The researchers investigated the rapid emergence of fluoroquinolone resistance in Salmonella enterica serotype choleraesuis in Taiwan.
The findings of the study were reported in the latest issue of the New England Journal of Medicine.
Pigs were evaluated as a potential source of the resistant Salmonella.
A total of 501 clinical isolates of S. enterica serotype choleraesuis were recovered in the authors' hospital from 1987 through 2000.
The proportion of total Salmonella isolates made up by S. enterica serotype choleraesuis decreased from an average of 8% before 1995 to 3% in 1996 through 1998.
The researchers found that, during 1999 and 2000, this proportion increased significantly, to an average of 5%.
|60% of isolates resistant to ciprofloxacin in 2001.
| New England Journal of Medicine |
Ciprofloxacin resistance in S. enterica serotype choleraesuis has been observed since 2000. In the third quarter of 2001, 60% of isolates were found to be resistant to ciprofloxacin.
Molecular typing indicated that the primary source of S. enterica serotype choleraesuis isolates was herds of swine.
All the resistant isolates from humans and swine had mutations that led to the substitution of phenylalanine for serine at position 83 and asparagine for aspartic acid at position 87 in the gene for DNA gyrase A.
Dr Cheng-Hsun Chiu, of the Chang Gung Children's Hospital, Taoyuan, Taiwan, said on behalf of the group, "This investigation in Taiwan indicates that fluoroquinolone-resistant S. enterica serotype choleraesuis can spread from swine to humans."
"The use of fluoroquinolones in food animals should be prohibited," it was concluded.