School of Health Sciences
http://ir.jooust.ac.ke/handle/123456789/110
2024-03-28T14:05:51ZFinancial Accounting
http://ir.jooust.ac.ke/handle/123456789/11065
Financial Accounting
MBA 803
2019-01-01T00:00:00ZLarval species diversity, seasonal occurrence and larval habitat preference of mosquitoes transmitting Rift Valley fever and malaria in Baringo County, Kenya
http://ir.jooust.ac.ke/handle/123456789/7982
Larval species diversity, seasonal occurrence and larval habitat preference of mosquitoes transmitting Rift Valley fever and malaria in Baringo County, Kenya
Ondiba, Isabella M.; Oyieke, Florence A.; Athinya, Duncan K.; Estambale, Benson B. A.
Background: Baseline information that is essential for determining the areas to target with larval control includes estimates of vector diversity and larval habitat preferences. Due to a lack of such information in Baringo County, Kenya, this study assessed species diversity and larval habitat preference of potential mosquito vectors of Rift Valley fever (RVF) and malaria.
Methods: Mosquito larvae were sampled from nine types of larval habitats and were identified morphologically. Species diversity was estimated by the Shannon’s diversity index while larval habitat preference by RVF and malaria vectors was determined by ANOVA.
Results: A total of 7724 immature mosquitoes comprising 17 species belonging to four genera, namely Anopheles, Culex, Aedes and Mansonia, were identified. Among the 17 species, three Anopheles species are responsible for malaria transmission: An. gambiae (s.l.), An. funestus (s.l.) and An. pharoensis. Rift Valley fever vectors included Mansonia spp. and Culex spp. The highest Shannon’s diversity index was observed during the cold dry season (H = 2.487) and in
the highland zone (H = 2.539) while the lowest diversity was recorded during the long rain season (H = 2.354) and in the riverine zone (H = 2.085). Ditches had the highest mean number of Anopheles larvae (16.6 larvae per sample) followed by swamp (12.4) and seasonal riverbed (10.7). Water pit and water pan had low mean numbers of Anopheles larvae (1.4 and 1.8, respectively) but relatively high mean numbers of culicines (16.9 and 13.7, respectively). Concrete tank was the least sampled type of habitat but had highest mean number of culicine larvae (333.7 l) followed distantly by water spring (38.9) and swamp (23.5). Overall, larval habitats were significantly different in terms of larval density (F(8,334) = 2.090, P = 0.036).
Conclusions: To our knowledge, the present study reports culicine larval species diversity in Baringo for the first time and the most preferred habitats were concrete tanks, water springs and swamps. Habitats preferred by Anopheles were mainly riverbed pools, ditches and swamps. Environmental management targeting the habitats most preferred by potential vectors can be part of integrated vector control in Baringo, especially during dry seasons.
Open Access
2019-06-11T00:00:00ZLarval species diversity, seasonal occurrence and larval habitat preference of mosquitoes transmitting Rift Valley fever and malaria in Baringo County, Kenya
http://ir.jooust.ac.ke/handle/123456789/7980
Larval species diversity, seasonal occurrence and larval habitat preference of mosquitoes transmitting Rift Valley fever and malaria in Baringo County, Kenya
Ondiba, Isabella M.; Oyieke, Florence A.; Athinya, Duncan K.; Nyamongo, Isaac K.; Estambale, Benson B. A.
Background: Baseline information that is essential for determining the areas to target with larval control includes estimates of vector diversity and larval habitat preferences. Due to a lack of such information in Baringo County, Kenya, this study assessed species diversity and larval habitat preference of potential mosquito vectors of Rift Valley fever (RVF) and malaria.
Methods: Mosquito larvae were sampled from nine types of larval habitats and were identified morphologically. Species diversity was estimated by the Shannon’s diversity index while larval habitat preference by RVF and malaria vectors was determined by ANOVA.
