基于广州市活禽批发市场不同禽类的市场链分析

为进一步了解广州市活禽批发市场不同种类活禽的来源、数量等情况,2015年对广州市全部6个活禽批发市场鸡、水禽(鸭、鹅)和珍禽(鸽子、鹌鹑、鹧鸪)的来源地、批次、数量等情况进行调查,并开展了活禽来源的空间分布、时间分布和时空分布等分析。结果发现:鸡是广州市活禽交易的主要活禽种类,而且来源广泛,涉及全国16个省122个地级市;水禽交易量巨大,来源省份主要为广东、广西、海南和江苏,其中鸭交易量远大于鹅;珍禽以鸽子为主,交易量相对较小,来源相对单一。总体而言,除第一季度(2月份)外,广州市各种活禽的交易时间均比较平稳,未出现明显的变化。本研究详细了解了本地区活禽批发市场的交易情况,为下一步以市场链为依据开展风险监测,更有针对性地采取基于风险的防控措施奠定了基础。     

广州市活禽批发市场禽流感病毒污染状况调查

[目的 ]了解广州市活禽批发市场禽流感病毒的污染情况,为广州市制定有针对性的防控措施提供技术支持。[方法 ]2015年2月—2016年1月,按照随机抽样原则,对广州市2个活禽批发市场进行调查,每月采集1次棉拭子样品(共3 090份),并对所采集的样品进行禽流感病毒荧光RT-PCR检测。[结果 ]在该期间内,2个活禽批发市场的样品禽流感总阳性率为52.50%(1 625/3 090);禽流感病毒检出阳性率较高的月份是4月和9—12月,较低的是6—8月;水禽的禽流感感染风险是鸡的1.6倍,环境中存在禽流感病毒的风险是鸡的1.39倍;各月份中,1月、3月、11月和12月环境样品的禽流感病毒阳性率显著高于家禽样品(P0.01),而6月份家禽样品的禽流感病毒阳性率显著高于环境样品(P0.01);来自广东省内(广州市除外)的活禽样品禽流感病毒阳性率最高,为49.31%,来自外省市的禽流感通用型阳性率最低,为31.43%(P0.01)。[结论 ]调查发现,广州市活禽批发市场的禽流感高发期为春夏及秋冬交替季节;活禽批发市场中的水禽和批发市场环境是禽流感病毒流行的关键危险因素。调查结果提示,今后要加强春夏和秋冬交替季节的禽流感防控工作,加强对批发市场水禽的禽流感防控和批发市场环境的清洗、消毒,以切实降低活禽批发市场的禽流感污染水平。     

广西边境地区活禽批发市场禽流感流行病学监测

为了给广西边境地区重大动物疫病防控阻截带建设提供数据支持,以及了解中越边境地区家禽禽流感病毒生态学,2012年12月—2017年12月,对广西边境地区主要活禽批发市场家禽及市场环境进行了系统监测。结果显示:广西边境地区活禽批发市场内禽流感病毒污染较重,呈多亚型病毒共存状态;家禽样品的平均病毒分离率为15.95%,环境样品则高达23.65%,明显高于家禽样品。市场调查发现:广西9个边境县(市、区)中,年活禽交易量在100万只以上的有5个;市场交易活禽主要为本地散养或规模场养殖家禽、从其他地区批发转运来的家禽以及边境走私家禽;大部分活禽市场没有配备消毒和无害化处理设施,也未严格执行休市制度。监测和调查结果表明,广西边境地区活禽批发市场家禽交易量大且频繁,来源复杂;市场中禽流感病毒污染严重,多亚型病毒在市场内常年蓄积循环,且存在家禽隐性带毒现象,因而有病毒散播风险。污染严重主要是因市场管理水平不高和生物安全措施不到位造成的,因此需要加强市场的动物卫生监管,提高禽流感监测力度。     

2020—2021年湖南省娄底市活禽批发市场市场链调查

为了解湖南省娄底市活禽批发市场活禽来源与流通情况,对2020—2021年娄底市2个活禽批发市场活禽调入、调出情况进行了调查.结果显示:每年调入娄底市活禽批发市场的活禽超过3000批次,数量超过600万羽;调入活禽种类有鸡、鸭、鹅、鸽等品种,其中活鸡比例超过80％;活禽批发市场主要以省内调入为主,还涉及12个省(自治区)...     

广州市活禽交易市场休市效果评估队列研究

[目的 ]了解目前广州市活禽交易市场每月休市一次(天)的实施效果,给人感染H7N9等流感病毒的科学防控提供技术依据。[方法 ]2015年3月,选择广州市某区1个活禽批发市场和2个活禽零售市场,分别于休市前、休市中,以及休市后的1、2、3、4、5、7、14、21和28天,采集市场内环境棉拭子和活禽口咽/泄殖腔棉拭子,共2 470份,进行通用型禽流感病毒荧光RT-PCR检测。[结果 ]研究发现,休市前、中、后各检测时点,环境样品中禽流感病毒阳性率分别为17.78%、10.00%、5.19%、29.63%、21.48%、22.96%、22.22%、45.93%、40.74%、47.41%和25.19%。虽然活禽交易市场在休市后禽流感病毒有非常明显的减少,但是阳性率在休市后第二天就开始显著升高,而且环境样品中病毒阳性率与活禽样品中病毒阳性率呈明显的统计学相关性(Pearson相关系数为0.82)。[结论 ]本研究是国内首次活禽交易市场(包括活禽批发市场和活禽零售市场)每月一次(天)休市效果的队列研究。研究显示,每月一次(天)的休市能迅速减少活禽交易市场内禽流感病毒的污染,但是随着市场的重新开放,感染禽流感病毒活禽的重新进入,市场内禽流感病毒阳性率再次迅速升高。推测仅仅依靠每月一次(天)的休市措施,无法从根本上降低本地区活禽交易市场内禽流感病毒的污染程度以及人感染禽流感的风险,需进一步调整防控策略,采取综合的防控措施。     

