Distribution and Transmission Dynamics of Plasmodium falciparum Malaria in Kenya

Plasmodium falciparum is the most popular and deadly malaria parasite in Kenya. Its transmission is dependent on numerous biotic and abiotic factors. Biotic factors include mosquito and malaria parasite density in the population and the proximity to mosquito breeding sites. Abiotic factors include socio-economic background of the population and malaria intervention strategies. These factors differ from one location to another and from one social setting to another. These variations ultimately influence malaria transmission in diverse locations and settings and limit the success in global approach to malaria control. This paper reviews the influence of both biotic and abiotic factors in relation to malaria transmission and the current status of these factors over time in Kenya. We hypothesize that changes in biotic and abiotic factors is responsible for the alteration in the mosquito and the Plasmodium falciparum density and distribution, hence malaria transmission in Kenya. An insight into these factors will guide in developing effective Malaria intervention strategies in the country. Keywords: Malaria, Plasmodium falciparum, Risk factor, Transmission

Prevalence of zoonotic Cryptosporidium spp. Isolates In Njoro Sub-County, Nakuru County, Kenya

Background: There is no information on human and animal Cryptosporidium spp. in Njoro sub- county. The risk posed to humans and animals within the sub-county is therefore unknown.Materials and Methods: A total of 1476 animal and 378 human fecal samples were evaluated. Multivariate logistic regression was used to evaluate association between infection status and the predisposing factors. Results were expressed as odds ratio (OR) with a 95%  confidence interval. Chi-square and Maentel–Haenszel tests were used to quantify relationships among variables.Results: Prevalence of Cryptosporidium spp. was 9.8% in humans, 10.8% in cows, 19.6% in sheep and 4.5% in goats. Prevalence in humans was significantly higher in females 12/37. Infection was highest in the elderly (27.27%), and significantly lower in adolescents and adults at 8.66% and 9.59%, respectively. Goats had lowest overall parasitization at all levels, while sheep had the highest parasitization at levels (+1 and +2). Relatively, humans had the highest parasite counts +3 cases (1.5%).Conclusion: Cryptosporidium spp. is prevalent in Njoro sub-county and domestic animals are important reservoirs and a potential source of zoonosis in humans. Children, elderly and females are at increased risk of infection, especially during rainy season. The study  recommends maintenance of proper sanitation when handling domestic animals, treatment of drinking water and use of alternative safer sources of water in order to reduce infection

Prevalence of porcine cysticercosis among scavenging pigs in western Kenya

Background: Porcine Cysticercosis (PC) infection is globally classified as a neglected and re-emerging tropical disease. The disease is endemic in Western Kenya yet smallholder farmers continue to practice scavenging pig production, thereby posing public health risk. This study determined the prevalence of PC infection at the farms and slaughter slabs in a cross-sectional survey in two Counties (Busia and Kakamega) of Western Kenya. Materials and Methods: Two hundred and eighty-seven (287) heparinized blood samples were collected at the farm from 162 households in 9 villages and 113 pigs from 5 slaughter slabs. The prevalence of PC was detected through meat inspection at slaughter slabs, and the prevalence of Taenia solium antigen determined by using the ApDia AgELISA test at the farms and slaughter slabs. Results: At meat inspection, the PC prevalence was 1.8%, while prevalence of Taenia Species cysts detected with AgELISA test was 3.8% at the farms, and 5.3 % at the slaughter slabs. The Ag-ELISA test had sensitivity of 100% (95% CI: 19.79– 100.00) and specificity of 96.4% (95% CI: 90.49– 98.84). Conclusion: The PC prevalence levels observed among scavenging pigs in Western Kenya should be a cause of public health risk concern. This observation warrant enforcing mandatory pig confinement, and use of latrines at the farms and meat inspection at local slaughter slabs. Further studies are recommended to identify different Taenia species in cysticercoids pigs in the region, which this study could not differentiate. Keywords: Pig, Taenia spps, meat inspection, ELISA test, Slaughter slabs, Smallholder farmers

Molecular Identification of African Trypanosome Stabilates from Livestock in Lamu County, Kenya

