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Malaria sporozoites must invade the salivary glands of mosquitoes for maturation before transmission to vertebrate hosts. The duration of the sporogonic cycle within the mosquitoes ranges from 10 to 21 days depending on the parasite species and temperature. During blood feeding salivary gland proteins are injected into the vertebrate host, along with malaria sporozoites in the case of an infected mosquito. To identify salivary gland proteins depleted after blood feeding of female Anopheles campestris-like, a potential malaria vector of Plasmodium vivax in Thailand, two-dimensional gel electrophoresis and nano-liquid chromatography-mass spectrometry techniques were used. Results showed that 19 major proteins were significantly depleted in three to four day-old mosquitoes fed on a first blood meal. For the mosquitoes fed the second blood meal on day 14 after the first blood meal, 14 major proteins were significantly decreased in amount. The significantly depleted proteins in both groups included apyrase, 5′-nucleotidase/apyrase, D7, D7-related 1, short form D7r1, gSG6, anti-platelet protein, serine/threonine-protein kinase rio3, putative sil1, cyclophilin A, hypothetical protein Phum_PHUM512530, AGAP007618-PA, and two non-significant hit proteins. To our knowledge, this study presents for the first time the salivary gland proteins that are involved in the second blood feeding on the day corresponding to the transmission period of the sporozoites to new mammalian hosts. This information serves as a basis for future work concerning the possible role of these proteins in the parasite transmission and the physiological processes that occur during the blood feeding. [ABSTRACT FROM AUTHOR]

Background: Leishmaniasis is an emerging disease in Thailand with an unknown incidence or prevalence. Although the number of properly characterized and clinically confirmed cases is about 20, it is suspected that this low number masks a potentially high prevalence, with clinical disease typically manifesting itself against an immunocompromised background, but with a substantial number of subclinical or cured cases of infection. To date leishmaniasis in Thailand has been mainly ascribed to two taxa within the recently erected subgenus Mundinia Shaw, Camargo & Teixeira, 2016, Leishmania (Mundinia) martiniquensis Desbois, Pratlong & Dedet, 2014 and a species that has not been formally described prior to this study. Results: A case of simple cutaneous leishmaniasis was diagnosed in a patient from Nan Province, Thailand. Molecular analysis of parasites derived from a biopsy sample revealed this to be a new species of Leishmania Ross, 1908, which has been named as Leishmania (Mundinia) orientalis Bates & Jariyapan n. sp. A formal description is provided, and this new taxon supercedes some isolates from the invalid taxon "Leishmania siamensis". A summary of all known cases of leishmaniasis with a corrected species identification is provided. Conclusions: Three species of parasites are now known to cause leishmaniasis is Thailand, L. martiniquensis and L. orientalis n. sp. in the subgenus Mundinia, which contains the type-species Leishmania enriettii Muniz & Medina, 1948, and a single case of Leishmania infantum Nicolle, 1908. This study now enables epidemiological and other investigations into the biology of these unusual parasites to be conducted. It is recommended that the use of the taxonomically invalid name "L. siamensis" should be discontinued. [ABSTRACT FROM AUTHOR]

The ultrastructure of the midgut of fourth instar Ochlerotatus togoi was investigated by light, scanning and transmission electron microscopy. This study was performed to provide information to help devise future control efforts aimed at the larval stages of this vector of filariasis. The fourth instar midgut was approximately 2 mm in length and consisted of three morphologically distinct cell types: epithelial, regenerative, and endocrine cells. There was a monolayer of epithelial cells on the luminal surface of the midgut, with multiple folds of the plasma membrane where it adjoined the basement membrane. Regenerative cells were scattered throughout the basal portion of the epithelium, along with endocrine cells. No evidence of division or differentiation was seen in any of the cell types. Six layers of the peritrophic matrix were observed in the gut lumen which separated ingested food from the midgut epithelial cells. Cytoplasmic protrusions were seen in many areas of the luminal midgut surface and numerous autophagosomes were seen in the epithelial cells of both early and late fourth instar larvae, suggesting autophagy is involved in the degeneration process of the midgut in preparation for pupation. This study provides a basis for understanding normal Oc. togoi larval midgut development. Further studies are needed to determine the factors that control larval growth and the nutritional state. Such information could be used to reduce adult fecundity and develop biological control mechanisms.