Challenges in the control of neglected insect vector diseases of human importance in the Anglo-Caribbean.

INTRODUCTION: Neglected tropical diseases (NTDs) in developing countries like the Caribbean, negatively affect multiple income-generating sectors, including the tourism industry upon which island states are highly dependent. Insect-transmitted NTDs include, but are not limited to, malaria, dengue and lymphatic filariasis. Control measures for these disease, are often ignored because of the associated cost. Many of the developing country members are thus retained in a financially crippling cycle, balancing the cost of prophylactic measures with that of controlling an outbreak.The purpose of the paper is to bring awareness to NTDs transmitted by insects of importance to humans, and to assess factors affecting such control, in the English-speaking Caribbean. METHOD: Comprehensive literature review on reports pertaining to NTDs transmitted by insects in the Caribbean and Latin America was conducted. Data search was carried out on PubMed, and WHO and PAHO websites. RESULTS AND CONCLUSION: Potential risk factors for NTDs transmitted by arthropods in the English-speaking Caribbean are summarised. The mosquito appears to be the main insect-vector of human importance within the region of concern. Arthropod-vectors of diseases of veterinary importance are also relevant because they affect the livelihood of farmers, in highly agriculture based economies. Other NTDs may also be in circulation gauged by the presence of antibodies in Caribbean individuals. However, routine diagnostic tests for specific diseases are expensive and tests may not be conducted when diseases are not prevalent in the population. It appears that only a few English-speaking Caribbean countries have examined secondary reservoirs of pathogens or assessed the effectivity of their insect control methods. As such, disease risk assessment appears incomplete. Although continuous control is financially demanding, an integrated and multisectoral approach might help to deflect the cost. Such interventions are now being promoted by health agencies within the region and various countries are creating and exploring the use of novel tools to be incorporated in their insect-vector control programmes.

The Isolation of Hypoglycaemic Compounds from Desmodium canum and Their Synergistic Effect on Blood Glucose Levels in Euglycaemic Sprague Dawley Rats.

Desmodium canum (Strong back) commonly consumed as a tea or tonic is believed to possess hypoglycaemic activity. This paper sets out to isolate potential hypoglycaemic compounds present within the plant and investigate their synergistic effects on blood glucose levels in euglycaemic Sprague Dawley rats. The milled plant was sequentially extracted using hexane, ethyl acetate and methanol. The ethyl acetate extract was subjected to column chromatography yielding seven major fractions and were subsequently bioassayed using the Oral Glucose Tolerance Test (OGTT). Further chromatographic separation and analysis using Gas Chromatography-Mass Spectroscopy and Fourier Transform Infrared Spectroscopy enabled the identification of two hypoglycaemic compounds, oleic acid (OA) and succinic acid (SA). These were bioassayed individually and as a cocktail to determine the synergistic effects using OGTT. Intravenous administration of these compounds individually indicated both are very potent in retarding blood glucose levels. However, the most significant activity was observed on synergistic administration. The cocktail (1 : 1) displayed significant hypoglycaemic activity throughout the entire study. It also significantly differed from OA at the 120 min interval (3.43 ± 0.22 mmol/L vs. 4.98 ± 0.19 mmol/L, resp., p=4.29 × 10-7) and significantly differed from SA at 30 min (3.95 ± 0.43 mmol/L vs. 5.17 ± 0.32 mmol/L, resp., p=0.003), 90 min (4.35 ± 0.36 mmol/L vs. 5.49 ± 0.69 mmol/L, resp., p=0.04), and 120 min intervals (3.43 ± 0.22 mmol/L vs. 4.94 ± 0.31, resp., p=1.54 × 10-5). Oral administration of the cocktail showed comparable potency to that of metformin (p > 0.05) throughout the OGTT curve. The synergistic effects of the naturally isolated compounds yielded higher potency levels than individual administration and when administered orally, the hypoglycaemic effect was similar to that of metformin. This may assist in paving a way to attempt a novel method in approaching antidiabetic therapy.

Prevalence of injuries and reporting of accidents among health care workers at the University Hospital of the West Indies.

OBJECTIVES: This study investigated the knowledge, awareness and practices of health care workers towards universal precautions at the University Hospital of the West Indies. The study also examined the prevalence of injuries experienced by health care workers, as well as incidence of accidents and compliance with post-exposure prophylaxis. MATERIALS AND METHODS: A cross sectional survey was conducted in September and October 2007. A 28-item self-administered questionnaire was provided to two hundred health care workers including medical doctors, medical technologists, nurses and porters to assess knowledge and practices regarding universal precautions, prevalence of injuries and incidence of accidents. RESULTS: Almost two-thirds (62.3%) of the respondents were aware of policies and procedures for reporting accidents while one-third (33.2%) were unsure. All nurses were aware of policies and procedures for reporting accidents, followed by medical doctors (88%) and medical technologists (61.2%). The majority (81.5%) of the respondents experienced splashes from bodily fluid. Over three-quarters of medical doctors (78%) and two-thirds of nurses (64%) reported having experienced needle stick injuries, while the incidence among medical technologists was remarkably lower (26%). The majority of the respondents (59%) experienced low accident incidence while just over one-tenth (14%) reported high incidence. Eighty four respondents reported needle stick injuries; just under two-thirds (59.5%) of this group received post-exposure treatment. CONCLUSIONS: The study found that majority of health care workers were aware of policies and procedures for reporting accidents. Splashes from body fluids, needle stick injuries and cuts from other objects were quite prevalent among health care workers. There is a need for monitoring systems which would provide accurate information on the magnitude of needle stick injuries and trends over time, potential risk factors, emerging new problems, and the effectiveness of interventions at The University Hospital of the West Indies and other hospitals in Jamaica.

Hypoglycaemic effect of stigmast-4-en-3-one and its corresponding alcohol from the bark of Anacardium occidentale (cashew).

Intravenous administration of the hexane extract of the bark of Anacardium occidentale (cashew) in normal, healthy dogs produced a significant lowering of the blood glucose levels. Pursuit of the hypoglycaemic principle(s) in the hexane extract resulted in the isolation and characterization of two compounds, stigmast-4-en-3-ol (1) and stigmast-4-en-3-one (2). These compounds were purified by chromatographic methods and the structures were characterized by spectroscopic methods. Both compounds produced significant hypoglycaemic activity after intravenous administration at a dose of 1.3 mg/kg body weight. The bark of the cashew plant, A. occidentale, exhibited a hypoglycaemic effect probably due to the presence of these compounds.