Attenuation of salt-induced hypertension by aqueous calyx extract of Hibiscus sabdariffa

The aqueous calyx extract of Hibiscus sabdariffa (HS) has a folk reputation as an antihypertensive agent. On account of its antioxidant properties and probably high K+ concentration, we hypothesized that HS may attenuate the development of salt-induced hypertension. Sprague-Dawley rats (n=8 each) were treated for 12 weeks as follows: control (normal diet + water), salt-loaded (8% salt diet + water), HS (normal diet + 6 mg/ml HS), salt+HS (8% salt diet + 6 mg/ml HS) and furosemide (normal diet+ 0.25mg/Kg furosemide). Their blood pressure and heart rates were measured and responses to noradrenalin and acetylcholine (0.01 mg/kg respectively) were estimated. The cationic concentration of 6 mg/ml HS was determined. The Na+ and K+ concentrations of 6 mg/ml HS were 3.6 and 840 mmol/l respectively. The mean arterial pressure (MAP±SEM; mmHg) of salt loaded rats (184.6±29.8) was significantly higher than control (113.2±3.0; P<0.05), HS (90.0±7.4; P<0.001) salt+HS (119.4±8.9; P<0.05) and furosemide (94.9±11.5; P<0.01). The MAP of salt+HS and control rats did not differ significantly and the effect of HS was comparable to furosemide. The pressor response to noradrenalin or vasodilator response to acetylcholine remained similar in all groups. These results suggest that HS attenuated the development of salt-induced hypertension and this attenuation may be associated with its high K+ content or high potassium: sodium ratio and not with altered pressor/depressor response to noradrenalin or acetylcholine. Also the effects of HS and furosemide on blood pressure are comparable.

Community-directed treatment of onchocerciasis with ivermectin in Takum, Nigeria

A study to identify factors within the community that can ensure sustainable community-directed treatment (ComDT) with ivermectin compared the effectiveness of programme-designed (PD) and community-designed (CD) strategies in 37 villages in the Takum area of Nigeria. In a subset of PD villages, designated PD1, communities were asked to use the village heads as community-directed distributors (CDD), and the other communities (PD2) were asked to select female distributors, and both were instructed to use the house-to-house method of distribution. Community-designed communities, on the other hand, were asked to design their own approach. All study communities received health education, treatment guidelines, and training enabling them to determine appropriate dosage. A total of 1744 people were interviewed about their experiences after two treatment cycles. Communities preferred honest, reliable community members as CDDs, but few women were selected. The results show striking similarity between PD and CD villages in many respects. In the PD1 villages, where the programme designated the village head as CDD, the mode of distribution was changed from house-to-house to central point, and distribution took place in the compound of the village head. In the PD2 villages, where the programme specified distributors should be women, the women who were selected were replaced by their male children. These changes to the original design were consistent with the local cultural norms and made the arrangement for distribution more acceptable to the people. Programme-designed villages that used the village head as distributors performed better than those that used women, and the coverage in the former group compares well with that of CD villages. Only five villages achieved coverage > 60%, but dosage was correct in most cases (87.4%). Drug shortage was the most frequent reason for non-treatment. Communities devised means for ensuring equity and fairness in sharing their limited supply and freely altered the original designs to fit local norms and values. These changes to the original design were consistent with local norms and were acceptable to the people. The success of this strategy should be tested in other parts of Nigeria. Long-term success of ComDT, however, requires a reliable drug supply and inputs from professionals in the health system for minimal supervision. The core issues that determine sustainability of ComDT appear to be not so much in the structure, but in the process by which they are introduced. Communities will only sustain a programme where the process of implementation fits well with local norms and where communities are free to alter PD procedures that are inconsistent with local customs.

Community-perceived benefits of ivermectin treatment in northeastern Nigeria

A 3-step approach involving focus group discussion, structured interviews and informal conversations with key individuals was used to investigate community usage and perceived benefits of ivermectin in nine Nigerian villages participating in a WHO-sponsored investigation of community-directed treatment with ivermectin (CDTI). Only 27% of 284 persons interviewed had received treatment. An under-estimation of the district's ivermectin needs led to inadequate supply of ivermectin to the communities, which was cited as the main reason (65%) for non-treatment. All those treated (N=76) were further interviewed using questionnaires. Worm expulsion (80%) and blindness prevention (68%) were the most frequently stated benefits. Other perceived benefits were an increase in vitality (68%), sexual drive and performance (29%). The sudden relief from a heavy burden of worms, which had built up over a long period, may have indirect effect on all aspects of an individual's health and account for the diverse experiences. The feeling of vitality, good appetite and general health following ivermectin treatment is an animating experience to many communities. Health planners face the challenge of preparing communities for fewer 'sensational' experiences and preventing a possible feeling of disappointment that may result from frequent usage.