| Tuberculosis(TB)is known as an important zoonotic infectious disease since humans and animals can be cross-infected by Mycobacterium tuberculosis complex(MTBC)members,which poses a major global threat to the health of humans and many species of animals.The main members of MTBC include Mycobacterium tuberculosis(M.tb),Mycobacterium bovis(M.bovis),and Mycobacterium caprae(M.caprae).In May 2014,the World Health Assembly passed a resolution of the post-2015 End TB Strategy with its ambitious targets to be fully realized in 2035.However,the maintenance of MTBC infection in the multi-host system is a great barrier for achieving this goal worldwide.Currently,commercial detection methods including reagents and kits are mainly developed for bovine TB(BTB)and human TB,detection methods for other animals such as sheep,goats,cervids,monkeys,and some other wild animals are needed urgently.For the development of one universal ELISA to detection of MTBC infection,and investigate the epidemiological status of bovine,sheep and goats TB in China,our study:(1)Detection of MTBC infection by one universal ELISAA universal indirect ELISA was established for detecting Mycobacterium tuberculosis complex infection for multiple live hosts by using a fusion protein of MPB70,MPB83,ESAT6,and CFP10 common in M.tb,M.bovis,and M.caprae as the coating antigen(MMEC)and HRP-labeled fusion protein A and G as a secondary antibody.After testing the known positive and negative sera,the receiver operating characteristic curves were constructed to decide the cut-off values.Then,the diagnostic sensitivity and specificity of MMEC/AG-iELISA were determined as 100.00%(95% CI: 96.90%,100.00%)and 100.00%(95% CI: 98.44%,100.00%)for M.bovis infection of cattle,100.00%(95% CI: 95.00%,100.00%)and 100.0%(95% CI:96.80%,100.00%)for M.bovis infection of sheep,90.74%(95% CI: 80.09%,95.98%)and98.63%(95% CI: 95.14%,99.76%)for M.bovis infection of cervids,100.00%(95% CI:15.81%,100.00%)and 98.81%(95% CI: 93.54%,99.97%)for M.bovis infection of monkeys,100.00%(95% CI: 86.82%,100.00%)and 94.85%(95% CI: 91.22%,97.03%)for M.tb infection of humans.Furthermore,this MMEC/AG-iELISA likely detect M.caprae infection in roe deer.The sensitivity of MMEC/AG-iELISA to detect BTB,sheep TB,deer TB,and monkey TB were higher than the commercial kit.In addition,MMEC/AG-iELISA had excellent analytical specificity.(2)Cross-Sectional Survey on Nationwide Seroprevalence of BTB in ChinaDuring June 2018 to December 2020,5592 serum samples from 243 herds were randomly collected in China by multistage sampling strategy and tested with MMEC/AG-iELISA.The BTB prevalence at individual level was 3.84%(95% CI: 3.36%,4.38%),Southern China had the highest prevalence of 12.36%(95% CI: 8.72%,16.85%),Northeast China had the lowest prevalence of 0.44%(95% CI: 0.12%,1.13%).The BTB prevalence at herd level was 29.22%(95% CI: 23.58%,35.37%),Central China had the highest prevalence of 56.52%(95% CI:34.49%,76.81%),Northeast China had the lowest prevalence of 2.63%(95% CI: 0.07%,13.81%).In the multivariable logistic regression model at the individual level,the seroprevalence of Southern,Central,Northern,Eastern and Southwest China were significantly higher than that of Northwest China,OR were 15.26(95% CI: 5.31,43.86)(p < 0.01)、7.38(95% CI: 2.44,22.26)(p < 0.01)、7.56(95% CI: 2.68,21.33)(p < 0.01)、6.59(95% CI: 2.34,18.57)(p < 0.01),and 4.10(95% CI: 1.40,11.98)(p = 0.01),respectively.In addition,the seroprevalence of BTB in summer was significantly higher than that in winter,OR = 3.78(95%CI: 2.58,5.54)(p < 0.01).(3)Nationwide cross-sectional study on sheep and goats TB in ChinaDuring June 2019 to December 2020,2945 serum samples from 110 herds were randomly collected in China by multistage sampling strategy and tested with MMEC/AG-iELISA.The sheep and goats TB prevalence at individual level was 4.65%(95% CI: 3.92%,5.48%),Southwest China had the highest prevalence of 12.30%(95% CI: 9.18%,16.02%),Central China had the lowest prevalence of 0.37%(95% CI: 0.01%,2.05%).The sheep and goats TB prevalence at herd level was 32.73%(95% CI: 24.08%,42.33%),Northeast China had the highest prevalence of 55.56%(95% CI: 21.20%,86.30%),Central China had the lowest prevalence of 12.50%(95% CI: 0.32%,52.65%).In the multivariable logistic regression model at the individual level,the seroprevalence of Southwest,Southern,Northern and Northeast China were significantly higher than that of Central China,OR were 28.62(95% CI: 3.91,209.45)(p < 0.01)、22.65(95% CI: 3.01,170.78)(p < 0.01),14.21(95% CI: 1.92,104.95)(p < 0.01),and 10.85(95% CI: 1.40,84.41)(p = 0.02),respectively.In addition,the seroprevalence of sheep and goats TB in summer was significantly higher than that in winter,OR was 6.90(95% CI: 3.47,13.69)(p < 0.01).In conclusion,MMEC/AG-iELISA had a potential application in controlling TB and promoting the realization of the End-TB strategy,nationwide cross-sectional study on bovine,sheep and goats TB in China will provide data support for the designment of bovine,sheep and goats TB control strategy in China. |
PDF Full Text Request