澜沧江下游航运区疟疾学调查

Investigation of the prevalent status of malaria in lower reaches of Lanchangjiang .

目的 了解澜沧江下游航运区疟疾流行情况和恶性疟原虫对氯喹、青蒿琥酯的敏感性。 方法 居民带虫普查、IFA检测、疟史访问、发热病人血检、媒介按蚊、社会经济等调查和恶性疟原虫对氯喹、青蒿琥酯敏感性测试。 结果 各种人群累计平均疟原虫率为8.36％(226／2 704),其中间日疟占58.85％,恶性疟占40.27％,混合疟占0.88％。发热病人疟原虫检出率为30.03％(106／353)。居民、搬运工人和船员的疟史率,2001年分别为38.39％、8.82％和1.06％。主要媒介微小按蚊占捕获10种244.只按蚊总数的10.66％,叮人率为0.75只／人工·h。恶性疟原虫对青蒿琥酯和氯喹的抗性率各为8.70％和96.15％;半数抑制量(ID50)分别为13.44和91.25nmoL／L。 结论 目前澜沧江下游航运区疟疾呈不同程度流行状态,防治工作薄弱,急待加强。氯喹仍不宜治疗恶性疟,青蒿琥酯的敏感性有所下降,应引起重视。

Objective To understand current malarial situation in the shipping area of Lanchangjiang River Downstream by investigation of annual malaria parasite carrying rate in the inhabitants, antibody level, in vitro sensitivity of malaria parasite to chloro-quine and artesunate. Methods Investigation of annual malaria parasite carrying rate, IFAT, malaria history, blood examination of feverish patients, vector Anopheline mosquitoes, social economics and the sensitivity of Plasmodium falciparum to chloroquine and artesunate were carried out. Results The average cumulated parasite carrying rate in different populations was 8.36% (2267 2 704) of which Plasmodium vivax , plasmodium falciparum and mixed infections accounted for 58.5% , 40.27% and 0.88% , respectively. The rate of malaria parasite detected from feverish patients was 30.03% (106/353) .Malaria history rates in inhabitants, porters and seamen in 2001 were 38.39% , 8.82% and 1.06% , respectively. A total of 244 mosquitoes belong to 10 species were captured and An. Minimus accounted for 10.66% of the total with a man-biting rate of 0.75/man.hour. The resistant rates of Plas-modium falciparum to choloroquine and artesunate were 96.15% and8.70%. with a ID50 of 13.44 and 91.25nmol/L, respectively. Conclusion At present, Malaria is still prevalent at various degrees in Lanchangjiang River Downstream shipping area and the control work is weak and needs to be strengthened. Chloroquine is not recommended for treatment of falciparum malaria and attention be given to the decrease of sensitivity of plasmodium falciparum to artesunate.