Samuel Amwayi

An Investigation of a Major Outbreak of Rift Valley Fever in Kenya: 2006–2007

An outbreak of Rift Valley fever (RVF) occurred in Kenya during November 2006 through March 2007. We characterized the magnitude of the outbreak through disease surveillance and serosurveys, and investigated contributing factors to enhance strategies for forecasting to prevent or minimize the impact of future outbreaks. Of 700 suspected cases, 392 met probable or confirmed case definitions; demographic data were available for 340 (87%), including 90 (26.4%) deaths. Male cases were more likely to die than females, Case Fatality Rate Ratio 1.8 (95% Confidence Interval [CI] 1.3-3.8). Serosurveys suggested an attack rate up to 13% of residents in heavily affected areas. Genetic sequencing showed high homology among viruses from this and earlier RVF outbreaks. Case areas were more likely than non-case areas to have soil types that retain surface moisture. The outbreak had a devastatingly high case-fatality rate for hospitalized patients. However, there were up to 180,000 infected mildly ill or asymptomatic people within highly affected areas. Soil type data may add specificity to climate-based forecasting models for RVF.

High Mortality in a Cholera Outbreak in Western Kenya after Post-Election Violence in 2008

In 2008, a cholera outbreak with unusually high mortality occurred in western Kenya during civil unrest after disputed presidential elections. Through active case finding, we found a 200% increase in fatal cases and a 37% increase in surviving cases over passively reported cases; the case-fatality ratio increased from 5.5% to 11.4%. In conditional logistic regression of a matched case-control study of fatal versus non-fatal cholera infection, home antibiotic treatment (odds ratio [OR] 0.049; 95% CI: < 0.001-0.43), hospitalization (OR, 0.066; 95% CI, 0.001-0.54), treatment in government-operated health facilities (OR, 0.15; 95% CI, 0.015-0.73), and receiving education about cholera by health workers (OR, 0.19; 95% CI, 0.018-0.96) were protective against death. Among 13 hospitalized fatal cases, chart review showed inadequate intravenous and oral hydration and substantial staff and supply shortages at the time of admission. Cholera mortality was under-reported and very high, in part because of factors exacerbated by widespread post-election violence.

A national cholera epidemic with high case fatality rates--Kenya 2009.

BACKGROUND Cholera remains endemic in sub-Saharan Africa. We characterized the 2009 cholera outbreaks in Kenya and evaluated the response. METHODS We analyzed surveillance data and estimated case fatality rates (CFRs). Households in 2 districts, East Pokot (224 cases; CFR = 11.7%) and Turkana South (1493 cases; CFR = 1.0%), were surveyed. We randomly selected 15 villages and 8 households per village in each district. Healthcare workers at 27 health facilities (HFs) were surveyed in both districts. RESULTS In 2009, cholera outbreaks caused a reported 11 425 cases and 264 deaths in Kenya. Data were available from 44 districts for 6893 (60%) cases. District CFRs ranged from 0% to 14.3%. Surveyed household respondents (n = 240) were aware of cholera (97.5%) and oral rehydration solution (ORS) (87.9%). Cholera deaths were reported more frequently from East Pokot (n = 120) than Turkana South (n = 120) households (20.7% vs. 12.3%). The average travel time to a HF was 31 hours in East Pokot compared with 2 hours in Turkana South. Fewer respondents in East Pokot (9.8%) than in Turkana South (33.9%) stated that ORS was available in their village. ORS or intravenous fluid shortages occurred in 20 (76.9%) surveyed HFs. CONCLUSIONS High CFRs in Kenya are related to healthcare access disparities, including availability of rehydration supplies.

Aetiology and factors associated with bacterial diarrhoeal diseases amongst urban refugee children in Eastleigh, Kenya: A case control study

Introduction Kenya is home to over 400 000 refugees from neighbouring countries. There is scanty information about diarrhoea amongst urban refugees in Kenya. Objectives We investigated the enteric bacteria causing diarrhoea amongst urban refugee children and described the associated factors. Method During the period of August–December 2010, urban refugee children between the ages of two and five who attended Eastleigh County Council Health Centre were enrolled into the study. Diarrhoeal cases were compared with age-matched children with no diarrhoea (controls). Stool specimens were collected and enteric bacteria isolated. A questionnaire was administered to identify risk factors. Results A total of 41 cases and 41 controls were enrolled in the study. The age and country of origin were similar for cases and controls. The bacterial isolation rates amongst the cases were: non-pathogenic Escherichia coli 71%, Shigella dysenteriae 2.4%, Shigella flexneri 2.4%, Salmonella paratyphi 5%. For the controls, non-pathogenic E. coli 90% and enterotoxigenic E. coli (ETEC) 2.4% were amongst the organisms isolated. All isolates were resistant to amoxicillin; resistance to other antibiotics varied by isolate type. Factors associated independently with diarrhoea included children not washing their hands with soap (aOR 5.9, p < 0.05), neighbour(s) having diarrhoea (aOR 39.8, p < 0.05), children not exclusively breastfed for their first 6 months (aOR 7.6, p < 0.05) and children eating food cooked the previous day (aOR 23.8, p = 0.002). Conclusions Shigella species, Salmonella species and ETEC were found to be responsible for diarrhoea amongst the urban refugee children. Measures to control and guide the use of antibiotics are critical for the prevention of antibiotic resistance. Efforts to improve personal and domestic hygiene, including educational campaigns to promote appropriate handwashing, should be encouraged.

