Short communication: impact of long-term (14 years) bi-annual ivermectin treatment on Wuchereria bancrofti microfilaraemia.

Ivermectin has been and continues to be extensively used to control onchocerciasis in areas of hyper and mesoendemicity within the African Programme of Onchocerciasis Control. As programmes to eliminate lymphatic filariasis (LF) caused by Wuchereria bancrofti expand, areas of coendemicity with onchocerciasis will be incorporated into LF programmes. This study reports that in villages which were hyperendemic for onchocerciasis after some 14 years of treatment with ivermectin, no W. bancrofti could be detected in a population of 1210 individuals whilst in adjacent villages a prevalence of around 3% was found. Despite the long period of ivermectin treatment Mansonella perstans did not appear to respond to ivermectin in this setting.

Impact of long-term ivermectin (Mectizan) on Wuchereria bancrofti and Mansonella perstans infections in Burkina Faso: strategic and policy implications.

Parasitological and clinical surveys were used to determine the long-term impact of ivermectin on the prevalence of Wuchereria bancrofti and Mansonella perstans filarial infections, when the drug was given under community-directed-treatment strategies for onchocerciasis control. The study was undertaken in 11 communities in south-western Burkina Faso. Six of the villages investigated had been treated with ivermectin at least once a year for five of 6 years, with a mean coverage of approximately 65% in each round. The other five, adjacent villages, which were matched with the ivermectin-treated communities by size, ethnicity and social and economic activities, had never been treated because they were not endemic for onchocerciasis. Each subject was checked by the microscopical examination of a smear of 'night' blood, by measurement of the level of circulating antigens from adult W. bancrofti, and by clinical examination for hydrocele (if male) and lymphoedema. The prevalences of lymphoedema and hydrocele in the treated villages were similar to those in the untreated. The prevalences and intensities of W. bancrofti and M. perstans microfilaraemia were, however, significantly lower in the ivermectin-treated communities. The implications of this study are discussed in relation to the old Onchocerciasis Control Programme (OCP) and to the ongoing African Programme for Onchocerciasis (APOC), where extensive and sustained ivermectin distribution is planned through community-based treatment programmes. As with onchocerciasis in Africa, the success of annual treatments to control lymphatic filariasis will depend not only on the number of regular rounds of treatment given but on adequate coverages being achieved in each round. Wherever ivermectin is being distributed alone, for onchocerciasis control, its impact on other filarial infections, notably W. bancrofti, should be evaluated routinely. Any opportunity to add donated albendazole to such distributions should be taken, both to limit the transmission of W. bancrofti and for the wider public-health benefits.

The use of spatial analysis in mapping the distribution of bancroftian filariasis in four West African countries.

The geographical distribution of human infection with Wuchereria bancrofti was investigated in four West African countries (Benin, Burkina Faso, Ghana and Togo), using a commercial immunochromatographic test for filarial antigen. Efforts were made to cover each health-system implementation unit and to ensure no sampling point was >50 km from another, but otherwise the 401 study communities were selected at random. The aim was to enable spatial analysis of the data, to provide a prediction of the overall spatial relationships of the infection. The results, which were subjected to an independent random validation in Burkina Faso and Ghana, revealed that prevalence in the adult population of some communities exceeded 70% and that, over large areas of Burkina Faso, community prevalences were between 30% and 50%. Most of Togo, southern Benin and much of southern Ghana appeared completely free of the infection. Although there were foci on the Ghanaian coast with prevalences of 10%-30%, such high prevalences did not extend into coastal Togo or costal Benin. The prevalence map produced should be useful in prioritizing areas for filariasis control, identifying potential overlap with ivermectin-distribution activities undertaken by onchocerciasis-control programmes, and enabling inter-country and sub-regional planning to be initiated. The results indicate that bancroftian filariasis is more widely distributed in arid areas of Burkina Faso than hitherto recognized and that the prevalences of infection have remained fairly stable for at least 30 years. The campaign to eliminate lymphatic filariasis as a public-health problem in Africa will require significantly more resources (human, financial, and logistic) than previously anticipated.

Introduction of a simplified round partogram in rural maternity units: Seno province, Burkina Faso, West-Africa.

After a 3-day seminar on the utilization of a rectangular World Health Organization (WHO) version of the partogram and the round partogram, both versions were used under supervision in the maternity rooms of the Seno province, Burkina Faso, West-Africa, for 3 months. After this period a semi-standardized questionnaire was distributed among the partogram users. Using the round partogram with a plastic dial (dilatation indicator for the assessment of labour--DIAL), the two most common errors in the utilization of the rectangular partogram, incorrect recording at the initial examination and at the transition from latent to active phase, were largely avoided. Although the partogram was used in only 46.6% of all deliveries at the health unit level, 86% of the maternity staff using the partograms preferred the round partogram because of its time-saving and user-friendly qualities. Eighty-six per cent of its users felt that by starting the alert- and action-lines at a point later than that in the WHO partogram they would be able to avoid transferring patients unnecessarily. The wide acceptance of the simplified round partogram among the peripheral health units surveyed shows that the partogram would be an attractive tool for its users when it is made easy to use and a useful indicator for determining whether a patient transfer is necessary.

PIP: Introduction of a simplified round partogram to maternity units of Seno province in Burkina Faso after a 3-day seminar on the utilization of both the rectangular and round partograms was evaluated for 3 months. The development of the round partogram was based on the round partogram developed by the National University Hospital of Ouagadougou. Modifications were done on the partogram, such as the use of a plastic dial (dilation indicator for the assessment of labor-DIAL) to eliminate errors such as incorrect recording at the initial examination and at the transition from latent to active phase. It was noted that 46.6% of all deliveries used partograms and that 86% of the maternity staff preferred the use of round partograms because of their time-saving and user-friendly features. It was also noted that 86% of the users felt that starting the alert- and action-lines at a point later than that in the WHO partogram would prevent unnecessary transfer of patients. The acceptance of the simple round partogram among health units signifies the efficacy and efficiency of the partogram as an indicator for patient transfer and labor abnormalities.