Results: A total of 7724 immature mosquitoes comprising 17 species belonging to four genera, namely Anopheles, Culex, Aedes and Mansonia, were identified. Among the 17 species, three Anopheles species are responsible for malaria transmission: An. gambiae (s.l.), An. funestus (s.l.) and An. pharoensis. Rift Valley fever vectors included Mansonia spp. and Culex spp. The highest Shannon’s diversity index was observed during the cold dry season (H= 2.487) and in the highland zone (H= 2.539) while the lowest diversity was recorded during the long rain season (H= 2.354) and in the riverine zone (H= 2.085). Ditches had the highest mean number of Anopheles larvae (16.6 larvae per sample) followed by swamp (12.4) and seasonal riverbed (10.7). Water pit and water pan had low mean numbers of Anopheleslarvae (1.4 and 1.8, respectively) but relatively high mean numbers of culicines (16.9 and 13.7, respectively). Concrete tank was the least sampled type of habitat but had highest mean number of culicine larvae (333.7 l) followed distantly by water spring (38.9) and swamp (23.5). Overall, larval habitats were significantly different in terms of larval density (F(8,334)= 2.090, P= 0.036).
Conclusions: To our knowledge, the present study reports culicine larval species diversity in Baringo for the first time and the most preferred habitats were concrete tanks, water springs and swamps. Habitats preferred by Anopheleswere mainly riverbed pools, ditches and swamps. Environmental management targeting the habitats most preferred by potential vectors can be part of integrated vector control in Baringo, especially during dry seasons.
https://doi.org/10.1186/s13071-019-3557-x
2019-01-01T00:00:00ZAnimal-related factors associated with moderate-to-severe diarrhea in children younger than five years in western Kenya: A matched case-control study
http://ir.jooust.ac.ke/handle/123456789/2962
Animal-related factors associated with moderate-to-severe diarrhea in children younger than five years in western Kenya: A matched case-control study
Conan, Anne; O’Reilly, Ciara E.; Ogola, Eric; Ochieng, Benjamin J.; Blackstock, Anna J.; Omore, Richard; Ochieng, Linus; Moke, Fenny; Parsons, Michele B.; Xiao, Lihua; Roellig, Dawn; Farag, Tamer H.; Nataro, James P.; Knobel, Darryn L.
Background
Diarrheal disease remains among the leading causes of global mortality in children younger than 5 years. Exposure to domestic animals may be a risk factor for diarrheal disease. The objectives of this study were to identify animal-related exposures associated with cases of moderate-to-severe diarrhea (MSD) in children in rural western Kenya, and to identify the major zoonotic enteric pathogens present in domestic animals residing in the homesteads of case and control children.
Methodology/Principal findings
We characterized animal-related exposures in a subset of case and control children (n = 73 pairs matched on age, sex and location) with reported animal presence at home enrolled in the Global Enteric Multicenter Study in western Kenya, and analysed these for an association with MSD. We identified potentially zoonotic enteric pathogens in pooled fecal specimens collected from domestic animals resident at children’s homesteads. Variables that were associated with decreased risk of MSD were washing hands after animal contact (matched odds ratio [MOR] = 0.2; 95% CI 0.08–0.7), and presence of adult sheep that were not confined in a pen overnight (MOR = 0.1; 0.02–0.5). Variables that were associated with increased risk of MSD were increasing number of sheep owned (MOR = 1.2; 1.0–1.5), frequent observation of fresh rodent excreta (feces/urine) outside the house (MOR = 7.5; 1.5–37.2), and participation of the child in providing water to chickens (MOR = 3.8; 1.2–12.2). Of 691 pooled specimens collected from 2,174 domestic animals, 159 pools (23%) tested positive for one or more potentially zoonotic enteric pathogens (Campylobacter jejuni, C. coli, non-typhoidal Salmonella, diarrheagenic E. coli, Giardia, Cryptosporidium, or rotavirus). We did not find any association between the presence of particular pathogens in household animals, and MSD in children.