Knowledge and practices towards rabies and determinants of dog rabies vaccination in households: a cross sectional study in an area with high dog bite incidents in Kakamega County, Kenya, 2013.

Introduction An estimated 55,000 people die from rabies annually. Factors promoting dog vaccination, estimates of vaccination coverage and knowledge on rabies are important for effective rabies control. We sought to establish these estimates at household (HH) level and whether rabies knowledge is associated with proper control practices. Methods Cross-sectional cluster survey with two-stage sampling was employed in Kakamega County to enroll HH members above 18 years. A set of questions related to rabies knowledge and practice were used to score participant response. Score above the sample mean was equated to adequate knowledge and proper practices respectively. Independent t-test was used to evaluate the differences of sample mean scores based on dog vaccination status. Bivariate analysis was used to associate knowledge to practices. Results Three hundred and ninety HHs enrolled and had a population of 754 dogs with 35% (n = 119) HH having vaccinated dogs within past 12 months. Overall mean score for knowledge was 7.0 (±2.8) with range (0-11) and 6.3 (±1.2) for practice with range (0-8). There was a statistically significant difference in mean knowledge (DF = 288, p < 0.01) and practice (DF = 283, p = 0.001) of HH with vaccinated dogs compared to ones with unvaccinated dogs. Participants with adequate rabies knowledge were more likely to have proper health seeking practices 139 (80%) (OR = 3.0, 95% CI = 1.4-6.8) and proper handling practices of suspected rabid dog 327 (88%) (OR = 5.4, 95% CI = 2.7-10.6). Conclusion Rabies vaccination below the 80% recommended for herd immunity. Mass vaccination campaign needed. More innovative ways of translating knowledge into proper rabies control practice are warranted.

Prevalence of undiagnosed diabetes and pre-diabetes among hypertensive patients attending Kiambu district Hospital, Kenya: a cross-sectional study

Introduction Hypertension (HTN) and diabetes mellitus (DM) are two common non-communicable diseases (NCDs) that are closely linked: one cannot be properly managed without attention to the other. The aim of this study was to determine the prevalence of undiagnosed diabetic and pre-diabetic states that is abnormal glucose regulation (AGR) and factors associated with it among hypertensive patients in Kiambu Hospital, Kenya. Methods We conducted a cross-sectional study from February 2014 to April 2014. Hypertensive patients aged ≥18 attending the out-patient medical clinic were included in the study. Pregnant and known diabetic patients were excluded. Data was collected on socio-demographics, behavior, and anthropometrics. Diabetes status was based on a Glycated Haemoglobin (HbA1C) classification of ≥6.5% for diabetes, 6.0-6.4% for pre-diabetes and ≤6.0% for normal. AGR was the dependable variable and included two diabetic categories; diabetes and pre-diabetes. Results We enrolled 334 patients into the study: the mean age was 59 years (Standard deviation= 14.3). Of these patients 254 (76%) were women. Thirty two percent (107/334; 32%) were found to have AGR, with 14% (46) having un-diagnosed DM and 18%(61) with pre-diabetes. Factors associated with AGR were age ≥45 (OR = 3.23; 95% CI 1.37 ≥ 7.62), basal metabolic index (BMI) ≥ 25 Kg/m2 (OR= 3.13; 95% CI 1.53 - 6.41), low formal education (primary/none)(OR= 2; 95%CI 1.08 - 3.56) and family history of DM (OR = 2.19; 95%CI 1.16 - 4.15). Conclusion There was a high prevalence of undiagnosed AGR among hypertensive patients. This highlights the need to regularly screen for AGR among hypertensive patients as recommended by WHO.

