Organ Pathology and Associated IFN-γ and IL-10 Variations in Mice Infected with Toxoplasma gondii Isolate from Kenya

Toxoplasma gondii is an important foodborne opportunistic pathogen that causes a severe disease in immunocompromised patients. The pathology and immune responses associated with the ensuing disease have not been well described in strains from different parts of the world. The aim of the present study is to determine the IFN-γ and IL-10 variations and organ pathology in immunocompetent and immunocompromised mice infected with T. gondii isolated from a Kenyan chicken. Two groups of BALB/c mice were infected with T. gondii cysts and administered with dexamethasone (DXM) in drinking water. Other two groups: infected untreated and uninfected mice were kept as controls. The mice were euthanized at various time points: blood collected for serum and assayed for IFN-γ and IL-10 variations. After infection, significant (p<0.05) elevated levels of IFN-γ and IL-10 were observed. A significant decline in IFN-γ and IL-10 levels (p<0.05) was observed after dexamethasone treatment. Histological sections in the liver, heart, and spleen of the mice administered with DXM revealed various degrees of inflammation characterized by infiltration of inflammatory cells. The dexamethasone-treated mice presented with progressively increased (p<0.001) inflammatory responses is compared with the infected untreated mice

IL-6 is Upregulated in Late-Stage Disease in Monkeys Experimentally Infected with Trypanosoma brucei rhodesiense

The management of human African trypanosomiasis (HAT) is constrained by lack of simple-to-use diagnostic, staging, and treatment tools. The search for novel biomarkers is, therefore, essential in the fight against HAT. The current study aimed at investigating the potential of IL-6 as an adjunct parameter for HAT stage determination in vervet monkey model. Four adult vervet monkeys (Chlorocebus aethiops) were experimentally infected with Trypanosoma brucei rhodesiense and treated subcuratively at 28 days after infection (dpi) to induce late stage disease. Three noninfected monkeys formed the control group. Cerebrospinal fluid (CSF) and blood samples were obtained at weekly intervals and assessed for various biological parameters. A typical HAT-like infection was observed. The late stage was characterized by significant (P<0.05) elevation of CSF IL-6, white blood cell count, and total protein starting 35 dpi with peak levels of these parameters coinciding with relapse parasitaemia. Brain immunohistochemical staining revealed an increase in brain glial fibrillary acidic protein expression indicative of reactive astrogliosis in infected animals which were euthanized in late-stage disease. The elevation of IL-6 in CSF which accompanied other HAT biomarkers indicates onset of parasite neuroinvasion and show potential for use as an adjunct late-stage disease biomarker in the Rhodesian sleeping sickness

Prevalence of Hepatitis C Virus Infection and Its Risk Factors among Patients Attending Rwanda Military Hospital, Rwanda

In Rwanda, the prevalence of viral hepatitis (HCV) is poorly understood. The current study investigated the prevalence and risk factors of HCV infection in Rwanda. A total of 324 patients attending Rwanda Military Hospital were randomly selected and a questionnaire was administered to determine the risk factors. Blood was collected and screened for anti-HCV antibodies and seropositive samples were subjected to polymerase chain reaction method. Hematology abnormalities in the HCV infected patients were also investigated. Anti-HCV antibody and active HCV infection were found in 16.0% and 9.6% of total participants, respectively. Prevalence was highest (28.4%; 19/67) among participants above 55 years and least (2.4%; 3/123) among younger participants (18-35 years). There was a significant ( = 0.031) relationship between place of residence and HCV infection with residents of Southern Province having significantly higher prevalence. The hematological abnormalities observed in the HCV infected patients included leukopenia (48.4%; 15/52), neutropenia (6.5%; 2/52), and thrombocytopenia (25.8%; 8/52). The HCV infection was significantly higher in the older population (&gt;55 years) and exposure to injection from traditional practitioners was identified as a significant ( = 0.036) risk factor of infection. Further studies to determine the factors causing the high prevalence of HCV in Rwanda are recommended

Characterisation of productivity and diseases affecting dairy goats in smallholder systems of Greater Thika Region, Kenya

