ABSTRACT
Brucellosis is a common zoonotic disease caused by Brucella and is an epidemic worldwide. Currently, the most effective way to prevent and control the disease in animals is to use live, attenuated vaccines A19 strain. In China, the live attenuated Brucella abortus vaccine is widely used in animal immunization. To detect and confirm which vaccine strain caused the infection, we developed a new method to distinguish A19 strain from non-A19 strains. By comparing the genomic sequences of A19 and wild strain 2,308, we identified signature sequences that are unique to A19. A PCR assay for specific A19 identification was developed based on the genetic marker ABC transporter permease gene. Samples from the outbreak patients were then analysed using the universal quantitative PCR and A19-specific PCR assay, and the A19 strain was successfully identified in them, providing pathogenic evidence of the vaccine-derived infection outbreak. This combined A19-specific differential diagnosis method can provide a means to distinguish between animal vaccine immunization, natural infection and human infection by the vaccine strain. This strategy also has applications in diagnosis, epidemiology and surveillance of A19-related immunizations or infections.
Subject(s)
Brucella Vaccine , Brucella abortus/classification , Brucella abortus/genetics , Brucellosis/diagnosis , Brucellosis/microbiology , Real-Time Polymerase Chain Reaction , Animals , Brucella Vaccine/immunology , Brucella abortus/immunology , Brucellosis/epidemiology , Brucellosis/veterinary , China , Disease Outbreaks , Genome, Bacterial , Humans , Occupational Diseases/diagnosis , Occupational Diseases/microbiology , Sensitivity and Specificity , Vaccination/veterinary , Vaccines, AttenuatedABSTRACT
Objective To investigate the relationship between brucellosis arthritis of the hip and femoral head necrosis.Methods In August 2007 to August 2013,16 diagnosed and hospitalized patients with brucellosis complicated with femoral head necrosis in Heilongjiang Land Reclamation Bureau General Hospital were chosen as the objects of observation,and the patients' hospitalization information was analyzed retrospectively.Patients' medical records were investigated and analyzed.Observations included general condition of the patient,clinical symptoms and signs,imaging,pathology,treatment and curative effect.Results All the 16 patients had definite clinical manifestations of hip arthritis and femoral head necrosis including hip pain,limited mobility,positive 4 test,limp or bedridden,and sick limb muscle atrophy.Imaging examination:X-ray computer tomography (CT) showed cystic change and deformation collapse of femoral head.Magnetic resonance imaging(MRI) showed low signal on weighted T1 images,high signal on weighted T2 and soft tissue granulation hyperplasia could be seen in the hip joint.Pathological examination:most femoral bone tissue necrosis,dissolved,bone cells disappeared,a few bone cells present,and some fibrous tissue hyperplasia.Patients were treated with antibiotics according to the treatment principles of brucellosis,and the effect was obvious.Conclusions There is a causal relationship between brucellosis arthritis of the hip and femoral head necrosis.Therefore,positive and effective treatment of brucellosis arthritis of the hip in the early stages is crucial to prevent the occurrence of femoral head necrosis.
