Naja ashei is a snake of medical importance in Kenya, Ethiopia, Somalia, Uganda, and Tanzania. Little is known about the enzymatic (snake venom phospholipases A
; svPLA
's) and toxic (lethal) ...activities of N. ashei venom and crucially, the safety and capacity of available antivenom to neutralize these effects. This study aimed to determine the enzymatic and toxic activities of N. ashei venom and the capacity of Indian and Mexican manufactured antivenoms to neutralize these effects. The protein content of the venom and the test antivenoms were also evaluated. A 12-point log concentration-response curve (0.5-22.5 µg/mL) was generated on an agarose-egg yolk model to predict the svPLA
activity of the venom. The toxicity profiles of the venom and antivenoms were evaluated in the brine shrimp lethality assay. Lowry's method was used for protein estimation.
Low and intermediate concentrations of the venom exhibited similar svPLA
activities. The same was true for concentrations > 15 µg/mL. Intermediate and high doses of the venom exhibited similar mortalities in brine shrimp and test antivenoms were generally non-toxic but poorly neutralized svPLA
activity. Mexican manufactured antivenom had lower protein content but neutralized venom-induced brine shrimp lethality much more effectively than Indian manufactured antivenom.
Lethality and cytotoxicity assays of snake venoms and their neutralization by antivenom require many mice for the experiments. Recent developments have prompted researchers to seek alternative ...strategies that minimize the use of mice in line with Russel and Burch's 3Rs philosophy (Replacement, Reduction, and Refinement). Artemia salina is an animal model widely used for toxicity screening. However, its use in snake venom toxinology is limited by a lack of data. The present study compared the toxicity of venoms from Bitis arietans, Naja ashei, and Naja subfulva using mice and Artemia salina. In the Artemia salina test at 24 h and the dermonecrotic test in mice, the toxicity of the venoms was in the order Naja ashei ~ Naja subfulva > Bitis arietans. In the lethality test in mice, the toxicity of the venoms was in the order Naja subfulva > Naja ashei > Bitis arietans. These findings suggest that the toxicity of the venoms in Artemia salina and the dermonecrotic bioassay in mice have a similar trend but differ from the lethality test in mice. Therefore, it may be relevant to further explore the Artemia salina bioassay as a potential surrogate test of dermonecrosis in mice. Studies with more venoms may be needed to establish the correlation between the Artemia salina bioassay and the dermonecrotic assay in mice.
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•Bitis arietans, Naja ashei, and Naja subfulva snake venom-induced toxicities were compared in Artemia salina and in mice.•Venom-induced toxicity in Artemia salina has a similar trend to necrosis in mice but not lethality.•The Artemia salina bioassay may be further explored along the 3Rs (Reduction, Replacement, and Refinement) concept.
Snake bites are a silent public health problem in Kenya. Previous studies on snake bites in the country have mainly focused on identifying offending snake species, assessing the severity of ...envenomation and testing the efficacy of antivenom. Factors associated with snake bites in the country are yet to be fully understood. The aim of this work was to determine pharmaco-epidemiological factors associated with snake bites in areas of Kenya where incidence, severity and species responsible for snake bites have been reported.
Kakamega provincial hospital, Kabarnet, Kapenguria and, Makueni district hospitals were selected as study sites based on previous findings on incidence, severity and species responsible for snake bites in catchment areas of these hospitals. Persistent newspaper reports of snake bites in these areas and distribution of snakes in Kenya were also considered. Cases of snake bites reported between 2007-2009 were retrospectively reviewed and data on incidence, age, site of the bites, time of bite and antivenom use was collected.
176 bites were captured, 91 of which occurred in 2009. Individual incidence was between 2.7/100,000/year and 6.7/100,000/year. Bites peaked in the 1-15 year age group while 132/176 bites were in the lower limb area and 49/176 victims received antivenom. Most bites occurred during the dry season, in the bush and in the evening. Overall mortality was 2.27%.