The current cross-sectional study aimed at characterising the productivity and diseases affecting dairy goats kept by smallholder farmers in three sub-counties in Thika Region, Kenya. Standard questionnaires were administered to 240 farmers through face-to-face interviews and the outputs were analysed using descriptive and inferential statistics. The farmers mainly kept crosses of Toggenburg (45.9 %), Kenyan Alpine (29.5 %) and Saanen (17.4 %) dairy goats. The average dairy goat flock size was 4.5 (range 1–23) and 77.5 % of the goats were kept for production of milk for domestic consumption. The average milk production per goat per day was 1.26 litres (range 0.5 to 3.5 litres) and was significantly (p 0.05) associated with sub-county of origin, main occupation of the owner, breed, and lactation stages. Goats were mainly fed on napier grass, maize stovers, natural grass and hay; and these feeds did not influence (p 0.05) the milk production levels. The farmers identified helminthosis (84.6 %), pneumonia (32.9 %), coccidiosis (25.8 %) and mastitis (25 %), as the most prevalent goat diseases. In conclusion, the study showed that dairy goat farming in greater Thika Region was characterised by low-input with an objective of provision of milk for home consumption. The observed challenges of low milk productivity and diseases should be addressed by the local extension workers through training on improved husbandry, nutrition and health management of the dairy goats

Haematology of Experimental Trypanosoma Brucei Rhodesiense Infection in Vervet Monkeys

Haematological aberrations associated with human infective trypanosomes were investigated in the vervet monkey model of the Rhodesian sleeping sickness. Four monkeys were infected intravenously with 104 Trypanosoma brucei rhodesiense and monitored for changes in the blood profile using a haematological analyser. A chronic infection lasting between 48 and 112 days was observed. Microcytic hypochromic anaemia, which was characterized by a decline in packed cell volume (PCV), red blood cell (RBC) numbers, mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCH) developed at an early stage, and persisted throughout the infection. The mean platelet counts declined significantly from 3 x 105/\u3bcl (day 0 post infection) to 6.8 x 104/\u3bcl (day 7 post infection) and remained low in all the animals. However, the mean platelets volume rose during the course of the infection. An initial decline in total white blood cell (WBC) counts occurred between day 0 and 7 (3.1 x 106/\u3bcl) and remained low up to day 35 post infection (3.5 x 106/\u3bcl). This was followed by an increase in WBC counts, principally associated with increased lymphocyte numbers. It is concluded that microcytic hypochromic anaemia, thrombocytopaenia and an initial leucocytopaenia are the most important haematological changes associated with a chronic infection of T.b. rhodesiense infection in vervet monkeys

Pathogenicity of bloodstream and cerebrospinal fluid forms of Trypanosoma brucei rhodesiense in Swiss White Mice

Trypanosoma brucei rhodesiense (T.b.r.), the causative agent of the East African form of human African trypanosomiasis (HAT), is capable of crossing the blood brain barrier and invade the central nervous system (CNS). However, it is not clear whether bloodstream forms (BSF) of T.b.rhodesiense differ in biological characteristics from the cerebrospinal fluid (CSF) forms. The present study was carried out to compare the pathogenicity of CSF and BSF of T.b. rhodesiense parasites in Swiss white mice following intraperitoneal inoculation with 106 trypanosomes. The parasites were tested for presence of the serum resistance associated (SRA) gene. Parasitaemia, body weight, packed cell volume (PCV) and survival of the mice was monitored daily until the experiment was terminated. Data was analyzed using general linear model. Both forms of parasite were positive for the SRA gene, and there was no significant difference in progression of parasitaemia, PCV values or survival of the mice. However, the weights of BSF infected mice initially dropped faster than those of CSF infected mice (P&lt;0.001)

<i>Trypanosoma brucei rhodesiense</i> transmitted by a single tsetse fly bite in vervet monkeys as a model of human African trypanosomiasis

