Seroprevalence of Coxiella burnetii in patients presenting with acute febrile illness at Marigat District Hospital, Baringo County, Kenya.

Q fever is not routinely diagnosed in Kenyan hospitals. This study reports on Q fever in patients presenting at Marigat District Hospital, Kenya, with febrile illness. ELISA was used to detect Coxiella burnetii phase antigens. Of 406 patients, 45 (11.1%) were judged to have acute disease (phase II IgM or IgG > phase I IgG), 2 (0.5%) were chronic (phase I IgG titer >800 or phase I IgG > phase II IgG), while 26 (6.4%) had previous exposure (phase I IgG titer <800). Age (6-10 years, p = 0.002) and contact with goats (p = 0.014) were significant risk factors. Compared to immunofluorescence antibody test, the sensitivity and specificity for phase I IgG were 84% and 98%, respectfully, 46% and 100% for phase II IgG and 35% and 89% for phase II IgM. It is concluded that the low sensitivity of phase II ELISA underestimated the true burden of acute Q fever in the study population.

Evaluation of the antimicrobial activity and safety of Rhus vulgaris (Anacardiaceae) extracts.

BACKGROUND: Medicinal plants have been used in the treatment of various ailments in most developing countries. Oral infections are the most prevalent diseases in man. The Rhus family has been found to have antimicrobial, antimalarial, and anti-inflammatory properties. Few studies have been done on Rhus vulgaris Meikle. A study was conducted to determine the effect of Rhus vulgaris Meikle stem bark extracts against selected oral pathogenic microorganisms and the safety of the extracts in vitro and in vivo. METHODS: Methanol:dichloromethane (1:1), methanol and aqueous extracts were tested for bacteriostatic and bactericidal effects against Methicillin Resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Streptococcus mutans and Candida albicans. Cytotoxicity of the active extracts was determined using Vero E6 cell lines while safety was evaluated in mice and rats. Phytochemical screening was performed on the methanol extracts. One-way ANOVA and Tukey's multiple comparisons tests were performed using IBM SPSS statistics 20.0 for antimicrobial assay and acute toxicity testing. One-way ANOVA and Dunnett's multiple comparison tests were conducted using GraphPad Prism 8.0 for cytotoxicity assay. RESULTS: Methanol extract of Rhus vulgaris showed significant antimicrobial activity against MRSA (12.00 ± 0.00 mm; p-value of < 0.005; Minimum Inhibitory Concentration of 0.391 mg/ml; Minimum Bactericidal Concentration of 1.563 mg/ml). The extract were not cytotoxic at 100 µg/ml which was the highest tested concentration. In acute dermal irritation testing, the methanol extract resulted in mild irritation with erythema and flaking that cleared within 8 days. There were no observable adverse effects from oral administration of the extracts (acute oral toxicity testing) at concentrations of 50 mg/kg, 300 mg/kg and 2000 mg/kg. Tannins, saponins, flavonoids, terpenoids, glycosides, alkaloids and phenols were detected in the methanol extract. CONCLUSIONS: Antimicrobial activity of R. vulgaris extracts supports its traditional use as a toothbrush. Cytotoxicity demonstrated by the extracts as well as the mild skin irritation warrants further study before R. vulgaris can be recommended for the development of effective and safe mouthwashes.

Risk of Fungi Associated with Aflatoxin and Fumonisin in Medicinal Herbal Products in the Kenyan Market.

Utilization of herbal products is a major concern due to the possibility of contamination by toxigenic fungi that are mycotoxin producers such as Aspergillus species during processing and packaging. Research was carried out to determine the presence of aflatoxins and fumonisins in herbal medicinal products sold in Eldoret and Mombasa towns in Kenya. The study employed both exploratory and laboratory experimental design. The herbal products were purchased from the market and transported to Kenya Medical Research Institute for processing and analysis. Fungal contaminants were determined according to Pharmacopoeia specifications. The toxins were quantified using ELISA based technique. The genus Aspergillus was the most dominant followed by Penicillium. Fungal counts ranged between 1 CFU/g and >1000 cfu/g. Analysis of variance showed that the rate of fungal contaminants for Eldoret and Mombasa samples had significant association (p ≤ 0.001). Aflatoxin levels ranged from 1 to 24 ppb, while fumonisin levels ranged from 1 to >20 ppb. Only 31% of samples met the standards for microbial limits as specified in Pharmacopoeia. There is need for product microbial quality improvement through proper harvesting, processing, storage, and marketing. It is recommended that a policy be enacted to enable regulation of herbal products in Kenya.

Isolation and Assessment of Stability of Six Formulations of Entomopathogenic Beauveria bassiana.

Beauveria bassiana is the most widely studied and exploited entomopathogen. The development of a suitable formulation for B. bassiana is a critical component in aiding the entomopathogen germinate and infect the host. In addition to being economical to produce, having high residual activity, it is also important that the formulation is easy to handle, stable during storage, and convenient to mix and apply and be consistently effective in controlling the target pest.In this chapter we describe preparation of experimental formulations of conidia of B. bassiana. The formulations are prepared with barley, rice, wheat bran, clay, kaolin, and peat. The protocol for assessing the stability of the formulations of B. bassiana is also described.

Effect of surfactants and temperature on germination and vegetative growth of Beauveria bassiana.

Three non-ionic surfactants: Tween20, Tween80 and Breakthru (®) were screened for their effects on spore germination and mycelial growth rates and for their influence on three isolates of Beauveria bassiana spore germination at various temperatures. Tween20 and Tween80 were compatible with all the B. bassiana isolates in the germination studies, but inhibited germination at higher surfactant concentrations, irrespective of the conidial concentrations . Breakthru (®) had an inhibitory effect on germination even at the lowest concentration of 0.1% on all the B. bassiana isolates. The effects of the surfactants on spore germination did not correspond with their effects on colony growth. Conidial viability within the same formulation declined significantly with increases in temperature, irrespective of the surfactant. The optimal temperature for conidial germination of B. bassiana isolates was approximately 25 °C with an upper limit at 30 °C. Isolate 7320 was identified as the least affected by the different surfactants. This isolate was able to germinate rapidly in a broad temperature range of 25-30 °C after 24 h, this characteristic being an essential factor in controlling house fly populations in poultry houses.

Effect of surfactants and temperature on germination and vegetative growth of Beauveria bassiana

Three non-ionic surfactants: Tween20, Tween80 and Breakthru® were screened for their effects on spore germination and mycelial growth rates and for their influence on three isolates of Beauveria bassiana spore germination at various temperatures. Tween20 and Tween80 were compatible with all the B. bassiana isolates in the germination studies, but inhibited germination at higher surfactant concentrations, irrespective of the conidial concentrations. Breakthru® had an inhibitory effect on germination even at the lowest concentration of 0.1% on all the B. bassiana isolates. The effects of the surfactants on spore germination did not correspond with their effects on colony growth. Conidial viability within the same formulation declined significantly with increases in temperature, irrespective of the surfactant. The optimal temperature for conidial germination of B. bassiana isolates was approximately 25 °C with an upper limit at 30 °C. Isolate 7320 was identified as the least affected by the different surfactants. This isolate was able to germinate rapidly in a broad temperature range of 25–30 °C after 24 h, this characteristic being an essential factor in controlling house fly populations in poultry houses.