There is a need to sensitize the Kenyan public and healthcare personnel on preventive measures, first aid and treatment of snake bites.
This study aimed to determine the efficacy of Inoserp, Vins bioproducts, and South African Institute of Medical Research (SAIMR) polyvalent antivenoms in neutralizing Naja ashei venom-induced ...lethality in mice. The neutralization efficacy of the antivenoms were expressed as effective dose, median effective ratio, potency, normalized potency, volume, and the number of vials of antivenom required to neutralize 100 mg of Naja ashei venom (NAV).
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•Naja ashei venom (NAV) has an i.p. LD50 of 3.02 (2.45–3.72) μg/g in mice.•Vins bioproducts antivenom has poor efficacy against NAV-induced lethality.•Inoserp and South African Institute of Medical Research polyvalent antivenoms have high potency in NAV-induced lethality.
Background: Data on the cost of snakebite injuries may inform key pillars of universal health coverage including proper planning, allocation, and utility of resources. This study evaluated the ...injuries, management, and costs resulting from snakebites at Jaramogi Oginga Odinga Teaching and Referral Hospital (JOOTRH) in Kenya.
Methods: In total, medical records of 127 snakebite victims attending JOOTRH between January 2011 and December 2016 were purposely selected and data on the age, gender, type of residence (urban or rural), part of the body bitten, time of bite, injuries, pre-hospital first aid, time to hospital, length of stay, treatment, and costs were collected. Regression analysis was used to predict the total indirect cost of snakebite injuries and
p≤ 0.05 was considered significant. Mortality and loss of income of hospitalized victims were considered as direct costs.
Results: It was found that 43 victims were 13-24 years of age, 64 were female, 94 were from rural areas, 92 were bitten on the lower limbs, 49 were bitten between 6.00 pm and midnight, 43 attempted pre-hospital first aid, and the median time to hospital was 4.5 hours. Antivenom, supportive therapy, antibiotics, antihistamines, corticosteroids, analgesics, and non-steroidal anti-inflammatory drugs were used. Cellulitis, compartment syndrome, gangrenous foot, psychiatric disorder, and death were the main complications. Most victims spent 1-5 days in hospital and the median cost of treating a snakebite was 2652 KES (~$26). Drugs, ward charges, and nursing procedures were the highest contributors to the total indirect cost. Victims hospitalized for 6-10 days and >10 days incurred 32% and 62% more costs, respectively, compared to those hospitalized for 1-5 days.
Conclusions: The longer snakebite victims are hospitalized, the higher the cost incurred. Continuous medical education on the correct management of snakebites should be encouraged to minimize complications that may increase hospital stays and costs incurred.
The black mamba is a common snake in Sub-Saharan Africa, a region with a high burden of snakebite envenoming. Differences in the composition and toxicity of the venom of this snake as one moves from ...one region to another within Sub-Saharan Africa, and the variations in manufacturing protocols by different antivenom producers may result in antivenom products of unknown efficacy. This variability may compromise the management of venomous snakebite in the region including those of the black mamba. Therefore, testing the antidotal efficacy of the antivenoms indicated for black mamba venom is warranted. The aim of the present study was to determine the efficacy of two antivenoms routinely used in some hospitals in Kenya between 2009 and 2011.The moving average interpolation method of Weil was used to determine the acute intraperitoneal (i.p) median lethal dose (LD50) of black mamba venom in mice. Symptoms of envenomation and the effects of the venom on hematological parameters were observed. The antidotal efficacy of the two polyvalent antivenoms (antivenom I and II) was then tested against the acute i.p. LD50 of black mamba venom.The acute i.p. LD50 of the whole venom of black mamba in mice was found to be 0.341 mg/kg. Antivenom I afforded 80% protection to mice experimentally envenomed with a 3 LD50 dose of black mamba venom while antivenom II afforded 60% protection to mice experimentally envenomed with a 3 LD50 dose of black mamba venom. Additionally, antivenom II also afforded 40% protection to mice experimentally envenomed with a 4 LD50 dose of black mamba venom. Analgesia, weakness, and altered respiration were observed as neurotoxic symptoms.The LD50 of black mamba venom in mice by the intraperitoneal route is low. Moreover, the data also suggests that the antivenoms tested during the study period had varying efficacy in neutralizing black mamba envenomation in mice. Keywords: Snakebite, Snakebite envenoming, Black mamba, Dendroaspis polylepis, Lethality, Antivenom, Kenya