2018年广州市发现首例人H5N6感染后的活禽市场紧急流行病学调查

2018年9月30日卫生部门通报,从送检的1名重症肺炎患者标本中检出H5N 6流感病毒核酸阳性,且该患者有活禽接触史。为掌握关联区域内禽类H5亚型流感病毒分布情况,以便及时提出防控建议,采用现场调查与实验室检测相结合的方式,在与该人间感染病例有流行病学关联的农贸市场、活禽批发市场开展流行病学调查。结果显示:有流行病学关联的批发市场、农贸市场在临床巡查中均未发现禽类异常;在活禽批发市场和患者家附近的活禽零售市场,按照系统随机方法,分别采集10个和5个活禽交易档口的活禽咽/肛双拭子和环境棉拭子,均未检出H5亚型病毒核酸阳性。结果表明,H5亚型流感在广州市引发暴发性流行的风险较低,但需加强活禽市场的禽流感监测和市场监管,降低人类感染风险。     

广州市活禽批发市场活禽流感感染风险因素调查

为探究活禽进入广州市活禽批发市场前后的流感感染率动态变化及相关风险因素,从而为科学防控人感染H7N9流感提供依据,2017年4月,选择广州市2个活禽批发市场,于进场时和进场后24 h两个时间点,分别采集活禽口咽/泄殖腔棉拭子990份,采用荧光RT-PCR方法检测通用型流感病毒,同时以问卷方式,对有关流感传播风险因素进行调查。结果显示:2个活禽批发市场进场前后的活禽通用型流感病毒阳性率分别为24.24%和53.79%,活鸡、来自外省的活禽、档口清洗消毒频次小于1次/周等因素是活禽批发市场活禽感染流感的主要风险因素;Logistic回归拟合度较好(P0.05),ROC曲线下面积为0.659(95%CI:0.618~0.700)。结果表明:活禽从养殖场进入批发市场24 h后,通用型流感病毒阳性率明显上升,说明活禽市场助推了病毒的散播;外省活禽感染率高于本地活禽,提示应加强对外省活禽的流感监测;活禽档口的存栏密度及清洗消毒频次与活禽流感感染相关,因而应保持经营档口适当的活禽密度,并严格落实清洗消毒措施。     

基于禽流感病毒检测的活禽零售市场“零存栏”效果评估

[目的 ]评估活禽零售市场"零存栏"措施对禽流感的防控效果。[方法 ]选择广州市某区2个有代表性的活禽零售市场,相隔1周进行"零存栏"与非"零存栏"交替干预。整个研究为期4周,每周采集3天次相应的环境样品和活禽样品并进行通用型禽流感病毒荧光RT-PCR的检测。[结果 ]每周环境样品中禽流感病毒阳性率依次为50.7%、16.7%、35.3%和66.7%。"零存栏"与"非零存栏"期间环境样品禽流感病毒阳性率分别为41.67%和43.00%,没有统计学差异。[结论 ]本研究为国内首次较为系统地对目前活禽零售市场实施的"零存栏"措施进行评估的干预性流行病学调查。评估认为在本研究的框架下,活禽零售市场是否实施"零存栏"措施,对减少活禽零售市场禽流感病毒污染状况的作用不大,须采取降低家禽养殖场的禽流感病毒感染率、减少活禽在运输与交易(活禽批发市场等)环节的感染几率、杜绝活禽售卖等综合的防控措施。     

东兴市活禽市场禽流感流行病学调查

为掌握中越边境地区禽流感流行趋势,2013年10月～2020年10月对辖区内活禽销售市场进行系统监测。监测结果显示:活禽市场内常年都有病毒循环,呈多亚型病毒共存状态;环境样品的阳性率高达30.82%,家禽样品阳性率为20.77%。市场调查发现:东兴市的活禽销售市场规模不大而交易频繁;市场交易活禽主要来自本地小型养殖场、广西其他地区活禽交易批发市和规模养殖场以及边境走私家禽;活禽市场生物安全措施不到位,也未严格执行休市制度。监测和调查结果表明,东兴市活禽销售市场管理水平低,家禽来源复杂;市场环境污染严重,多种亚型禽流感病毒共存,且存在家禽隐性带毒现象,因而有病毒散播风险。因此需要加强禽流感监测力度,提高活禽市场的管理水平和生物安全措施。     

2013年广州市活禽农贸市场禽流感流行病学调查

[目的]了解广州市活禽农贸市场禽流感病毒的分布和流行情况,科学制定禽流感的防控措施,于2013年3-11月对广州市91个次的活禽农贸市场进行了禽流感监测,[方法]调查共采集了1064份活禽口咽/泄殖腔棉拭子和环境拭子,并用荧光RT-PCR方法进行了检测,[结果]发现通用型、H7N9和H9亚型禽流感阳性率分别为46.05%、0.09%和19.83%。其中,鸭棉拭子样品中通用型禽流感阳性率最高,达到了58.14%,其次为鸡棉拭子、鹅棉拭子和环境棉拭子样品,分别为46.28%、42.85%和35.19%;H9亚型禽流感阳性率最高的是鸡源样品,达到了28.88%,其次为鸭棉拭子和环境棉拭子样品,分别为12.56%和5.58%;仅从1份鸡棉拭子样品中检测到H7N9亚型禽流感病毒阳性。[结论]本次调查显示,广州地区活禽农贸市场存在较为严重的禽流感污染情况,需立即采取有效的防控措施以降低本地区发生禽流感以及人感染禽流感的风险。     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.