针对H9亚型禽流感HA基因保守序列设计引物,建立基于SYBR GreenⅠ检测模式的荧光定量RT-PCR（real-ti me RT-PCR,RRT-PCR）,最低检测限为8.33×102拷贝质粒DNA,与常规PCR相比,灵敏度高出100倍。扩增产物的熔解曲线分析只出现1个单特...针对H9亚型禽流感HA基因保守序列设计引物,建立基于SYBR GreenⅠ检测模式的荧光定量RT-PCR（real-ti me RT-PCR,RRT-PCR）,最低检测限为8.33×102拷贝质粒DNA,与常规PCR相比,灵敏度高出100倍。扩增产物的熔解曲线分析只出现1个单特异峰,无引物二聚体,Tm值为（83.83±0.22）℃,组内变异系数为0.52%~1.48%,组间变异系数为0.71%~2.21%,可重复性好;对H5亚型禽流感病毒、鸭肝炎病毒、鸭瘟病毒、鸭源禽1型副粘病毒无扩增;检测速度快,从样本处理到报告结果仅需4.5 h。展开更多
Infectious bursal disease(IBD)is an important contagious viral infection of immune system of poultry.This infection possesses a permanent threat to the profitability of poultry industry worldwide.The aim of this work ...Infectious bursal disease(IBD)is an important contagious viral infection of immune system of poultry.This infection possesses a permanent threat to the profitability of poultry industry worldwide.The aim of this work was to modify the Taq Man-MGB real-time reverse transcription-polymerase chain reaction(rRT-PCR)in one step involving two fluorogenic Taq Man labeled probe and using this protocol for detection of infectious bursal disease virus(IBDV)collected from suspected cases distributed in different regions of the country during the period 2013-2016.The intralaboratory validation of modified method was realized for specificity,linearity,repeatability,sensitivity and reproducibility.It allowed reducing the test running time by six folds.This method was applied on 102 pools of bursa of fabricius(BF)samples collected from affected broiler farms suspected to be infected by IBDV.Birds showing macroscopic lesions including muscle petechial hemorrhages,hypertrophy and hemorrhage of BF,were subjected to molecular analysis using modified protocol“Taq Man-MGB rRT-PCR”.The validation satisfied all criteria and the assay developed could be a useful tool for a very rapid diagnosis of IBDV and permit to detect and to discriminate in one-step very virulent(vv)from non-vv(classic and variant)IBDV strains.Out of 84 IBDV positive samples,a prevalence of 39%for vv strains and 61%for classical strains was noted.These results indicate that despite the vaccination against IBDV,the vv form of this pathologie continues to cause serious problems for Moroccan broiler chickens.The obtained results indicate the successfully detection of IBDV and differentiated all vvIBDV strains from non-vvIBDV strains;Avian infectious agent RNA viruses tested are negative,demonstrating great specificity of the assay.The results obtained indicate that this method is suitable as a routine laboratory test for the rapid detection and differentiation of IBDV strains in samples of avian origin.展开更多
<strong>Introduction:</strong> Coronavirus Disease 2019 (COVID-19) is an infectious respiratory disease caused by SARS-CoV-2. The disease was first broke out in Wuhan City, Hubei Province, China and subseq...<strong>Introduction:</strong> Coronavirus Disease 2019 (COVID-19) is an infectious respiratory disease caused by SARS-CoV-2. The disease was first broke out in Wuhan City, Hubei Province, China and subsequently spread to all countries and was considered by WHO as a worldwide pandemic. This study is aimed to determine the epidemiology of SARS-CoV-2 and the presence of UK variants in Zintan city of Libya taking some risk factors into account. <strong>Methods:</strong> In a cross-sectional retrospective study, a total of 15486 nasopharyngeal swabs were collected from COVID-19 suspected patients, travelers and people need disease-free certificates for hospital admission, etc. The samples were collected during the period from August 2020 to June 2021 and tested using real-time RT-PCR (rRT-PCR) kits for SARS-CoV-2 and UK variants. Age groups, sex, and monthly weather were considered as risk factors. <strong>Results:</strong> The positivity rate of COVID-19 in Zintan city was estimated to be (3891;25.12%) for the period from August 2020 to June 2021. Females showed significantly (p < 0.05) higher positivity rate (2100;54%) as compared to males (1791;46%). Out of the 3891 positive cases, 52 were deceased. The Case Fatality Rate (CFR) was 1.33 recorded significantly in cases aged ≥ 65 years which was higher in males (56.66%) than females (43.33%). The peak of the first wave of infection was recorded in October 2020 (590;15.15%) whereas the peak of the second wave of infection was recorded in April 2021 (727;18.71%). The positivity rate was decreased as the temperature increased. UK variant is detected firstly in May 2021 with the percentage of 6.2% of tested samples.<strong> Conclusions:</strong> Health Authorities are encouraged to continue implementing the control measures during the decrease phase of infection to stop transmission of the virus in the next wave. Early detection of new variants and studying their genetic characteristics play a valuable role in prevention and control.展开更多
