摘要
在浙江、河南等１１个省、自治区选择经过海群生防治、丝虫和蚊媒种类有代表性的地方建点２１个，不采取防治措施，纵向观察３－５年。主要结果：①２７９例残存微丝蚴血症者大部陆续自然转阴；②微丝蚴率，２０个点逐年下降，１个点徘徊在原水平；③１２个点的蚊媒已未查见幼丝虫。结果表明，在以人饵蚊帐诱捕法调查，蚊媒叮人率为２０－５０只／人、夜，和有４０％左右居民合理使用蚊帐防蚊的情况下，２０个点的微丝蚴率，班氏丝虫病点≤１．７１％，马来丝虫病点≤１．５５％，残存微丝蚴血症者６０μｌ血平均密度大多在３－１０条，只有个别的密度较高，丝虫病的传播处于阈值以下，趋于阻断；１个徘徊于原水平的马来丝虫病点，微丝蚴率为２．３１％，有１例微丝蚴血症者密度较高（５４条／６０μｌ），处于丝虫病传播临界水平。
Twenty one villages from ten provinces and one autonomous region with different mf rates in population and different levels of mean mf density per 60 μl blood in positive cases and representative species of filaria and vector after DEC treatment were selected as study sites.In these villages a longitudinal investigation for a period of 3-5 years was carried out without adopting any control measure.The main results were:1.Among 279 residual microfilaremia cases,235 (84.2%) turned negative spontaneously and successively.The negative conversion rates were 86.6% (46/53) in malayan cases,60.8%(28/46) in bancroftian cases after 3 years’ follow up, and 100% (29 /29) in malayan cases, 87.4% (132/151) in bancraftian cases after 4 5 years follow up. Among 110 bancroftian cases followed up to seven years,109(99.1%)turned negative.2.Twenty two new microfilaremia cases were detected,of which,18 might be missed in previous blood examination,4 might be new infection.3. Mf rate in the population in twenty villages has been trending down,whereas in one village fluctuated around the original level.Among the 20 villages,no microfilaremia case was found in 7 villages.4. The natural infection rates of filarial larvae and infective rates in mosquito vectors were in descending trend in most of these villages,and no filarial larva was found in 12 villages.It was demonstrated that under these circumstances where the man-biting rate of mosquito vectors was within 20-50 mosquito per person and night by using the method of human bait bed net trapping, and about 40% of the population used bed-net reasonably,the mf rates in the 20 study villages were found to be ≤1.71% in areas of bancroftian filariasis,≤1.55%in areas of malayan filariasis and the mean mf density of residual microfilaremia cases in most villages was 3-10 mf per 60 μl blood,moderate mf density was found only in individual case,filariasis transmission has already been brought down below the threshold,and tended to be interrupted.In one village of malayan filariasis,the mf rate in population was 2.31% and there was one case of microfilaremia with density of 54mf/60 μl,filariasis transmission was at the critical level.
出处
《中国寄生虫学与寄生虫病杂志》
CAS
CSCD
北大核心
1994年第1期1-6,共6页
Chinese Journal of Parasitology and Parasitic Diseases
关键词
传播阈值
丝虫病
马来丝虫病
Transmission threshold,bancroftian filariasis,malayan filariasis,low density microfilaremia cases,longitudinal investigation
