Browsing by Author "Angwech, Harriet"

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    Apparent density, trypanosome infection rates and host preference of tsetse flies in the sleeping sickness endemic focus of northwestern Uganda
    (BMC Veterinary Research, 2021) Opiro, Robert; Opoke, Robert; Angwech, Harriet; Nakafu, Esther; Oloya, Francis A.; Openy, Geoffrey; Njahira, Moses; Macharia, Mercy; Echodu, Richard; Malinga, Geoffrey M.
    African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies. Methodology: We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, trypanosome infection status and blood meal sources of tsetse flies. A subset (272) of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results: We captured a total of 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females) in the two districts with apparent density (AD) ranging from 0.6 to 3.7 flies/trap/day (FTD). 10.7% (29/272) of the flies were infected with one or more trypanosome species. Infection rate was not significantly associated with district of origin (Generalized linear model (GLM), χ2 = 0.018, P = 0.895, df = 1, n = 272) and sex of the fly (χ2 = 1.723, P = 0.189, df = 1, n = 272). However, trypanosome infection was highly significantly associated with the fly’s age based on wing fray category (χ2 = 22.374, P < 0.001, df = 1, n = 272), being higher among the very old than the young tsetse. Nested PCR revealed several species of trypanosomes: T. vivax (6.62%), T. congolense (2.57%), T. brucei and T. simiae each at 0.73%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusios chapini) and the African Savanna elephant (Loxodonta africana). Conclusion: We found an infection rate of 10.8% in the tsetse sampled, with all infections attributed to trypanosome species that are causative agents for AAT. However, more verification of this finding using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of control interventions.
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    Ethnobotanical survey of plants used as repellents against housefly, Musca domestica L. (Diptera: Muscidae) in Budondo Subcounty, Jinja District, Uganda
    (Journal of ethnobiology and ethnomedicine, 2018) Baana, Kalori; Angwech, Harriet; Malinga, Geoffrey Maxwell
    The housefly, Musca domestica L., is a major public health and domestic pest that spoils food and causes irritation and is a vector of many infectious disease pathogens of medical and veterinary importance. Currently, its control relies largely on chemical pesticides. However, the adverse health and environmental effects of pesticides, risk of development of insect resistance, and bioaccumulation through the food chain emphasize the need to search for environmentally friendly alternatives. This study aimed at documenting traditional knowledge about plants used as repellents against the houseflies by the people of Budondo Subcounty, Uganda. Methods: An ethnobotanical survey was conducted between November 2016 and June 2017. A total of 372 household members were interviewed on knowledge and use of traditional insect repellents, through face-toface interviews guided by semi-structured questionnaires administered in nine villages in Budondo Subcounty. Results: Overall, only 24.5% of the respondents had ample knowledge about insect repellent plants. A chi-square analysis shows a significant association between respondents’ knowledge of insect repellent plants and age, educational status, occupation, religion, and marital status although not with gender. Overall, eight plants from seven families and eight genera were mentioned as repellents. The growth forms encountered were tree, shrub, and herb. Plants that were commonly mentioned by respondents were Cupressus sempervirens L. (16.9%), followed by Lantana camara L.(16.1%), Eucalyptus globulus Labill. (11.0%), Carica papaya L. (8.6%), Cymbopogon citratus (de Candolle) Stapf (4.3%), Mentha × piperita L. (2.4%), Azadirachta indica A. Juss (2.2%), and Ocimum kilimandscharicum Gürke (0.8%) in descending order. Leaves were the most commonly used plant part (76.9%), followed by the stem/bark (19.8%), flowers (2.2%), and root (1.1%). Burning of the plant materials in order to generate smoke was the most popular method of application. Conclusions: This study has shown that there are many locally available plants in use by the people of Budondo Subcounty with potency for repelling houseflies. Further studies are needed to identify bioactive compounds responsible for the repellent activity in the different species which could be promoted as sustainable housefly control tools in these remotely located communities of Budondo. Furthermore, studies on the efficacy of these repellent plants or plant parts and their potential toxicological properties should be considered a priority.
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    Heterogeneity in the prevalence and intensity of bovine trypanosomiasis in the districts of Amuru and Nwoya, Northern Uganda
    (BMC veterinary research, 2015) Angwech, Harriet; Nyeko, Jack H. P.; Opiyo, Elizabeth A.; Okello-Onen, Joseph; Opiro, Robert; Echodu, Richard; Malinga, Geoffrey M.; Njahira, Moses N.; Skilton, Robert A.