Sleeping sickness is caused by a species of trypanosome blood parasite that is transmitted by tsetse flies. To understand better how infection with this parasite leads to disease, we provide here the most detailed description yet of the course of infection and disease onset in vervet monkeys. One infected tsetse fly was allowed to feed on each host individual, and in all cases infections were successful. The characteristics of infection and disease were similar in all hosts, but the rate of progression varied considerably. Parasites were first detected in the blood 4-10 days after infection, showing that migration of parasites from the site of fly bite was very rapid. Anaemia was a key feature of disease, with a reduction in the numbers and average size of red blood cells and associated decline in numbers of platelets and white blood cells. One to six weeks after infection, parasites were observed in the cerebrospinal fluid (CSF), indicating that they had moved from the blood into the brain; this was associated with a white cell infiltration. This study shows that fly-transmitted infection in vervets accurately mimics human disease and provides a robust model to understand better how sleeping sickness develops

Toxicity and anthelmintic efficacy of chitosan encapsulated bromelain against gastrointestinal strongyles in Small East African goats in Kenya

Background and Aim: The development of resistance to anthelmintic drugs has prompted research into alternative methods of controlling intestinal nematodes in ruminants. This study aimed at evaluating the in vitro and in vivo anthelmintic efficacy and toxicity of chitosan encapsulated bromelain in Small East African goats in Kenya. Materials and Methods: Adult mortality assay was performed using live Haemonchus contortus worms treated with encapsulated bromelain solution ranging from 0.125 mg/ml to 2 mg/ml. Percentage mortality of worms was calculated after 24 h and the lethal concentration 50% (LC50) determined. For the in vivo study, 18 healthy male indigenous goats were divided into six groups of three goats each. The encapsulated bromelain was orally administered in increasing dosages (3-30 mg kg) once daily, for 14 days. The packed cell volume (PCV), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, and fecal egg count (FEC) were determined on a weekly basis. At the end of the study, the goats were sacrificed and gross pathology and histopathology of main organs assessed. Results: Albendazole had the highest (p0.05), varied from 29.3% to 35.1%, and was within the normal range of the animal. Likewise, no significant differences (p>0.05) were observed between the AST, ALT, urea, and creatinine levels of treated and the control (non-treated) goats. No adverse clinical symptoms, toxicity of the main organs, and mortality in goats were associated with the chitosan encapsulated bromelain after administration of dose up to 30 mg/kg for 14 days. Therefore, the lethal dose 50 of encapsulated bromelain may be considered to be >30 mg/kg. On day 28 post-treatment, the encapsulated bromelain showed a higher in vivo FEC reduction (68.8%) as compared to the plain bromelain (32.4%). Conclusion: Our results show that bromelain encapsulated in chitosan may be safe and effective in reducing the burden of gastrointestinal tract strongyle nematodes in goats. However, there is a need for further studies to establish the dosage of the encapsulated bromelain to be administered in a single dose for the treatment of goats against gastrointestinal strongyles. In addition, species-specific studies on the efficacy of encapsulated bromelain on strongyles are necessary to evaluate its effectiveness against the entire Strongyloididae family

Prevalence of Hepatitis C Virus Infection and Its Risk Factors among Patients Attending Rwanda Military Hospital, Rwanda

In Rwanda, the prevalence of viral hepatitis (HCV) is poorly understood. The current study investigated the prevalence and risk factors of HCV infection in Rwanda. A total of 324 patients attending Rwanda Military Hospital were randomly selected and a questionnaire was administered to determine the risk factors. Blood was collected and screened for anti-HCV antibodies and seropositive samples were subjected to polymerase chain reaction method. Hematology abnormalities in the HCV infected patients were also investigated. Anti-HCV antibody and active HCV infection were found in 16.0% and 9.6% of total participants, respectively. Prevalence was highest (28.4%; 19/67) among participants above 55 years and least (2.4%; 3/123) among younger participants (18–35 years). There was a significant (P=0.031) relationship between place of residence and HCV infection with residents of Southern Province having significantly higher prevalence. The hematological abnormalities observed in the HCV infected patients included leukopenia (48.4%; 15/52), neutropenia (6.5%; 2/52), and thrombocytopenia (25.8%; 8/52). The HCV infection was significantly higher in the older population (>55 years) and exposure to injection from traditional practitioners was identified as a significant (P=0.036) risk factor of infection. Further studies to determine the factors causing the high prevalence of HCV in Rwanda are recommended