Establishing a field epidemiology elective for medical students in Kenya: A strategy for increasing public health awareness and workforce capacity

Medical students have limited exposure to field epidemiology, even though will assume public health roles after graduation. We established a 10-week elective in field epidemiology during medical school. Students attended one-week didactic sessions on epidemiology, and nine weeks in field placement sites. We administered pre- and post-tests to evaluate the training. We enrolled 34 students in 2011 and 2012. In 2011, we enrolled five of 24 applicants from a class of 280 medical students. In 2012, we enrolled 18 of 81 applicants from a class of 360 students; plus 11 who participated in the didactic sessions only. Among the 34 students who completed the didactic sessions, 74% were male, and their median age was 24 years (range: 22–26). The median pre-test score was 64% (range: 47–88%) and the median post-test score was 82% (range: 72–100%). Successful completion of the field projects was 100%. Six (30%) students were not aware of public health as a career option before this elective, 56% rated the field experience as outstanding, and 100% reported it increased their understanding of epidemiology. Implementing an elective in field epidemiology within the medical training is a highly acceptable strategy to increase awareness for public health among medical students.

Assessing the prevalence of spina bifida and encephalocele in a Kenyan hospital from 2005–2010: implications for a neural tube defects surveillance system

Introduction Neural tube defects such as anencephaly, spina bifida, and encephalocele are congenital anomalies of the central nervous system. Data on the prevalence of neural tube defects in Kenya are limited. This study characterizes and estimates the prevalence of spina bifida and encephalocele reported in a referral hospital in Kenya from 2005-2010. Methods Cases were defined as a diagnosis of spina bifida or encephalocele. Prevalence was calculated as the number of cases by year and province of residence divided by the total number of live-births per province. Results From a total of 6,041 surgical records; 1,184 (93%) had reported diagnosis of spina bifida and 88 (7%) of encephalocele. Estimated prevalence of spina bifida and encephalocele from 2005-2010 was 3.3 [95% Confidence Interval (CI): 3.1-3.5] cases per 10,000 live-births. The highest prevalence of cases were reported in 2007 with 4.4 (95% CI: 3.9-5.0) cases per 10,000 live-births. Rift Valley province had the highest prevalence of spina bifida and encephalocele at 6.9 (95% CI: 6.3-7.5) cases per 10,000 live-births from 2005-2010. Conclusion Prevalence of spina bifida and encephalocele is likely underestimated, as only patients seeking care at the hospital were included. Variations in regional prevalence could be due to referral patterns and healthcare access. Implementation of a neural tube defects surveillance system would provide a more thorough assessment of the burden of neural tube defects in Kenya.

Tuberculosis infection among health care workers: a case series in two district hospitals, Kenya, August 2013

Introduction health care workers (HCWs) have an increased risk of M. tuberculosis infection and tuberculosis (TB) disease compared to the general population. We evaluated the magnitude of TB disease among HCWs in two District Hospitals in Kenya. Methods retrospective review of TB laboratory registers was performed at Makindu and Kiambu district hospitals. Cases were HCWs with confirmed TB diagnosis working at either hospital from 2010 to 2013. Cases were interviewed using structured questionnaire to collect clinical and epidemiologic information. Infection prevention (IP) practices were observed and recorded. Results Makindu and Kiambu had 91 and 450 HCWs respectively. As from the registers, 6,275 sputum smears were examined with 1,122 (18%) acid alcohol fast bacilli smear positive. Kiambu and Makindu reported 11 and five cases of TB among HCWs respectively. Of the 16, 57% were male; mean age was 45 (SD 5.32) years. HCWs affected were: four (25%) laboratory technicians, four (25%) nurses, two (13%) occupation therapists, two (13%) clinical officers and one pharmacist, telephone operator, driver and casual worker. Mean working time lost recuperating was 14 (range: 0-28) weeks. Both facilities lacked high-efficiency particulate air filters and Kiambu hospital lacked a biosafety cabinet too. Windows at both facilities were often closed and suspected TB patients shared common crowded outpatient waiting area where sputum was also collected. No standard reporting tool for TB disease among HCWs was in place at both facilities. Conclusion TB disease was distributed across professional cadres with long working time lost recuperating. Inadequate IP measures exposed HCWs to occupational risk of acquiring TB disease.

Strengthening health systems in Africa: a case study of the Kenya field epidemiology training program for local frontline health workers

The logistical and operational challenges to improve public health practice capacity across Africa are well documented. This report describes Kenya’s Field Epidemiology and Laboratory Training Program’s (KFELTP) experience in implementing frontline public health worker training to transfer knowledge and practical skills that help strengthen their abilities to detect, document, respond to, and report unusual health events.Between May 2014 and May 2015, KFELTP hosted five training courses across the country to address practice gaps among local public health workers. Participants completed a 10-week process: two 1-week didactic courses, a 7-week field project, and a final 1-week course to present and defend the findings of their field project. The first year was a pilot period to determine whether the program could fit into the existing 2-year KFELTP model and whether this frontline-level training would have an impact on local practice. At the end of the first year, KFELTP certified 167 frontline health workers in field epidemiology and data management. This paper concludes that local, national, and international partnerships are critical for improving local public health response capacity and workforce development training in an African setting.