    Livestock trypanosomiasis, transmitted mainly by tsetse flies of the genus Glossina is a major constraint to livestock health and productivity in the sub-Saharan Africa. Knowledge of the prevalence and intensity of trypanosomiasis is important in understanding the epidemiology of the disease. The objectives of this study were to (a) assess the prevalence and intensity of trypanosome infections in cattle, and (b) to investigate the reasons for the heterogeneity of the disease in the tsetse infested districts of Amuru and Nwoya, northern Uganda. Methods: A cross-sectional study was conducted from September, 2011 to January, 2012. Blood samples were collected from 816 cattle following jugular vein puncture, and screened for trypanosomes by HCT and ITS-PCR. A Pearson chi-squared test and logistic regression analyses were performed to determine the association between location, age, sex, and prevalence of trypanosome infections. Results: Out of the 816 blood samples examined, 178 (22 %) and 338 (41 %) tested positive for trypanosomiasis by HCT and ITS-PCR, respectively. Trypanosoma vivax infection accounted for 77 % of infections detected by ITS-PCR, T. congolense (16 %), T. brucei s.l (4 %) and mixed (T. vivax/ T. congolense/T.brucei) infections (3 %). The risk of trypanosome infection was significantly associated with cattle age (χ2 = 220.4, df = 3, P < 0.001). The highest proportions of infected animals were adult males (26.7 %) and the least infected were the less than one year old calves (2.0 %). In addition, the risk of trypanosome infection was significantly associated with sex (χ2 = 16.64, df=1, P < 0.001), and males had a significantly higher prevalence of infections (26.8 %) than females (14.6 %). Conclusion: Our results indicate that the prevalence and intensity of trypanosome infections are highly heterogeneous being associated with cattle age, location and sex.
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    Identification of Schistosoma mansoni eggs and other soil transmitted intestinal parasites in stool using Odongo-Aginya method
    (Research Square, 2019) Byagamy, John Paul; Malinga, Geoffrey Maxwell; Angwech, Harriet; Echodu, Richard; Igwaro Odongo-Aginya, Emmanuel
    Objective World Health Organisation recommends Kato-Katz technique for quantitative diagnosis of Schistosoma mansoni and other soil transmitted intestinal parasites in field research. However, for better visibility especially in hard stool specimens, the prepared slides in Kato-Katz technique are mostly examined after 1-2 hours. This longer clearing time over clear the eggs of parasites with thin cell walls in glycerine and morphology of the eggs are not often preserved in Kato-Katz method. These disadvantages are overcome using Odongo-Aginya method as illustrated by parasite eggs in the results. Result The Odongo-Aginya method uses compound stains of 7.5% nigrosin in 10% formalin and 0.5% eosin yellow in 10% formalin mixed 1:1 ratio. A drop of 50μl of the compound stain is added on 41.7mg of stool and stirred. This method illustrated the morphological appearance of S. mansoni and other soil transmitted intestinal parasites clearly when prepared and six weeks after preparation. The prepared slides maintained the morphological appearance including the eggs of hookworm after being kept in cool dry place for a long time. This method is reliable, reproducible, cost effective, easy to learn, quick and safe because of the base formalin, especially when handling specimens from Human Immunodeficiency virus infected patients.
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    Prevalence, infection intensity and associated risk factors of Intestinal Schistosomiasis among primary school Children in Lira District, Northern Uganda
    (Research Square, 2019) Byagamy, John Paul; Malinga, Geoffrey Maxwell; Angwech, Harriet; Opiro, Robert; Echodu, Richard; Odongo-Aginya, Emmanuel
    Abstract Objective: The aim of this cross-sectional study was to determine the prevalence, infection intensity and associated risk factors of intestinal schistosomiasis among primary school children in Lira district, Uganda. The study was conducted among 532 primary school pupils aged 6-16 years from eight randomly selected primary schools (March-May 2017). Stool samples were collected and examined for schistosomiasis using Odongo-Aginya method. Data on socio-demographic characteristics and risk factors were obtained using questionnaires. Results: The overall prevalence of Schistosoma mansoni was 35.7% indicating a moderate infection. Both males and females were equally affected with S. mansoni . Ogur sub county had highest prevalence (65.0%) than others. Akangi (65.5%) and Akano (64.5%) primary schools both had highest prevalence compared to the others. With regard to risk factors, source of drinking water, sub-county location and primary school were associated with prevalence of infection whereas only school location and home distance to water source was associated with intensity. Participants who fetch water from spring, dam and wells had higher infection than those who fetch from boreholes. The study recommends provision of safe water, periodic treatment of school-aged children with praziquantel and public health education to reduce prevalence of S. mansoni