Beier M S, Davis J R, Pumpuni C B, Noden B H, Beier J C
Department of Medicine, University of Maryland School of Medicine, Baltimore.
Am J Trop Med Hyg. 1992 Aug;47(2):195-200. doi: 10.4269/ajtmh.1992.47.195.
We investigated the process of sporozoite transmission during blood feeding for Anopheles gambiae and An. stephensi experimentally infected with Plasmodium falciparum. When infective mosquitoes were fed 22-25 days postinfection on an anesthetized rat, sporozoites were detected in the midgut of 96.5% of 57 An. gambiae (geometric mean [GM] = 32.5, range 3-374) and in 96.2% of 26 An. stephensi (GM = 19.5, range 1-345). There were no significant differences between species either in salivary gland sporozoite loads or in the number of ingested sporozoites. There was a significant linear relationship between sporozoite loads and the numbers of ingested sporozoites for both An. gambiae (r = 0.38) and An. stephensi (r = 0.69). Subsequently, An. gambiae were tested for sporozoite transmission by allowing them to feed individually on a suspended capillary tube containing 10 microliters of blood. A total of 83.3% of 18 infective mosquitoes transmitted a GM of 5.9 (range 1-36) sporozoites. The same mosquitoes contained a GM of 23.4 (range 2-165) ingested sporozoites. The number of ingested sporozoites was related to sporozoite loads (r = 0.42) but not to the number of sporozoites ejected into capillary tubes. Ingested sporozoites remained in the midgut up to 10 hr after feeding. The comparable numbers of sporozoites ingested by infective mosquitoes in both experiments indicates that the actual number of sporozoites transmitted to the vertebrate host during blood feeding is significantly reduced by the blood ingestion process.(ABSTRACT TRUNCATED AT 250 WORDS)
我们研究了感染恶性疟原虫的冈比亚按蚊和斯氏按蚊在吸血过程中的子孢子传播过程。当感染后的蚊子在感染后22 - 25天叮咬一只麻醉的大鼠时，在57只冈比亚按蚊的中肠中检测到子孢子的占96.5%（几何平均数[GM]=32.5，范围3 - 374），在26只斯氏按蚊的中肠中检测到子孢子的占96.2%（GM = 19.5，范围1 - 345）。在唾液腺子孢子载量或摄入子孢子数量方面，两种按蚊之间没有显著差异。对于冈比亚按蚊（r = 0.38）和斯氏按蚊（r = 0.69），子孢子载量与摄入子孢子数量之间均存在显著的线性关系。随后，让冈比亚按蚊逐个叮咬一根装有10微升血液的悬浮毛细管，以测试子孢子传播情况。18只感染蚊子中有83.3%传播了几何平均数为5.9（范围1 - 36）的子孢子。同样这些蚊子摄入子孢子的几何平均数为23.4（范围2 - 165）。摄入子孢子的数量与子孢子载量相关（r = 0.42），但与排入毛细管的子孢子数量无关。摄入的子孢子在进食后长达10小时仍留在中肠。两个实验中感染蚊子摄入的子孢子数量相当，这表明在吸血过程中实际传播到脊椎动物宿主的子孢子数量因吸血过程而显著减少。（摘要截短至250字）
