pig. Recently, a meningitis outbreak in humans was also reported after the consumption of pig-derived foods at Sibang Kaja, Badung-Bali. This study aimed to identify and characterize Gram-positive β-hemolytic organisms collected from nasal swab of pigs from the outbreak area, as well as to compare API Kit and 16S rRNA gene analysis methods.

Materials and Methods: This study commenced with the cultivation of two isolates, Punggul Swab Nasal (PSN) 2 and PSN 19, which were characterized by β-hemolysis activity. These samples were then conventionally and molecularly identified using Kit API 20 Strep and 16S ribosomal RNA (rRNA) gene primers, respectively.

Results: Using the Kit API 20 Strep, both isolates were identified as Enterococcus faecium, which was previously classified as Group D Streptococci. Based on the 16S rRNA gene sequencing, PSN 2 and PSN 19 were molecularly confirmed to have 99 and 98.1% similarities with E. faecium (NR042054), respectively. Furthermore, both isolates share the same clade in the phylogenetic tree analysis.

Conclusion: Using Kit API 20 Strep and 16S rRNA gene analysis, the PSN 2 and PSN 9 Gram-positive isolates with β-hemolysis activity from pig nasal swabs were identified as E. faecium. Keywords: 16S ribosomal RNA gene, Gram-positive bacteria, Kit API 20 Strep, nasal of pig, phylogenetic tree.

Keywords: 16S ribosomal RNA gene, Gram-positive bacteria, Kit API 20 Strep, nasal of pig, phylogenetic tree.

How to cite this article: Pinatih KJP, Suardana IW, Sukrama IDM, Swacita IBN, Putri RK (2022) Biochemical and molecular identification of Gram-positive isolates with β-hemolysis activity isolated from the nasal swab of pigs during the human meningitis outbreak in Badung Regency, Bali-Indonesia, Veterinary World, 15(1): 140-146.

Received: 11-08-2021 Accepted: 20-12-2021 Published online: 25-01-2022

Corresponding author: E-mail: wayan_suardana@unud.ac.id

DOI: 10.14202/vetworld.2022.140-146

Copyright: Pinatih KJP, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.