Rosenberg R, Andre R G, Somchit L
Department of Entomology, Walter Reed Army Institute of Research, Washington, DC.
Trans R Soc Trop Med Hyg. 1990 Jan-Feb;84(1):22-8. doi: 10.1016/0035-9203(90)90367-n.
Man-biting collections were made for 7 consecutive nights per month for 24 months at 2 sites in a Thai village regularly treated with DDT and fenitrothion yet hyperendemic for Plasmodium falciparum and P. vivax. Only Anopheles dirus was incriminated as a vector: 1.6% were infective and 2.4% were infected (median numbers of oocysts = 3.5). Transmission occurred within the village, which was located in groves of rubber and fruit trees, during the dry months of November to May only, when rates of parity (64%) and biting (2/man-night) were higher than during the monsoon (38% and 0.8%/man-night). Vectorial capacity and inoculation rates surged and then fell during 30 d at the end of the monsoon, quickly reinitiating transmission. Sporozoite species were identified using indirect fluorescent antibody tests or enzyme-linked immunosorbent assays: 76% were P. falciparum, compared to 78% of gametocytes; one mosquito was infected with both species. Vector survival and inoculation rates differed between similar sites 800 m apart. Dry season breeding occurred at the bottom of a deep, concrete-lined well. Much of the natural forest habitat of An. dirus in south-eastern Thailand that was once destroyed for farming is now being replaced with orchards; this ecological change may reintroduce malaria to a wide area.
在泰国一个村庄的两个地点，连续24个月每月进行7个连续夜晚的人叮咬采集。该村庄定期使用滴滴涕和杀螟硫磷进行处理，但恶性疟原虫和间日疟原虫的流行率仍然很高。只有大劣按蚊被确认为传播媒介：1.6%具有感染性，2.4%被感染（卵囊中位数 = 3.5）。传播仅发生在位于橡胶林和果树林中的村庄内，仅在11月至5月的旱季，此时孕卵率（64%）和叮咬率（2次/人·夜）高于季风季节（38%和0.8%/人·夜）。在季风季节结束时的30天内，传播能力和接种率先上升后下降，随后迅速重新开始传播。使用间接荧光抗体试验或酶联免疫吸附测定法鉴定子孢子种类：76%为恶性疟原虫，而配子体为78%；一只蚊子同时感染了这两种疟原虫。相距800米的类似地点之间，媒介生存率和接种率有所不同。旱季繁殖发生在一口深的、衬砌混凝土的井底。泰国东南部大劣按蚊曾经因农业开垦而被破坏的许多天然森林栖息地，现在正被果园取代；这种生态变化可能会使疟疾在广大地区重新出现。
