Journal of Bacteriology & Parasitology

Investigation and molecular typing of Brucella isolated from dairy cattle herd immunized with Brucella abortus RB51 vaccine in Egypt

3^rd International Congress on Bacteriology and Infectious Diseases

August 04-06, 2015 Valencia, Spain

Gamal Wareth1,2,3, Falk Melzer1, Uwe Roesler2, Lisa D Sprague1 and Heinrich Neubauer1

Scientific Tracks Abstracts: J Bacteriol Parasitol

Abstract:

Brucellosis is still a common in capacitating zoonoses that affecting wide range of domesticated and wild animals as well
as humans. Brucella was firstly described by Sir David Bruce in 1887 in human. Fifty two years later (1939), the disease
was reported in Egypt for the first time in a scientific report, however the doubt still exist if, whether the disease is endemic
in Egypt since thousands of years. Since then the disease remained endemic nationwide and affecting all livestock animals. In
Egypt, brucellosis control programs for bovines are based on a test and slaughter policy as well as vaccination. Recently, Mass
vaccination with attenuated B. abortus RB51 has been approved nationwide; however some may lead to abortion in pregnant
females. The present study was carried out in supposed Brucella-free dairy cow farm in Egypt to investigate a numerous
occurrence of abortions occurred after immunization with B. abortus strain RB51. Among pregnant vaccinated cows, 10%
aborted three months post vaccinations. All aborted cows show positive reaction with Rose Bengal Test (RBT) and Complement
Fixation Test (CFT). B. abortus biovar one was isolated from four aborted fetuses. Conventional biochemical analysis revealed
two B. abortus smooth type and two rough types. The use of the Bruce ladder PCR provided clear differentiation to the field
strain and excludes the RB51 vaccine strain. Genotyping analysis of isolates by Multiple Loci VNTR Analysis (MLVA-16)
cleared that there are two different isolates in the herd with low genetic diversity. Isolated B. abortus are located in a different
cluster from the RB51 vaccinal strains which used in immunization of the herd. In Conclusion: B. abortus bv1 is the source
of outbreak but not the vaccine. RB51 vaccine would only reduce the number of abortions caused by field strains but offer
no protection from infection. The most likely source of infection appears to be the uncontrolled introduction of the agent
via vectors or latent carrier. Eradication of brucellosis is a multidirectional process required combination between ordinary
control program and high biosecurity level in the farms.

Biography :

Gamal Wareth has obtained his Bachelor degree (BVSc) from faculty of Veterinary Medicine, Assuit University, Egypt in 2002. He completed his Master degree in
Veterinary Pathology in 2009 at Benha University, Egypt. Then he enrolled for DVM in Free University of Berlin in collaboration with Friedrich-Loeffler-Institut (FLI),
Germany. He is currently works in NRL of brucellosis at Friedrich-Loeffler-Institut, Institute of Bacterial Infections and Zoonoses in Jena, Germany. The main areas
of his interest are development of diagnostic products; proteomics, epidemiology, molecular epidemiology and microbiology of pathogen level 3 agents (Brucella
spp., Francisella tularensis, Burkholderia mallei/pseudomallei, Bacillus anthracis, Yersinia pestis).