Applied Epidemiology Research Papers/Topics

Modelling and manipulation of aphid-mediated spread of non-persistently transmitted viruses

Abstract: Aphids vector many plant viruses in a non-persistent manner i.e., virus particles bind loosely to the insect mouthparts (stylet). This means that acquisition of virus particles from infected plants, and inoculation of uninfected plants by viruliferous aphids, are rapid processes that require only brief probes of the plant’s epidermal cells. Virus infection alters plant biochemistry, which causes changes in emission of volatile organic compounds and altered accumulation of nutrien...

Occurrence and distribution of Nosema ceranae in honey bee colonies in the Comoros Islands

Abstract: Nosemosis is a parasitic disease caused by microsporidian pathogens of the genus Nosema infecting both the Western honey bee, Apis mellifera, and the Asian honey bee Apis cerana. The disease may adversely affect bee colonies and eventually result in high losses in apiculture and agriculture. We determined the Nosema species infecting honey bees and their prevalence in two islands of the Comoros Archipelago (Grande Comore (GCO) and Mohéli (MOH)) in the Southwest Indian Ocean. In Co...

A cross-sectional observational study investigating the association between sedges (swamp grasses, Cyperaceae) and the prevalence of immature malaria vectors in aquatic habitats along the sho

Abstract: Background: Strategies that involve manipulations of the odour-orientation of gravid malaria vectors could lead to novel attract-and-kill interventions. Recent work has highlighted the potential involvement of graminoid plants in luring vectors to oviposition sites. This study aimed to analyse the association between water-indicating graminoid plants (Cyperaceae, sedges), other abiotic and biotic factors and the presence and abundance of early instar Anopheles larvae in aquatic hab...

Competing risk events in antimalarial drug trials in uncomplicated Plasmodium falciparum malaria: a WorldWide Antimalarial Resistance Network individual participant data meta-analysis

Abstract: Background: Therapeutic efcacy studies in uncomplicated Plasmodium falciparum malaria are confounded by new infections, which constitute competing risk events since they can potentially preclude/pre-empt the detection of subsequent recrudescence of persistent, sub-microscopic primary infections. Methods: Antimalarial studies typically report the risk of recrudescence derived using the Kaplan–Meier (K–M) method, which considers new infections acquired during the follow-up period...

The Role of Unused Swimming Pools as a Habitat for Anopheles Immature Stages in Urban Malindi, Kenya

Abstract: ABSTRACT. We conducted larval surveys in habitats located in urban Malindi, Kenya, in 2005 and 2006 with the goal of determining the productivity of unused swimming pools in relation to other habitats. Of the 250 habitats sampled, 66 were unused swimming pools, 93 were wells, 60 were drainage troughs, and 31 were miscellaneous areas, such as septic tanks, swamps, concrete tanks, fish ponds, car-track depressions, and drainage ponds. Anopheles gambiae s.l. was the only anophelines s...

Estimating Dispersal and Survival of Anopheles gambiae and Anopheles funestus Along the Kenyan Coast by Using Mark–Release–Recapture Methods

Abstract: Mark-Drelease-Drecapture (MRR) experiments were conducted with emerging Anopheles gambiae s.l. and Anopheles funestus Giles at Jaribuni and Mtepeni in KiliÞ, along the Kenyan Coast. Of 739 and 1,246 Anopheles released at Jaribuni and Mtepeni, 24.6 and 4.33% were recaptured, respectively. The daily survival probability was 0.96 for An. funestus and 0.95 for An. gambiae in Jaribuni and 0.83 and 0.95, respectively, in Mtepeni. The maximum ßight distance recorded was 661 m. The high ...

Phlebotomus (Larroussius) orientalis (Diptera: Psychodidae) as a probable secondary vector of visceral leishmaniasis in Kenya

Abstract: According to the World Health Organization’s reports, leishmaniases in humans are caused by 20 species of protozoa, belonging to the genus Leishmania1.The parasites are transmitted by the bite of a female tiny, 2–3 mm long insect vector, the phlebotomine sandfly1. Leishmaniasis endemic areas in Kenya are—West Pokot, Kitui, Machakos, Meru,Koibatek and Kajiado districts2–6. Kala-azar (Visceral leishmaniasis) in these endemic sites is transmitted by Phlebotomus martini (Dipter...

