Susceptibility of the Mosquitoes <I>Anopheles minimus, An. sinensis,</I> and <I>An. saperoi</I> (Diptera: Culicidae) from the Ryukyu Archipelago, Japan, to the Rodent Malaria <I>Plasmodium yoelii nigeriense</I>

Abstract

The susceptibility of three anopheline mosquitoes, Anopheles minimus Theobald, An. sinensis Wiedemann, and An. saperoi Bohart & Ingram, from the Ryukyu Archipelago to the rodent malaria, Plasmodium yoelii nigeriense was examined to find new vectors other than An. stephensi Liston for rodent malaria studies in the laboratory. The survival rate of the mosquitoes after feeding on mice infected with P. y. nigeriense was also examined. The Beech strain of An. stephensi from India was compared with An. minimus from Ishigaki Island, and An. sinensis and An. saperoi from Okinawa Island. Oocysts were first found on day 3 after feeding on mice infected with P. y. nigeriense in An. stephensi, on day 4 in An. minimus and An. saperoi, and day 6 in An. sinensis. From 8 to 14 d after feeding on malaria-positive mice, oocysts were present in 97.2-100% of An. stephensi, 85.7-100% of An. saperoi, 20-74.1% of An. minimus, and 12.5-13.3% of An. sinensis. The duration of oocyst occurrence in An. saperoi was 55 d, the longest among the anopheline mosquitoes used in this study. On day 8 after feeding, sporozoites were found in the salivary glands and heads of all the mosquitoes tested. From the 10th to 16th d, sporozoites were present in the salivary glands of 14.9% (range, 9.1-28.0%) of An. minimus, 47.3% (40.7-58.1) of An. saperoi, and 96.2% (94.1-97.2) of An. stephensi, but were absent in An. sinensis. Anopheles saperoi could be an excellent vector of P. y. nigeriense because it has comparatively high susceptibility and high longevity even after feeding on infected mice.

De novo transcriptome sequencing and sequence analysis of the malaria vector Anopheles sinensis (Diptera: Culicidae)

“…The Anopheles sinensis Wiedemann is a major malaria vector in China and other southeastern Asia countries with wide distribution from Afghanistan to northern China, Korea, Japan, Taiwan, and southward into western Indonesia [1-5]. An investigation of mosquito abundance in Yancheng, Jiangsu, China showed that An.…”

Molecular interactions betweenPlasmodiumand its insect vectors

“…55 days: P. yoelii in An. saperoi (Toma et al., 2002)], yet at the time the sporozoites invade the glands the mosquitoes reportedly mount a significant immune response (transcription of ICHIT, IGALE20, GNBP and defensin is upregulated) (Dimopoulos et al., 2001). Reconciling these observations requires the conclusion either that the response is sustained for such a brief period that the invading sporozoite survives the ineffectual attack; that the sporozoite is insusceptible to the responses mounted, or as has been shown, key lethal immune factors, e.g.…”