The black mamba (
) ranks consistently as one of the most revered snakes in sub-Saharan Africa. It has potent neurotoxic venom, and envenomation results in rapid onset and severe clinical ...manifestations. This report describes the clinical course and reversal of effects of black mamba envenomation in a 13-year-old boy in the Jimba area of Malindi. The victim presented to Watamu Hospital, a low resource health facility with labored breathing, frothing at the mouth, severe ptosis and pupils non-responsive to light. His blood pressure was unrecordable, heart rate was 100 beats per minute but thready, his temperature was 35.5 °C, and oxygen saturation was 83%. Management involved suction to clear salivary secretions, several hours of mechanical ventilation via ambu-bagging, oxygen saturation monitoring, and the use of South African Vaccine Producers (SAVP) polyvalent antivenom. Subcutaneous adrenaline was used to stave off anaphylaxis. The victim went into cardiac arrest on two occasions and chest compressions lasting 3⁻5 min was used to complement artificial ventilation. Hemodynamic instability was corrected using IV infusion of ringers lactate and normal saline (three liters over 24 h). Adequate mechanical ventilation and the use of specific antivenom remain key in the management of black mamba envenomation.
The emergency department (ED) of the Jaramogi Oginga Odinga Teaching and Referral Hospital (JOOTRH) handles many cases of poisoning. However, there is scant information on the factors, agents, and ...outcomes of poisoning at the hospital. The aim of this work was to determine the factors, agents, and outcomes of poisoning at JOOTRH. Records of patients who presented to JOOTRH with symptoms of poisoning between January 2011 and December 2016 were retrieved. Data on age, gender, offending agents, time, and season of exposure were collected. Information on the route of exposure, motive, and clinical symptoms of poisoning was also included. Other information included the laboratory evaluation, first aid measures, period of hospitalization, and outcome of poisoning. Mean, standard deviation, frequencies and bar graphs were used to describe the demographic factors of the study population. Multivariate logistic regression was used to determine the strength of association between risk factors and outcome of poisoning among patients. The level of significance for inferential analysis was set at 5%. There were 385 cases of poisoning: 57.9% (223/385) were male, 31.9% (123/385) were 13⁻24 years of age, and 83.9% (323/385) of exposures were in Kisumu County. The peak time of exposure was 6:00⁻00:00, and 23.6% (91/385) presented 1⁻4 h after exposure. About 62.9% (242/385) of the cases were due to accidental poisoning. Snakebites and organophosphates (OPPs) contributed to 33.0% (127/385) and 22.1% (85/385) of all cases, respectively. About 62.1% (239/385) of exposures were oral, and 63.9% (246/385) of all cases occurred in the rainy season. Additionally, 49.2% (60/122) of intentional poisoning was due to family disputes, and 16.1% (10/62) of pre-hospital first aid involved the use of tourniquets and herbal medicine. About 28.6% (110/385) of the victims were subjected to laboratory evaluation and 83.9% (323/385) were hospitalized for between 1⁻5 days. Other results indicated that 80.0% (308/385) responded well to therapy, while 7.3% (28/385) died, 68% (19/28) of whom were male. Furthermore, 39.3% (11/28) of the deaths were related to OPPs. Our findings suggest that the earlier the victims of poisoning get to the hospital, the more likely they are to survive after treatment is initiated. Similarly, victims of poisoning due to parental negligence are more likely to survive after treatment compared to other causes of poisoning, including family disputes, love affairs, snakebites, and psychiatric disorders. The management of JOOTRH should consider allocating resources to support the development of poison management and control.
