在血吸虫病流行病学调查中，人们常常使用钉螺感染率及感染螺密度这两个反映感染螺水平的指标。但不少调查者往往把两者混淆起来而视为同一概念，导致错误结论，给防治决策带来不利的影响。为弄清两者的相互关系，本文结合现场调查资料分析如下。１材料和方法１．１现场选... In the epidemiological survey of schistosomiasis, people often use the snail infection rate and infection snail density, which reflect the index of infection snail level. However, many investigators often confuse the two with the same concept, leading to wrong conclusions and adversely affecting the prevention and control decision-making. To clarify the relationship between the two, this article combined with field survey data analysis is as follows. 1 materials and methods 1.1 site selection ...