Conclusions and significance
Public health agencies should continue to promote frequent hand washing, including after animal contact, to reduce the risk of MSD. Future studies should address specific causal relations of MSD with sheep and chicken husbandry practices, and with the presence of rodents.
2017-08-04T00:00:00ZFactors associated with default from TB treatment among tuberculosis patients in Busia County
http://ir.jooust.ac.ke/handle/123456789/2868
Factors associated with default from TB treatment among tuberculosis patients in Busia County
Mwangi, Brian Kedode; Ayodo, George; Khagayi, Sammy; Tengo, Laura; Makori, Moseti; Munyasia, Linnet
Tuberculosis remains a major health problem in many tropical countries, including Kenya. Defaulting from treatment has been an obstacle to treatment management control. Inability to complete the prescribed regimen is quite common in self-administered treatment and an important cause for treatment failure, relapses, acquired drug resistance and on-going transmission of infection. The objective was to determine factors associated with default from TB treatment in Busia County. A Cross-sectional descriptive study was conducted on 249 patients; sequential enrolment was conducted of TB patients collecting drugs within Busia County. The data was then converted to Stata 13 for further analysis. Descriptive statistics was used in the form of frequencies, tables, charts and graphs. To assess the association, Chi-square tests (����), t-test (for numerical variables) was used. Association was further tested using regression models; I carried out a univariate analysis on all the indicator variables and checked for statistical significance at 95% confidence intervals. Out of 249 study participants, 17 % (42) were defaulters and 83 % (207) were non-defaulters and males were 61% (152) while females were 39% (98). The characteristics that were statistically significant were history of alcohol consumption (OR 3.20; 95% CI 1.50 to 6.84 and P value 0.003), history and quantity of cigarette smoking (OR 3.20; 95% CI 1.50 to 6.84 and P value 0.001), vomiting (OR 2.07; 95% CI 1.06 to 4.06 and P value 0.033) and nausea (OR 1.99; 95% CI 1.01 to 3.89 and P value 0.046) as side effects experienced during taking TB drugs and taking TB drugs before meals (OR 1.99; 95% CI 1.01 to 3.89 and P value 0.043). Adherence to TB treatment in Busia County is a behavioral issue involving patient factors; alcohol intake, health care poor attitude and cigarette smoking that were most cited reasons for default, side effects were also cited to be a reason for defaulting like vomiting and nausea. Measures on patient behavioral indicators and maintenance of an effective communication channel between health facilities and patients during the treatment more focus on healthcare motivation, training and track patients on their intensive phase of treatment is recommended
2016-08-01T00:00:00ZKnowledge, practices and perception of health care workers on diagnosis of childhood tuberculosis: a case study of Bureti Sub County, Kericho, Kenya
http://ir.jooust.ac.ke/handle/123456789/2863
Knowledge, practices and perception of health care workers on diagnosis of childhood tuberculosis: a case study of Bureti Sub County, Kericho, Kenya
Kipkosgei, Kirui Collins; Omesa, Eunice; Joseph, Choge; Ayodo, George
Background: Despite the advances in the diagnosis of tuberculosis, effective diagnosis remains a challenge among children. Several countries have rolled out effective diagnostic methods but capacity of health care workers to achieve expected resultshave not been evaluated. The objective of this study was therefore to assess the knowledge, practices and perception of health care workers on diagnosis of childhood tuberculosis at public and private health facilities in Bureti sub-county, Kenya. This is important for effective diagnosis hence reduced childhood deaths.
Methods:A cross-sectional study was carried out on44 health care workers in 10TB clinic in both public and private health facilities. The data collection tools were key informant guide and semi-structured questionnaire.
Results:Majority of Health care workers(45.5%)have poor knowledge,with 31.8%mentioning that mycobacterium leprae also causes TB. On practices, 68% confirms that gene expert is available in the health facilities but only 30% can interpret its results and 20% do not know how to use it. Majority of the respondents (61.4 %) believe stigma still remain a challenge in diagnosis of TB.