Influence of Biological and Physicochemical Characteristics of Larval Habitats on the Body Size of Anopheles gambiae Mosquitoes (Diptera: Culicidae) along the Kenyan coast

Abstract: Background & objectives: The number and productivity of larval habitats ultimately determine the density of adult mosquitoes. The biological and physicochemical conditions at the larval habitat affect larval development hence affecting the adult body size. The influence of biological and physicochemical characteristics on the body size of Anopheles gambiae was assessed in Jaribuni village, Kilifi district along the Kenyan Coast. Methods: Ten cages measuring 1 × 1 × 1 m (1 m3) wi...

Evaluating the impact of larviciding with Bti and community education and mobilization as supplementary integrated vector management interventions for malaria control in Kenya and Ethiopia

Abstract: Background Malaria prevention in Africa is mainly through the use of long-lasting insecticide treated nets (LLINs). The objective of the study was to assess the effect of supplementing LLINs with either larviciding with Bacillus thuringiensis israelensis (Bti) or community education and mobilization (CEM), or with both interventions in the context of integrated vector management (IVM). Methods The study involved a factorial, cluster-randomized, controlled trial conducted in Malindi...

Blood-Feeding Patterns of Culex Quinquefasciatus and other Culicines and Implications for Disease Transmission in Mwea Rice Scheme, Kenya

Abstract: Studies were conducted in Mwea Rice Scheme, Kenya during the period April 2005 and January 2007 to determine the host-feeding pattern of culicine mosquitoes. Mosquitoes were collected indoors and outdoors and tested for human, bovine, goat, and donkey blood meals by an Enzyme-Linked Immunosorbent Assay. A total of 1,714 blood-engorged samples comprising Culex quinquefasciatus Say (96.1%), Culex annulioris Theobald (1.8%), Culex poicilipes Theobald (0.9%), Aedes cuminsi Theobald (1....

Genomic analysis reveals independent evolution of Plasmodium falciparum populations in Ethiopia

Abstract: Background:Plasmodium falciparum parasite populations in Ethiopia have been experiencing local selective pres‑sures from drugs and immunity, leading to evolutionary adaptation. However, there was a paucity of data on genomic characterization and evolutionary adaptations of P. falciparum isolates from the central area of Ethiopia.Methods:Whole‑genome analysis of 25 P. falciparum isolates from central Ethiopia, specifically from West Arsi, were studied to determine their genetic ...

Diversity and multiplicity of P. falciparum infections among asymptomatic school children in Mbita, western Kenya

Abstract: Multiplicity of infection (MOI) and genetic diversity of P. falciparum infections are important surrogate indicators for assessing malaria transmission intensity in different regions of endemicity. Determination of MOI and diversity of P. falciparum among asymptomatic carriers will enhance our understanding of parasite biology and transmission to mosquito vectors. This study examined the MOI and genetic diversity of P. falciparum parasite populations circulating in Mbita, a region ...

Anopheles rufipes implicated in malaria transmission both indoors and outdoors alongside Anopheles funestus and Anopheles arabiensis in rural south-east Zambia

Abstract: The primary malaria vector-control interventions, indoor residual spraying and long-lasting insecticidal nets, are effective against indoor biting and resting mosquito species. Consequently, outdoor biting and resting malaria vectors might elude the primary interventions and sustain malaria transmission. Varied vector biting and resting behaviour calls for robust entomological surveillance. This study investigated the bionomics of malaria vectors in rural south-east Zambia, focusin...

Biological traits of wild-caught populations of Aedes aegypti in dengue endemic and non-endemic regions of Kenya

Abstract: Variation in vector traits can modulate local scale differences in pathogen transmission. Here, we compared seasonal variation in the wing length (proxy for body size) and energy reserves of adult wild-caught Aedes aegypti populations from a dengue endemic (Kilifi) and non-endemic (Isiolo) area of Kenya. Vector sampling in the dengue endemic site was conducted during the dry and wet seasons. In the non-endemic area, it was limited to the dry season which characterizes this ecology ...

Tick-borne pathogens, including Crimean-Congo haemorrhagic fever virus, at livestock markets and slaughterhouses in western Kenya

Abstract: Vectors of emerging infectious diseases have expanded their distributional ranges in recent decades due to increased global travel, trade connectivity and climate change. Transboundary range shifts, arising from the continuous movement of humans and livestock across borders, are of particular disease control concern. Several tick-borne diseases are known to circulate between eastern Uganda and the western counties of Kenya, with one fatal case of Crimean-Congo haemorrhagic fever (C...


1 - 15 Of 16 Results