A study was conducted to characterize infectious trypanosomes in domestic animals within Lamu County, Kenya, using parasitological and molecular techniques. Fifteen trypanosome stabilates and 92 whole blood samples collected from parasitologically negative animals were randomly retrieved from the cryobank freezer at the Biotechnology Research Institute, (KALRO-BioRI), Kenya, and characterized. Human serum resistance associated (SRA) gene present in T. b. rhodesiense was used to differentiate T. brucei positive stabilates. Results showed that 10/15(67%) trypanosome stabilates and 13/92(14%) whole blood samples from cattle, donkeys and goats were positive using PCR. Positive T. congolense 5/23(22%) yielded a product size of 700bp using ITS1 primers. The Brucei group 7/23(30%) and T. vivax 11/23(48%) amplicons were 480bp and 250bp, respectively.  Identified trypanosome stabilates were T. b. brucei (7) T. vivax (2) and T. congolense Savannah (1). Whole blood PCR profiles revealed 13 isolates namely T. vivax (9) and T. congolense Savannah (4). Trypanosoma b. brucei, T. vivax and T. congolense Savannah were the etiological agents for AAT in donkeys. In contrast, T. vivax and T. congolense Savannah caused the disease in cattle, and T. b. brucei in goat within Lamu County. The study underscores the significance of molecular and parasitological methods during epidemiological monitoring and surveillance of disease. Keywords: Trypanosomes, livestock, PCR, Lamu County, Keny

Characterization of HC58cDNA, a putative cysteine protease from the parasite Haemonchus contortus

Because of the complexity of the cathepsin B-like (CBL) family, an information on the biological and biochemical characteristics of individual CBL genes is lacking. In this study, we investigated the degradative effects of the recombinant HC58 protein isolated from Haemonchus contortus parasites on protein substrates over a broad pH range in vitro. This protein, which hydrolyzed the synthetic peptide substrates Z-FR-AMC and Z-RR-AMC, had characteristics of the cysteine protease class of proteins. In the acidic pH range, the isolated protein actively degraded hemoglobin (Hb), the heavy chain of goat immunoglobulin G, and azocasein. By contrast, it degraded fibrinogen in the alkaline pH range. These activities were strongly inhibited in the presence of the cysteine protease inhibitor E-64. While the protein digested Hb, it did not induce the agglutination of erythrocytes from its natural host. These results suggest that the HC58 protein may play a role in the nutrition of this parasite

EPIDEMIOLOGY OF ZOONOTIC Cryptosporidium spp. ISOLATES IN NJORO SUB_COUNTY NAKURU COUNTY, KENYA

ABSTRACT Cryptosporidium spp. are coccidian, oocysts-forming apicomplexan protozoans, which complete their life cycle both in humans and animals. In this study, Cryptosporidium spp. circulating in human and domestic animals along Njoro sub county was evaluated using microscopy with an aim of determining the level of Cryptosporidium spp. infections in domestic animals and humans. A total of 1476 animal and 378 human fecal samples were collected from homesteads and public health facilities, respectively within the Sub County These samples were processed, purified and oocysts isolated from microscopically positive stool samples. Data was subjected to an Analysis of Variance (ANOVA), t-test and Chi-square tests using R-Studio software to compare the differences in prevalence of Cryptosporidium spp. oocysts between feacal samples of human and animals with regard to parasitemia, season, age, sex and source of water at a 5% level of significance.Results of the study showed Cryptosporidium spp. was more prevalent in domestic animals than in humans. Prevalence of Cryptosporidium spp. in humans is significantly higher in females than in males. Cryptosporidium spp. infection is higher in the older individuals and children and lowest in adolescents and adults. The prevalence of Cryptosporidium spp. was relatively higher in wet and rainy months peaking in July than in dry seasons where prevalence was lowest in December, January and February. The study has concluded that cryptosporidium spp. is prevalent in Njoro Sub County and has highlighted domestic animals as an important reservoir for Cryptosporidium spp. and potential source of zoonosis of this infection in humans

PORCINE CYSTICERCOSIS RISKS: AWARENESS, ATTITUDES AND PERCEPTIONS ON SAFETY PRACTICES AMONG FARMERS, BUTCHER-OWNERS AND CONSUMERS IN WESTERN KENYA

