Open AccessAssociation between the use of colistin for short-term treatment of Gram-negative bacterial infections and the emergence of colistin-resistant Enterobacteriaceae in swine from selected swine farms in Thailand
Author(s) -
Pariwat Poolperm,
Teerawit Tangkoskul,
Chakkrapong Seenama,
Naruemon Maknakhon,
Visanu Thamlikitkul
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0238939
Subject(s) - colistin , enterobacteriaceae , microbiology and biotechnology , biology , feces , medicine , antibiotics , escherichia coli , biochemistry , gene
Long-term use of colistin for preventing Gram-negative bacterial infections in food animals was prohibited in Thailand in 2017, but it is permitted for short-term treatment. This study aimed to investigate association between the use of colistin for short-term treatment of infection and the emergence of colistin-resistant Enterobacteriaceae in swine. The current study was conducted at 2 selected swine farms in Thailand. Neither farm has used colistin to prevent infection for longer than 1 year. Rectal swabs were collected from the same 66 pigs at birth, and on days 7, 14, 21, 28, and 60. Colistin was used to treat sick pigs for up to 3 days. Additional rectal swabs were collected during colistin treatment. Rectal swabs were analyzed for colistin-resistant Enterobacteriaceae and the mcr-1 gene. Results revealed that colistin-resistant Enterobacteriaceae were absent at birth. Some pigs at both farms had diarrhea and received colistin treatment during days 2–27. Colistin-resistant Enterobacteriaceae were detected in 13.3–50.0% of sick and healthy pigs. No sick pigs were observed during days 28–60, and colistin was not used during that period. Colistin-resistant Enterobacteriaceae were detected in 2.8–10.0% of healthy pigs on day 28, and in 0–3.4% of healthy pigs on day 60. The mcr-1 gene was detected in 57.6% of colistin-resistant Enterobacteriaceae isolates. Short-term treatment with colistin was found to be associated with the emergence of colistin-resistant Enterobacteriaceae in swine. Colistin-resistant Enterobacteriaceae rapidly emerged after colistin use, and rapidly decreased or disappeared after its discontinuation.