Conclusion:Knowledge, practices and perception need to be improved among the health care providers for better diagnosis of childhood tuberculosis. There is a need for regular training on diagnostic methods and more importantly interpretation of results. In addition, there is a need for health education so address the challenges of community stigma. Also, the study recommends more studies in other counties to inform a national strategy for effective diagnosis of childhood TB.
2018-01-01T00:00:00ZInterferon-γ responses to Plasmodium falciparum vaccine candidate antigens decrease in the absence of malaria transmission
http://ir.jooust.ac.ke/handle/123456789/2859
Interferon-γ responses to Plasmodium falciparum vaccine candidate antigens decrease in the absence of malaria transmission
Ayieko, Cyrus; Ogola, Bilha S.; Ochola, Lyticia; Ngwena, Gideon A.M.; Ayodo, George; Hodges, James S.; Noland, Gregory S.; John, Chandy C.
Background
Malaria elimination campaigns are planned or active in many countries. The effects of malaria elimination on immune responses such as antigen-specific IFN- γ responses are not well characterized.
Methods
IFN- γ responses to the P. falciparum antigens circumsporozoite protein, liver stage antigen-1, thrombospondin-related adhesive protein, apical membrane antigen-1, MB2, and merozoite surface protein-1 were tested by ELISA in 243 individuals in highland Kenya in April 2008, October 2008, and April 2009, after a one-year period of interrupted malaria transmission from April 2007 to March 2008.
Results
While one individual (0.4%) tested positive for P. falciparum by PCR inOctober 2008 and another two (0.9%) tested positive in April 2009, no clinical malaria cases were detected during weekly visits. Levels of IFN-γ to all antigens decreased significantly from April 2008 to April 2009 (all P < 0.001).
Discussion
Naturally acquired IFN- γ responses to P. falciparum antigensare short-lived in the absence of repeated P. falciparum infection. Even short periods of malaria interruption may significantly decrease IFN-γ responses to P. falciparum antigens.
2017-01-10T00:00:00ZSensitivity of fever for diagnosis of clinical malaria in a Kenyan area of unstable, low malaria transmission
http://ir.jooust.ac.ke/handle/123456789/2848
Sensitivity of fever for diagnosis of clinical malaria in a Kenyan area of unstable, low malaria transmission
Mutanda, Albino L; Cheruiyot, Priscah; Hodges, James S; Ayodo, George; Odero, Wilson; John, Chandy C.
Background
Malaria in highland areas of Kenya affects children and adults. Local clinicians include symptoms other than fever when screening for malaria because they believe that fever alone does not capture all cases of malaria.
Methods
Individuals who presented to dispensaries in a highland Kenya site of low, unstable malaria transmission from 2007–2011 with 1 or more of 11 symptoms were tested by microscopy for malaria. Clinical malaria was defined as asexual Plasmodium falciparum infection on peripheral blood smear in an individual with any screening symptom. Asymptomatic P. falciparum infection was assessed in a cohort at ten time points to determine the extent to which symptomatic episodes with parasitaemia might be attributable to baseline (asymptomatic) parasitaemia in the community.
Results
3,420 individuals were screened for malaria, 634 < 5 years of age and 2,786 ≥ 5 years of age. For the diagnosis of clinical malaria, the symptom of fever had a sensitivity and specificity of 88.9% and15.4% in children <5 years, and 55.8% and 54.4% in children ≥5 years, respectively. Adding the symptom of headache increased sensitivity to 94. 4% in children <5 years and 96.8% in individuals ≥5 years, but decreased specificity to 9.9% and 11.6%, respectively, and increased the number of individuals who would be tested by 6% and 92%, respectively. No combination of symptoms improved upon the presence fever or headache for detection of clinical malaria. In the cohort of asymptomatic individuals, P. falciparum parasitaemia was infrequent (0.1%).
Conclusion
In areas of low, unstable malaria transmission, fever is a sensitive indicator of clinical malaria in children <5 years, but not in older children and adults. Adding headache to fever as screening symptom increases sensitivity of detection in individuals ≥5 years old at the cost of decreased specificity. Screening for symptoms in addition to fever may be required to accurately capture all cases of clinical malaria in individuals ≥5 years old in areas of low malaria transmission.
