California state mosquito-borne virus surveillance and response plan: A retrospective evaluation using conditional simulations
California state mosquito-borne virus surveillance and response plan: A retrospective evaluation using conditional simulations
复制标题
DOI：
10.4269/ajtmh.2003.68.508
复制
发表时间：
2003-05-01
影响因子：
3.3
通讯作者：
Kramer, VL
中科院分区：
文献类型：
--
作者：
Barker, CM;Reisen, WK;Kramer, VL
加州蚊媒病毒监测和应对计划最近制定，以提供一种半定量的方法来评估西部马脑脊髓炎（WEE）或圣路易斯脑炎（SLE）病毒的风险，并在人类感染风险增加期间为蚊子控制和公共卫生机构提供干预指南。西尼罗河病毒最近已抵达加州，应对计划还将为评估人类和马感染该病毒的风险提供基线。在应对计划中，通过对以下因素造成的风险取平均值来计算总体风险：1）环境条件，2）成年蚊子媒介丰度，3）媒介感染率，4）哨兵鸡血清转化率，5）马病例（WEE），6）人类病例，7）病毒活动与人口稠密地区的接近程度。总体风险分为三个级别：正常季节，应急计划或流行病条件。我们使用加州几个地区WEE和SLE无、地方病和流行活动年份的历史数据评估了该应对计划，以确定计算的风险水平是否接近实际情况。考虑了两种病毒的多种风险计算方法。根据整个季节的累积温度，降雨量和径流水平评估的风险比仅基于前半个月的双周评估提供了更准确或同样准确的评估。对于WEE，在具有地方病活动的年份或具有WEE流行活动的年份的早期季节期间，将马和人的病例作为单一风险因素结合起来提高了模型预测待定WEE活动的能力，但是将这两个因素分开允许更好地指示WEE活动在流行病期间和没有活动的时期。对于SLE，在最近的所有研究期间，通过降雨和径流测量的干燥条件下的高风险分配产生了实际病毒活性的最准确的表示。
The California Mosquito-Borne Virus Surveillance and Response Plan recently was developed to provide a semi-quantitative means for assessing risk for western equine encephalomyelitis (WEE) or St. Louis encephalitis (SLE) viruses and to provide intervention guidelines for mosquito control and public health agencies during periods of heightened risk for human infection. West Nile virus recently has arrived in California, and the response plan also will provide a baseline for assessing the risk for human and equine infection with this virus. In the response plan, overall risk is calculated by averaging risk due to 1) environmental conditions, 2) adult mosquito vector abundance, 3) vector infection rates, 4) sentinel chicken seroconversion rates, 5) equine cases (for WEE), 6) human cases, and 7) the proximity of virus activity to populated areas. Overall risk is categorized into three levels: normal season, emergency planning, or epidemic conditions. We evaluated this response plan using historical data from years with no, enzootic, and epidemic activity of WEE and SLE in several areas of California to determine whether calculated risk levels approximated actual conditions. Multiple methods of risk calculation were considered for both viruses. Assessed risk based on cumulative temperature, rainfall, and runoff levels over the entire season provided more or equally accurate assessments than biweekly assessments based solely on the previous half-month. For WEE, during years with enzootic activity or earlyseason periods of years with WEE epidemic activity, combining horse and human cases as a single risk factor improved the model's ability to forecast pending WEE activity, but separating the two factors allowed a better indication of WEE activity during epidemics and periods with no activity. For SLE, assignment of higher risk to drier conditions as measured by rainfall and runoff yielded the most accurate representation of actual virus activity during all recent study periods.