Abstract: Octenol (1-octen-3-ol), acetone, 4-methylphenol, 3-n-propylphenol, and other potential attractants (human urine, stable fly faeces), as well as guiacol, creosol (potential repellents), were tested as baits for biting flies in North America using standard phthalogen blue IF3GM cotton Nzi traps, or similar commercial polyester traps. Baits were tested during the summers of 2001 – 04 at a residence in Canada and during January – August 2001 at a dairy in the U.S.A. Behaviour in th...
Abstract: A better understanding of the oviposition behaviour of malaria vectors might facilitate development of new vector control tools. However, factors that guide aquatic habitat selection of gravid females is poorly understood. This study explored the relative attractiveness of similar artificial ponds (0.8 m2 ) aged at varying length prior to opening in such a way that wild Anopheles arabiensis could choose between ponds that were freshly set up, 4 or 17 days old to lay eggs. Physicoch...
Abstract: A possible malaria control approach involves the dissemination in mosquitoes of inherited symbiotic microbes to block Plasmodium transmission. However, in the Anopheles gambiae complex, the primary African vectors of malaria, there are limited reports of inherited symbionts that impair transmission. We show that a vertically transmitted microsporidian symbiont (Microsporidia MB) in the An. gambiae complex can impair Plasmodium transmission. Microsporidia MB is present at moderate p...
Abstract: Background: Management of arboviruses relies heavily on vector control. Implementation and sustenance of effective control measures requires regular surveillance of mosquito occurrences, species abundance and distribution. The current study evaluated larval habitat diversity and productivity, mosquito species diversity and distribution in selected sites along the coast of Kenya. Methods: A cross-sectional survey of mosquito breeding habitats, species diversity and distribution was ...
Abstract: Evolutionary fitness concepts dictate that blood parasites should regulate their transmission success by enhancing the responsiveness of arthropod vectors to infectious hosts. We observed that the presence of trophozoite stages of Plasmodium falciparum in peripheral blood, combined with clinical malaria symptoms, actually reduced the attractiveness to Anopheles gambiae mosquitoes of one Kenyan male, relative to another. Their innate levels of attractiveness were restored within day...
Abstract: The global rate of heavy metal pollution is rapidly increasing in various habitats. Anopheles malaria vector species (Diptera: Culicidae) appear to tolerate many aquatic habitats with metal pollutants, despite their normal proclivity for ‘clean’water (i.e. low levels of organic matter). Investigations were conducted to establish whether there are biological costs for tolerance to heavy metals in Anopheles gambiae Giles sensu stricto and to assess the potential impact of heavy m...
Abstract: The efficacy and persistence of 2 bacterial larvicides, Vectobac-DT (Bacillus thuringiensis israelensis [Bti]) and CulinexCombi (Bti and Bacillus sphaericus [Bs]), were tested against Anopheles gambiae and Culex quinquefasciatus in temporarily unused swimming pools with rainwater in Malindi, Kenya. Preand posttreatment larval densities were recorded by sampling with the standard WHO dipping technique for 8 consecutive days. The larvicides were applied to the pools with a knapsack s...
Abstract: Distribution of mosquito larvae in inundated rice fields is poorly known despite its profound implications in implementation of vector control programs. Based on oviposition behavior of gravid females and biotic and abiotic conditions of the rice field, distribution of mosquito larvae within the paddy may vary greatly. As a guide to implementation of mosquito vector control program targeting the aquatic stages in the rice fields in Mwea, studies were conducted to determine the dist...
Abstract: Background: Studies were conducted between April 2004 and February 2006 to determine the bloodfeeding pattern of Anopheles mosquitoes in Mwea Kenya. Methods: Samples were collected indoors by pyrethrum spay catch and outdoors by Centers for Disease Control light traps and processed for blood meal analysis by an Enzyme-linked Immunosorbent Assay. Results: A total of 3,333 blood-fed Anopheles mosquitoes representing four Anopheles species were collected and 2,796 of the samples were ...
Abstract: The bioecology of phlebotomine sand flies is intimately linked to the utilization of environmental resources including plant feeding. However, plant feeding behavior of sand flies remains largely understudied for Afrotropical species. Here, using a combination of biochemical, molecular, and chemical approaches, we decipher specific plant-feeding associations in field-collected sand flies from a dry ecology endemic for leishmaniasis in Kenya.Cold-anthrone test indicative of recent p...
Abstract: Visceral and cutaneous leishmaniasis are endemic to specific regions due to the ecological preferences of phlebotomine sand flies and Leishmania spp. transmission. Sand fly entomological data in northern Kenya are scarce due to limited studies and neglect of leishmaniasis. The aim of this study was to investigate: (i) sand fly diversity and distribution; (ii) occurrence of Leishmania DNA within sand flies; and (iii) blood-meal sources of sand flies in Laisamis, northern Kenya. We c...
Abstract: Editorial overview
Abstract: Aedes simpsoni complex has a wide distribution in Africa and comprises at least three described sub-species including the yellow fever virus (YFV) vector Ae. bromeliae. To date, the distribution and relative contributions of the sub-species and/or subpopulations including bionomic characteristics in relation to YF transmission dynamics remain poorly studied. In this study conducted in two areas with divergent ecosystems: peri-urban (coastal Rabai) and rural (Rift Valley Kerio Valle...