A case control study of Salmonella SPP. infection in stray dogs in Tehran shelters and the correlation between paraclinical tests results and clinical findings

Document Type: Original Articles


1 Department of internal medicine, Faculty of Specialized Veterinary Science, Islamic Azad University, Science and Research Branch, Tehran, Iran

2 Department of Microbiology, Faculty of Specialized Veterinary Science, Islamic Azad University, Saveh, Iran


Salmonellosis as a zoonotic disease in dogs is not fully understood, and various reports have pointed to the transmission of antibiotic-resistant salmonella from dogs to humans. The current study aimed to evaluate the serologic and bacteriologic prevalence of Salmonella spp. in stray dogs placed in animal shelters around Tehran, compare the results to those of asymptomatic dogs, and determine the serotype of isolated species, as well as their antibiotic susceptibility pattern. A total of 100 fecal swab and blood samples were obtained from symptomatic and apparently healthy dogs (clinically) placed in four animal shelters around Tehran, Iran. Fecal and blood culture, as well as dog food culture, tube agglutination test, serotyping, and antibiotic susceptibility testing were performed on the samples. Fever, lethargy, diarrhea, and abdominal pain were observed in all the dogs in the case group, and bloody diarrhea was the least commonly detected symptom in clinical examination. A number of 11 and 4 collected fecal swabs from the case and control groups were positive for Salmonella spp., respectively. The polymerase chain reaction (PCR) also confirmed the laboratory tests results. Blood culture on the selective medium was negative for all the cases. Moreover, 60% and 100% of dogs in the case and control groups showed inflammatory markers in their blood test. The tube agglutination test was positive for 12% of the samples from the case group, while it was positive only for 5% of cases in the control group. The highest and lowest antibiotic resistance was observed against gentamicin and ciprofloxacin from the case group, respectively. Salmonella spp. infection in stray dogs placed in animal shelters is a great public health concern. In this regard, it is recommended that these animals be regularly monitored since they serve as Salmonella carriers.


Article Title [French]

La Salmonellose chez les Chiens Errants dans les Refuges de Téhéran et la Corrélation entre les Résultats des Tests Paracliniques et les Résultats Cliniques: Une Étude Cas-Témoins

Abstract [French]

La salmonellose en tant que maladie zoonotique chez le chien n'est pas entièrement comprise. Divers rapports ont montré la transmission de salmonelles résistantes aux antibiotiques du chien à l'homme. Cette étude visait à évaluer la prévalence sérologique et bactériologique des espèces de salmonelle chez les chiens errants dans les refuges pour animaux de la banlieue de Téhéran, en Iran. Les résultats obtenus ont été comparés à ceux des chiens asymptomatiques afin de déterminer le sérotype des espèces isolées, ainsi que leur profil de sensibilité aux antibiotiques. Au total, 100 écouvillons fécaux et échantillons sanguins ont été prélevés sur des chiens symptomatiques et apparemment sains (cliniquement) placés dans quatre refuges pour animaux autour de Téhéran. Les échantillons ont été étudiés en termes de culture fécale et sanguine, de culture d'aliments pour chiens, de test d'agglutination en tube, de sérotypage et de test de sensibilité aux antibiotiques. Selon nos résultats, des symptômes diverses incluant fièvre, léthargie, diarrhée et douleurs abdominales ont été observés chez tous les chiens du groupe infecté symptomatique, tandis que la diarrhée sanglante était le symptôme le moins fréquemment détecté à l'examen clinique. Au total, 11 et 4 prélèvements fécaux étaient respectivement positifs pour la salmonelle dans les groupes symptomatiques et contrôle. La réaction en chaîne de la polymérase a également confirmé ces résultats. L'hémoculture sur milieu sélectif était négative pour tous les cas. De plus, les résultats des tests sanguins ont montré la présence de marqueurs inflammatoires dans respectivement 60% et 100% des chiens des groupes symptomatiques et témoins. Le test d'agglutination en tube était positif pour 12% des chiens symptomatiques; alors qu’il était positif pour 5% des cas dans le groupe témoin. La résistance aux antibiotiques la plus élevée et la plus faible a été respectivement observée contre la gentamicine et la ciprofloxacine chez les ciens infectés. La salmonellose est une grande préoccupation de santé publique chez les chiens errants placés dans des refuges pour animaux. Il est recommandé de surveiller régulièrement ces animaux car ils sont considérés comme porteurs potentiels de la salmonelle.

Keywords [French]

  • Salmonella spp
  • Chiens errants
  • Refuges
  • Maladies zoonotiques
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