Complementary and alternative medicine is an integral component of primary healthcare in Kenya. This is because the infrastructural health setup in the country is inadequate in catering for all the ...medical needs of the population. This particularly holds true in the rural areas where many rural folk rely on products of herbal origin to offset their healthcare needs. More often than not these products are an elaborate cacophony of several different substances of biological origin and thus need personnel adept in their preparation. Sadly, due to loopholes in legislation and regulation, quacks have a field day in the practice. Moreover, the process of planting, harvesting, preparation and storage of herbs and related products dictates that a significant number of people will ultimately be involved in the whole process. This is likely to set the stage for manipulation and compromise of the safety, quality and efficacy of these products. This state of affairs appears unabated especially in the context of the current legal and regulatory framework governing herbal medicine use and practice in Kenya. Not only are these laws inadequate, they are shrouded in ambiguity, open to interpretation and the authorities mandated to implement them often end up performing duplicate roles. The aim of this review is to critique the legal and regulatory provisions governing herbal medicine use and practice in Kenya. In conclusion, laws and regulations meant to control herbal medicine use and practice in Kenya are wanting. Clear and definitive legislation on herbal medicine use and practice coupled with effective implementation by mandated institutions will go a long way in inspiring confidence to all stakeholders of herbal medicine.
Background
Artesunate-amodiaquine (AS-AQ) is an antimalarial drug. It is associated with improved cure rates, accelerated response to therapy and delayed development of resistance. However, liver ...damage, neurotoxicity and agranulocytosis have been reported as adverse effects whose origins have been linked to free radicals generated by the drug. According to native
materia medica
,
Moringa oleifera (MO)
has wide utility in ethnomedicine. However, there is paucity of information on the hepatoprotective efficacy of this plant. The present study evaluated the mitigative effects of
MO
leaf extracts against liver injury induced by AS-AQ combination in female
Wistar
rats.
Methods
Dry leaf powder of
MO
was extracted with water and a 20:80
v
/v mixture of water and methanol to give aqueous (AQ) and aqueous-methanol (AQ-ME)
MO
leaf extracts respectively. In vitro hydroxyl free radical scavenging activity of serial dilutions (10–100 μg/ml) of each of the extracts was then evaluated using an assay model where butylated hydroxytoluene (BHT) served as a reference standard. The extract with better free radical scavenging activity was then evaluated for hepatoprotective effects against AS-AQ intoxication in female
Wistar
rats based on the Acute Toxic Class method (OECD 2000). Serum asparate amino transferase (AST), alanine amino transferase (ALT), total bilirubin and histological examination of rat liver sections were used to evaluate the hepatoprotective activity of the selected
MO
leaf extract. Siliphos
®
(standard hepatoprotectant) was used for comparison.
Results
There was a concentration dependent increase in the hydroxyl free radical scavenging activity of
MO
leaf extracts and standard (BHT) with values ranging from 46.36–66.36% for the AQ extract, 41.04–60.95% for the AQ-ME extract and 44.93–65.23% for BHT with corresponding IC
50
values of 26.84 μg/ml, 51.88 μg/ml and 32.58 μg/ml respectively. A 1000 mg/kg dose of the AQ-ME
MO
leaf extract significantly (
p < 0.05
) lowered AST values of AS-AQ intoxicated rats to a level comparable to the standard hepatoprotectant; Siliphos
®
. Serum ALT and TB were also lowered but this was not statistically significant
(p > 0.05)
. The 1000 mg/kg dose also reduced hepatocyte degeneration in rats treated with four times the clinical dose of AS-AQ. This study suggests that the hepatoprotective activity of the leaves of
MO
may have some relation to its free radical scavenging properties. These leaves may thus be useful in mitigating free radical initiated disease conditions.
Conclusion
The aqueous-methanol
Moringa oleifera
leaf extract exhibits free radical scavenging and hepatoprotective properties. Further investigations on the structural identity of the phytoconstituents and their mechanisms of action should be performed to facilitate the development of a potent medicinal agent.
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