2014-04-30T00:00:00ZFactors associated with non-adherence to Artemisinin-based combination therapy (ACT) to malaria in a rural population from holoendemic region of western Kenya
http://ir.jooust.ac.ke/handle/123456789/2835
Factors associated with non-adherence to Artemisinin-based combination therapy (ACT) to malaria in a rural population from holoendemic region of western Kenya
Onyango, Elizabeth O.; Ayodo, George; Watsierah, Carren A; Were, Tom; Okumu, Wilson; Samuel, Anyona B.; Raballah, Evans; Okoth, John M.; Gumo, Sussy; Orinda, George O.; Ouma, Collins
Background
Over the years, reports implicate improper anti-malarial use as a major contributor of morbidity and mortality amongst millions of residents in malaria endemic areas, Kenya included. However, there are limited reports on improper use of Artemisinin-based Combination Therapy (ACT) which is a first-line drug in the treatment of malaria in Kenya. Knowing this is important for ensured sustainable cure rates and also protection against the emergence of resistant malarial parasites. We therefore investigated ACT adherence level, factors associated with non-adherence and accessibility in households (n = 297) in rural location of Southeast Alego location in Siaya County in western Kenya.
Methods
ACT Adherence level was assessed with reference to the duration of treatment and number of tablets taken. Using systematic random sampling technique, a questionnaire was administered to a particular household member who had the most recent malaria episode (<2 weeks) and used ACT for cure. Parents/caretakers provided information for children aged <13 years. Key Informant Interviews (KIIs) were also conducted with healthcare providers and private dispensing chemist operators.
Results
Adherence to ACT prescription remained low at 42.1% and 57.9% among individuals above 13 and less than 13 years, respectively. Stratification by demographic and socio-economic characteristics in relation to ACT adherence revealed that age (P = 0.011), education level (P < 0.01), ability to read (P < 0.01) and household (HH) monthly income (P = 0.002) significantly affected the level of ACT adherence. Consistently, logistic regression model demonstrated that low age (OR, 0.571, 95% CI, 0.360-0.905; P = 0.017), higher education level (OR, 0.074; 95% CI 0.017-0.322; P < 0.01), ability to read (OR, 0.285, 95% CI, 0.167-0.486; P < 0.01) and higher income (Ksh. > 9000; OR, 0.340; 95% CI, 0.167-0.694; P = 0.003) were associated with ACT adherence. In addition, about 52.9% of the respondents reported that ACT was not always available at the source and that drug availability (P = 0.020) and distance to drug source (P < 0.01) significantly affected accessibility.
Conclusions
This study demonstrates that more than half of those who get ACT prescription do not take recommended dose and that accessibility is of concern. The findings of this study suggest a potential need to improve accessibility and also initiate programmatic interventions to encourage patient-centred care.
2012-06-24T00:00:00ZGlobal diversity, population stratification, and selection of human copy-number variation
http://ir.jooust.ac.ke/handle/123456789/2831
Global diversity, population stratification, and selection of human copy-number variation
Sudmant, Peter H.; Ayodo, George
In order to explore the diversity and selective signatures of duplication and deletion human copy-number variants (CNVs), we sequenced 236 individuals from 125 distinct human populations. We observed that duplications exhibit fundamentally different population genetic and selective signatures than deletions and are more likely to be stratified between human populations. Through reconstruction of the ancestral human genome, we identify megabases of DNA lost in different human lineages and pinpoint large duplications that introgressed from the extinct Denisova lineage now found at high frequency exclusively in Oceanic populations. We find that the proportion of CNV base pairs to single-nucleotide–variant base pairs is greater among non-Africans than it is among African populations, but we conclude that this difference is likely due to unique aspects of non-African population history as opposed to differences in CNV load.
Abstruct
2015-09-11T00:00:00Z