Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.

Salmonella Typhimurium, a zoonotic pathogen, is regarded as a major health and economic concern worldwide. Recently, monophasic variants of this serovar have been significantly associated with human gastroenteritis outbreaks globally, making its accurate identification essential for epidemiological...

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Main Authors: Reza Farahani Khaltabadi, Nader Shahrokhi, Mina Ebrahimi-Rad, Parastoo Ehsani
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2019-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0213726
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author Reza Farahani Khaltabadi
Nader Shahrokhi
Mina Ebrahimi-Rad
Parastoo Ehsani
author_facet Reza Farahani Khaltabadi
Nader Shahrokhi
Mina Ebrahimi-Rad
Parastoo Ehsani
author_sort Reza Farahani Khaltabadi
collection DOAJ
description Salmonella Typhimurium, a zoonotic pathogen, is regarded as a major health and economic concern worldwide. Recently, monophasic variants of this serovar have been significantly associated with human gastroenteritis outbreaks globally, making its accurate identification essential for epidemiological and control purposes. We have identified and analyzed 150 S. Typhimurium from 884 Salmonella genus isolated from humans, domestic animals, poultry, food items and abattoirs origins. The Salmonella isolates were obtained from Iranian National Veterinary Reference Laboratories of 9 provinces during 2007-2016, and from five hospitals in Tehran in 2015. The isolates were evaluated biochemically, serologically, and by PCR amplification of invA, mdh, STM4492, fliC, fljA, fljB, hin genes, IS200 and DT104. invA and mdh genes were used to confirm the S. Typhimurium serotype, fliC and fljB genes for determination of monophasic variants and amplification of IS200 to discriminate the monophasic variants from the closely related serotypes. We identified 78.6% (118/150) as classical S. Typhimurium (fliC, fljB and IS200 positive), 12.6% (19/150) were IS200 negative from all isolates. DT104 is another marker for S.Typhimurium serovar typing. Contrary to EFSA guidelines 20.6% (19/29) of human isolates that lacked IS200 insertion sequence, were confirmed as S.Typhimurium. Compared to the North American/European isolates the low prevalence of fljB negative 6% (9/150) and the high abundance of fliC negative 23.3% (35/150) isolates also were indicative of a different regional atypical population. Studies have shown that the prevalence of monophasic (fljB-) S. Typhimurium worldwide is promoted by the Swine industry. Thus, one reason for this high number of different atypical strains could be inhibition of swine breeding system (house hold and industry) in Iran. These results demonstrate a need for a modified identifying protocol to overcome the regional differences.
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spelling doaj.art-bba4188b4b2f469d8f5209f5811c6fe42022-12-21T19:50:36ZengPublic Library of Science (PLoS)PLoS ONE1932-62032019-01-01143e021372610.1371/journal.pone.0213726Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.Reza Farahani KhaltabadiNader ShahrokhiMina Ebrahimi-RadParastoo EhsaniSalmonella Typhimurium, a zoonotic pathogen, is regarded as a major health and economic concern worldwide. Recently, monophasic variants of this serovar have been significantly associated with human gastroenteritis outbreaks globally, making its accurate identification essential for epidemiological and control purposes. We have identified and analyzed 150 S. Typhimurium from 884 Salmonella genus isolated from humans, domestic animals, poultry, food items and abattoirs origins. The Salmonella isolates were obtained from Iranian National Veterinary Reference Laboratories of 9 provinces during 2007-2016, and from five hospitals in Tehran in 2015. The isolates were evaluated biochemically, serologically, and by PCR amplification of invA, mdh, STM4492, fliC, fljA, fljB, hin genes, IS200 and DT104. invA and mdh genes were used to confirm the S. Typhimurium serotype, fliC and fljB genes for determination of monophasic variants and amplification of IS200 to discriminate the monophasic variants from the closely related serotypes. We identified 78.6% (118/150) as classical S. Typhimurium (fliC, fljB and IS200 positive), 12.6% (19/150) were IS200 negative from all isolates. DT104 is another marker for S.Typhimurium serovar typing. Contrary to EFSA guidelines 20.6% (19/29) of human isolates that lacked IS200 insertion sequence, were confirmed as S.Typhimurium. Compared to the North American/European isolates the low prevalence of fljB negative 6% (9/150) and the high abundance of fliC negative 23.3% (35/150) isolates also were indicative of a different regional atypical population. Studies have shown that the prevalence of monophasic (fljB-) S. Typhimurium worldwide is promoted by the Swine industry. Thus, one reason for this high number of different atypical strains could be inhibition of swine breeding system (house hold and industry) in Iran. These results demonstrate a need for a modified identifying protocol to overcome the regional differences.https://doi.org/10.1371/journal.pone.0213726
spellingShingle Reza Farahani Khaltabadi
Nader Shahrokhi
Mina Ebrahimi-Rad
Parastoo Ehsani
Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
PLoS ONE
title Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
title_full Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
title_fullStr Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
title_full_unstemmed Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
title_short Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection.
title_sort salmonella typhimurium in iran contribution of molecular and is200 pcr methods in variants detection
url https://doi.org/10.1371/journal.pone.0213726
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