Wang P, Wang F, Sun Y, Wang J, Kou J, Huang Y, Kang X, Wan G, Liang Y, Wang Q
Shandong Institute of Parasitic Diseases, Jining, China.
Chin Med J (Engl). 1998 Mar;111(3):261-4.
To elucidate the transmission dynamic and epidemic trend of bancroftian filariasis occurred under the condition with no control measure taken 5 years after elimination of filariasis.
A 10-year longitudinal observation (from 1984 to 1994) was made in Huayuan Village in Shengli Township of Tancheng County, which used to be a high bancroftian filariasis-endemic area in southern part of Shandong Province.
The microfilarial rate decreased from 0.56% before the study to 0.12% after the study and 8 out of the 9 previous microfilaria-positive cases became negative gradually. During the study period, 6 new microfilaremia cases were detected, 5 of which became negative naturally within 3 to 4 years. Eighty-eight point eight nine per cent of the detected patients with microfilaremia converted into IgG4-negative after 10 years. The natural infective rate of vectors decreased year by year and became zero by the tenth year of the study, the annual transmission potency decreased also from 3.47 to zero by the tenth year.
It showed that under the local natural environment the biting rate representing the vector density which was obtained by capture method was from 24.1 to 52.5 person/night among the residents who did not use mosquito nets, and 13.5 to 21 person/night among the residents who used mosquito nets. The microfilarial rate of 0.56% in population with the average microfilarial density of 6.6 to 20.7 capita/60 microliters ear blood of residual microfilaria-positive patients might be considered as the terminal threshold of transmission.
阐明在丝虫病消除5年后未采取控制措施情况下班氏丝虫病的传播动态和流行趋势。
对山东省南部曾是班氏丝虫病高度流行区的郯城县胜利乡花园村进行了10年（1984年至1994年）的纵向观察。
微丝蚴率从研究前的0.56%降至研究后的0.12%，原来9例微丝蚴阳性病例中有8例逐渐转为阴性。研究期间，检测到6例新的微丝蚴血症病例，其中5例在3至4年内自然转阴。检测到的微丝蚴血症患者中有88.89%在10年后转为IgG4阴性。媒介的自然感染率逐年下降，到研究的第10年降为零，年传播势能也从3.47降至第10年的零。
结果表明，在当地自然环境下，用捕捉法得到的代表媒介密度的叮咬率，在未使用蚊帐的居民中为24.1至52.5人/夜，在使用蚊帐的居民中为13.5至21人/夜。残留微丝蚴阳性患者的人群微丝蚴率为0.56%，平均微丝蚴密度为6.6至20.7条/60微升耳血，可被视为传播的终末阈值。
