SPATIAL AND TEMPORAL DYNAMICS OF LEISHMANIA MEXICANS IN SOUTH TEXAS

德克萨斯州南部墨西哥利什曼原虫的时空动态

• 批准号: 6107795
• 负责人: SARA F KERR
• 金额: $ 12.22万
• 依托单位: UNIVERSITY OF THE INCARNATE WORD
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-02-01 至 2000-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6107795
• 关键词: Psychodidae; Rodentias; animal mortality; animal population density; climate; computer simulation; data collection; disease /disorder proneness /risk; disease reservoirs; electrophoresis; environment; epizootiology; field study; host organism interaction; leishmaniasis; longitudinal animal study; polymerase chain reaction; seasons; skin infection; tissue /cell culture; zoonosis

The proposed research is a three-year investigation of the zoonotic cycle of cutaneous leishmaniasis in Texas. The long term objective is understanding of the epidemiology of cutaneous leishmaniasis in the United States, including mechanism of transmission, human risk factors, and dynamics of the enzootic cycle. The study will test the following hypotheses: I. The southern plains woodrat (Neotoma micropus) is the reservoir of Leishmania mexicana in Texas. II. Lutzomyia anthophora is the vector among the woodrats. Ill. Change of prevalence of L. mexicana in N. micropus is highly correlated with change of abundance of the sand fly, L. anthophora. A trap-release-recapture study of a population of N. micropus will monitor the seasonal change in prevalence of L. mexicana at a focus where transmission to a human is known to have occurred and prevalence in the woodrats is 50%. Woodrats will be screened for Leishmania by culture in Schneider's Drosophila medium supplemented with fetal calf serum, and PCR. Isolates will be characterized by enzyme analysis. The density and spatial distribution of the woodrats will be mapped using a Geographic Positioning System and a Geographic Information System. Seasonal changes in density and spatial distribution will be monitored. Population characteristics that influence the role the woodrats play as a reservoir, including mortality, natality, sex ratio and sand flies and dispersal, will be studied. The density, spatial distribution, and sex ratio of sand flies (Lutzomyia sp) associated with the woodrats will be monitored bimonthly for three years, using light traps, funnel traps, sticky paper and aspirators. Sand flies will be screened for Leishmania. Wind speed, wind direction, temperature, relative humidity, atmospheric pressure and precipitation will be continually monitored and correlated with sand fly population dynamics. The temperature and relative humidity within rodent burrows will also be monitored, and environmental conditions in burrows from which sand flies have been collected will be compared with those from which no sand flies are collected. The correlation between sand fly abundance and prevalence of infection in the woodrats will be tested, as will the correspondence in spatial distribution between infected woodrats and areas of peak sand fly occurrence. A model of transmission of L. mexicana among N. micropus will be field tested.

拟议的研究是对人畜共患循环的为期三年的调查 德克萨斯州皮肤利什曼病。长期目标是 了解皮肤利什曼病的流行病学 美国，包括传播机制、人类风险因素、 和地方性动物循环的动态。该研究将测试以下内容 假设： I. 南部平原林鼠 (Neotoma micropus) 是 德克萨斯州墨西哥利什曼原虫水库。二.花斑螺是 林鼠中的向量。 III. 墨西哥乳杆菌流行率变化 N. micropus 与沙子丰度的变化高度相关 苍蝇，L. anthophora。对 N. 种群的诱捕-释放-再捕获研究。 micropus 将监测墨西哥乳杆菌流行的季节变化 在已知已发生向人类传播的焦点处，并且 林鼠中的患病率为 50%。林鼠将接受筛查 在施耐德果蝇培养基中培养利什曼原虫，并补充 胎牛血清和PCR。分离物将通过酶进行表征 分析。林鼠的密度和空间分布为 使用地理定位系统和地理信息绘制地图 系统。密度和空间分布的季节性变化将 被监控。影响角色的人口特征 林鼠充当储存库，包括死亡率、出生率、性别比 将研究白蛉及其传播。密度、空间 与白蛉 (Lutzomyia sp) 相关的分布和性别比例 将在三年内每两个月对林鼠进行一次光照监测 陷阱、漏斗陷阱、粘纸和吸气器。沙蝇将会 筛查利什曼原虫。风速、风向、温度、 相对湿度、大气压和降水量 持续监测并与白蛉种群动态相关。 啮齿动物洞穴内的温度和相对湿度也会 监测沙子飞出的洞穴的环境条件 收集到的将与没有沙蝇的进行比较 被收集。白蛉丰度与流行率之间的相关性 将测试林鼠的感染情况以及对应关系 受感染林鼠和尖沙区域之间的空间分布 蝇的发生。墨西哥乳杆菌在小猪笼草中的传播模型 将进行现场测试。