Background: The demand for pork is increasing in Africa with the increasing need for animal protein in the household diets. But pork safety and quality remains a pervasive concern that needs intervention to assure consumers of protection from Porcine Cysticercosis (PC) contamination. This study assessed among farmers, butcher-owners and consumers in Western Kenya about their awareness, attitudes and perceptions about safety practices regarding risk of PC. Materials and Methods: Data were obtained using structured questionnaires in cross-sectional survey interviews with 162 farmers, 26 butcher-owners and 92 consumers from Busia and Kakamega Counties. The data were in binary response, so were analyzed with Chi-square test. Results: Only two in ten farmers had knowledge of Taenia solium parasite (24.1%), risk factors in PC transmission (21.6%) and could associate pig management system with PC (17.3%). A larger proportion (p<0.01) of the butcher owners perceived pork from slaughter slabs (76.9%) and home slaughters (73.1%) as presenting high risks but considered pork from the butcheries (69.1%) and eateries (61.5%) as presenting no risks. Among the consumers, majority strongly agreed (p<0.05) that pork in the market (85.9%), from slaughter slabs (92.4%) and butchery (81.5%) was safe but a larger proportion strongly disagreed that pork from the eateries exposed them to cysticercosis (64.1%). Conclusion: The awareness about risks of PC was low among farmers. Butcher-owners and consumers perceived pork safety differently along the value chain. Strengthening public education about PC risks and pork safety among all actors in the pork value chain in Western Kenya is recommended

PREVALENCE OF PORCINE CYSTICERCOSIS AMONG SCAVENGING PIGS IN WESTERN KENYA

Background: Porcine Cysticercosis (PC) infection is globally classified as a neglected and re-emerging tropical disease. The disease is endemic in Western Kenya yet smallholder farmers continue to practice scavenging pig production, thereby posing public health risk. This study determined the prevalence of PC infection at the farms and slaughter slabs in a cross-sectional survey in two Counties (Busia and Kakamega) of Western Kenya. Materials and Methods: Two hundred and eighty-seven (287) heparinized blood samples were collected at the farm from 162 households in 9 villages and 113 pigs from 5 slaughter slabs. The prevalence of PC was detected through meat inspection at slaughter slabs, and the prevalence of Taenia solium antigen determined by using the ApDia Ag-ELISA test at the farms and slaughter slabs. Results: At meat inspection, the PC prevalence was 1.8%, while prevalence of Taenia Species cysts detected with Ag-ELISA test was 3.8% at the farms, and 5.3 % at the slaughter slabs. The Ag-ELISA test had sensitivity of 100% (95% CI: 19.79– 100.00) and specificity of 96.4% (95% CI: 90.49– 98.84). Conclusion: The PC prevalence levels observed among scavenging pigs in Western Kenya should be a cause of public health risk concern. This observation warrant enforcing mandatory pig confinement, and use of latrines at the farms and meat inspection at local slaughter slabs.  Further studies are recommended to identify different Taenia species in cysticercoids pigs in the region, which this study could not differentiat

Porcine Cysticercosis Control in Western Kenya: The Interlink of Management Practices in Pig Farms and Meat Inspection Practice at Slaughter Slabs

This study assessed the management practices for controlling porcine cysticercosis (PC) on pig farms and in pork at the slaughter slabs in two counties (Busia and Kakamega) of Western Kenya. A total of 162 pig-rearing households at the farm level, 26 butcher owners, and 26 slaughter slab workers at the slaughter slab level were interviewed using a structured questionnaire. Data were analyzed using the “Statistical Analysis System” (SAS) programme. Results indicated that the frequent management practices used at the farm level (p<0.05) were rearing pigs under free range (69.1%), latrine ownership by households (87.7%), and use of pit latrines (72.8%) in households. At the slaughter level (p<0.05), results of the butcher owners (76.9%) and slaughter slab workers (62.5%) revealed that meat inspection was not practiced adequately in the two areas of study. The results imply that slaughtered pigs for human consumption were not adequately inspected, and thus, the study recommends for implementation of effective pig management practices at the farm level and pork meat inspection at slaughter slabs to prevent PC infections and assure food safety along the pork value chain