Comparison of PCR and Conventional Serological Methods for Detection of Brucella spp. in Ovine and Caprine Blood Serum

Document Type : Original Articles

Authors

1 Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran

2 Department of Pathobiology, Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran

3 Zabol Veterinary Office, Sistan and Baluchestan Provincial Veterinary Service, Iranian Veterinary Organization, Zabol, Iran

4 Stuff in Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran

Abstract

Brucellosis is an anthropozoonotic disease. Infection of livestock with Brucella is endemic in most parts of Iran. Sistan-Baluchestan is bordered on the east by the countries of Afghanistan and Pakistan. The high prevalence of brucellosis in livestock in the eastern neighboring countries results in transmission of the disease to this province. The present research aimed to determine the prevalence of brucellosis in small ruminants in the Sistan region of Iran and to compare serological and molecular tests for the detection of brucellosis. Blood samples were taken from 150 randomly selected sheep and goats, and sera were separated. All sera were analyzed by serological (Wright and 2-ME) and molecular (Polymerase Chain Reaction (PCR)) tests. Serological tests were carried out according to the instructions of the Iranian Veterinary Organization The degree of agreement between serological tests and PCR was determined by kappa value. In this study, 17 cases (11.3%) were identified as positive by the PCR method. Wright and 2-ME tests had the highest agreement with PCR in titers ≥2/80 and ≥2/40, respectively. The results of this study show that the brucellosis in sheep and goats has a greater prevalence in the Sistan region than in most other parts of Iran, and this is important in terms of public health. It is suggested that brucellosis vaccination coverage in livestock be increased in this area and that the people in Sistan region must be notified about methods for preventing brucellosis. Also, further studies to compare conventional serologic tests with the gold standard test are recommended.

Keywords

Main Subjects


Article Title [French]

Comparaison de la RPC et des Méthodes Sérologiques Conventionnelles Pour la Détection de Brucella spp. dans le Sérum Sanguin des Ovins et des Caprins

Abstract [French]

La brucellose est une infection anthropozoonotique. L'infection du bétail par Brucella est endémique dans la plupart des régions d'Iran. Le Sistan-Balûchestân est bordé à l'est par les pays de l'Afghanistan et du Pakistan. La forte prévalence de la brucellose chez le bétail dans les pays voisins de l'est entraîne la transmission de la maladie à cette province. La présente recherche visait à déterminer la prévalence de la brucellose chez les petits ruminants dans la région du Sistan en Iran et à comparer les tests sérologiques et moléculaires pour la détection de la brucellose. Des échantillons de sang ont été prélevés sur 150 moutons et chèvres sélectionnés au hasard, et les sérums ont été séparés. Tous les sérums ont été analysés par des tests sérologiques (Wright et 2-ME) et moléculaires (Réaction de polymérisation en chaîne (RPC)). Les tests sérologiques ont été effectués conformément aux instructions de l'Organisation vétérinaire iranienne. Le degré de concordance entre les tests sérologiques et la RPC a été déterminé par la valeur de kappa. Dans cette étude, 17 cas (11.3%) ont été identifiés comme positifs par la méthode RPC. Les tests Wright et 2-ME présentaient la plus grande concordance avec la RPC pour les titres ≥2/80 et ≥2/40, respectivement. Les résultats de cette étude montrent que la brucellose chez les moutons et les chèvres a une prévalence plus élevée dans la région du Sistan que dans la plupart des autres régions d'Iran, et cela est important en termes de santé publique. Il est suggéré que la couverture vaccinale contre la brucellose chez le bétail soit augmentée dans cette zone et que les habitants de la région du Sistan soient informés des méthodes de prévention de la brucellose. De plus, d'autres études pour comparer les tests sérologiques conventionnels avec le test de référence sont recommandées.

Keywords [French]

  • Brucella
  • RPC
  • tests sérologiques
  • Sistan
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