ABSTRACT
Objective To develop a rapid test for the detection of F1 antigen of Yersinia Pestis based on gold-immunochromatography.Methods F1 antibodies were coupled with colloidal gold to prepare collidal gold reagent,which was used to detect F1 antibodies based on double antigen sandwich.The collidal gold reagent was estimated for its sensitivity specificity and stablity in labs and 1798 samples were detected in 17 surveillance spots.Results The reagent was sensitive to 0.0010 g/L F1 antigens.The reagens kept stable when it had been placed at 4℃ or room-temperature for 12 months and did not react to Yersinia pseudotuberculosis and Yersinia enterolitica.In 17 surveillance labs the reagent was used to test 1798 viscera samples from animal.resulting an accordance rate of 97.11%(1746/1798)to bacterial culture and 96.83%(1741/1798)accordance to reverse indirect hemagglutination assay(RIHA),showing a higher detection rate[9.23%(166/1798)]compared with RIHA[6.79%(122/1798)]and bacterial culture[6.28%(113/1798)].Conclusions The collidal gold reagent,sensitive and specific in diagnosing Yersinia pestis infection of both human and animals,is a rapid method in surveillance spot.
ABSTRACT
<p><b>OBJECTIVE</b>To apply and evaluate new methods regarding specific gene and antigen detection in plague surveillance program.</p><p><b>METHODS</b>1798 samples from natural foci of plague were tested, using internal quality control multiple-polymerase chain reaction, F1 antigen marked by immuno chromatographic assay and enzyme linked immunosorbent assay. Culture of Yersinia pestis and reverse indirect hemagglutination assay were used as reference diagnostic methods.</p><p><b>RESULTS</b>The overall positive rate of culture on Yersinia pestis together with gene and antigen detection was 7.34%, showing an 16.81% increase when comparing to 6.28% using Yersinia pestis culture method alone. The rate of coincidence was 97.13%.</p><p><b>CONCLUSION</b>The new standard being used for specific gene and antigen detection could increase the positive rate of diagnosis on plague.</p>
Subject(s)
Animals , Mice , Bacterial Proteins , Genetics , Allergy and Immunology , Enzyme-Linked Immunosorbent Assay , Plague , Microbiology , Polymerase Chain Reaction , Yersinia pestis , Genetics , Allergy and Immunology , VirulenceABSTRACT
<p><b>OBJECTIVE</b>To study the distribution of genomovars and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau.</p><p><b>METHODS</b>Primer pairs targeting the twenty-two different regions(DFRs) were designed for detecting the presence or deletion of each DFR in 297 strains isolated from the Qinghai-Tibet Plateau.</p><p><b>RESULTS</b>9 genomovars, i. e. Genomovar 1, 5, 6, 7, 8, 10, 11, new type and Ype-ancestor were identified in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau. Among these genomovars, genomovar 5,8 and 10 were dominant types. The total rate of the three genomovars was 80.6% (204/253) and the genomovars in different regions were different. All of 44 strains of Y. pestis in the Microtus fuscus plague focus of the Qinghai-Tibet Plateau belonged to genomovar 14.</p><p><b>CONCLUSION</b>The distribution of genomovars of Y. pestis in the Qinghai-Tibet plateau had remarkable characteristics geographically. Based on the distribution of genomovars of Y. pestis, the routes of transmission and microevolution of Y. pestis were proposed.</p>