文摘针对H9亚型禽流感HA基因保守序列设计引物,建立基于SYBR GreenⅠ检测模式的荧光定量RT-PCR（real-ti me RT-PCR,RRT-PCR）,最低检测限为8.33×102拷贝质粒DNA,与常规PCR相比,灵敏度高出100倍。扩增产物的熔解曲线分析只出现1个单特异峰,无引物二聚体,Tm值为（83.83±0.22）℃,组内变异系数为0.52%~1.48%,组间变异系数为0.71%~2.21%,可重复性好;对H5亚型禽流感病毒、鸭肝炎病毒、鸭瘟病毒、鸭源禽1型副粘病毒无扩增;检测速度快,从样本处理到报告结果仅需4.5 h。
文摘Infectious bursal disease(IBD)is an important contagious viral infection of immune system of poultry.This infection possesses a permanent threat to the profitability of poultry industry worldwide.The aim of this work was to modify the Taq Man-MGB real-time reverse transcription-polymerase chain reaction(rRT-PCR)in one step involving two fluorogenic Taq Man labeled probe and using this protocol for detection of infectious bursal disease virus(IBDV)collected from suspected cases distributed in different regions of the country during the period 2013-2016.The intralaboratory validation of modified method was realized for specificity,linearity,repeatability,sensitivity and reproducibility.It allowed reducing the test running time by six folds.This method was applied on 102 pools of bursa of fabricius(BF)samples collected from affected broiler farms suspected to be infected by IBDV.Birds showing macroscopic lesions including muscle petechial hemorrhages,hypertrophy and hemorrhage of BF,were subjected to molecular analysis using modified protocol“Taq Man-MGB rRT-PCR”.The validation satisfied all criteria and the assay developed could be a useful tool for a very rapid diagnosis of IBDV and permit to detect and to discriminate in one-step very virulent(vv)from non-vv(classic and variant)IBDV strains.Out of 84 IBDV positive samples,a prevalence of 39%for vv strains and 61%for classical strains was noted.These results indicate that despite the vaccination against IBDV,the vv form of this pathologie continues to cause serious problems for Moroccan broiler chickens.The obtained results indicate the successfully detection of IBDV and differentiated all vvIBDV strains from non-vvIBDV strains;Avian infectious agent RNA viruses tested are negative,demonstrating great specificity of the assay.The results obtained indicate that this method is suitable as a routine laboratory test for the rapid detection and differentiation of IBDV strains in samples of avian origin.
文摘<strong>Introduction:</strong> Coronavirus Disease 2019 (COVID-19) is an infectious respiratory disease caused by SARS-CoV-2. The disease was first broke out in Wuhan City, Hubei Province, China and subsequently spread to all countries and was considered by WHO as a worldwide pandemic. This study is aimed to determine the epidemiology of SARS-CoV-2 and the presence of UK variants in Zintan city of Libya taking some risk factors into account. <strong>Methods:</strong> In a cross-sectional retrospective study, a total of 15486 nasopharyngeal swabs were collected from COVID-19 suspected patients, travelers and people need disease-free certificates for hospital admission, etc. The samples were collected during the period from August 2020 to June 2021 and tested using real-time RT-PCR (rRT-PCR) kits for SARS-CoV-2 and UK variants. Age groups, sex, and monthly weather were considered as risk factors. <strong>Results:</strong> The positivity rate of COVID-19 in Zintan city was estimated to be (3891;25.12%) for the period from August 2020 to June 2021. Females showed significantly (p < 0.05) higher positivity rate (2100;54%) as compared to males (1791;46%). Out of the 3891 positive cases, 52 were deceased. The Case Fatality Rate (CFR) was 1.33 recorded significantly in cases aged ≥ 65 years which was higher in males (56.66%) than females (43.33%). The peak of the first wave of infection was recorded in October 2020 (590;15.15%) whereas the peak of the second wave of infection was recorded in April 2021 (727;18.71%). The positivity rate was decreased as the temperature increased. UK variant is detected firstly in May 2021 with the percentage of 6.2% of tested samples.<strong> Conclusions:</strong> Health Authorities are encouraged to continue implementing the control measures during the decrease phase of infection to stop transmission of the virus in the next wave. Early detection of new variants and studying their genetic characteristics play a valuable role in prevention and control.
