Development and validation of a rapid epidemiological assessment tool for lymphatic filariasis.

The real burden of lymphatic filariasis in most endemic areas remain unknown even though it is a major public health problems in many tropical countries. This is particularly so in sub-Saharan Africa, primarily because the standard procedures for assessing communities at risk of the disease are cumbersome, time-consuming, expensive and very intrusive. The nocturnal periodicity of the parasite requires parasitological examinations to be done at night and thus it becomes logistically cumbersome to organize. As a result of the lack of data on the burden and distribution of the disease, health care managers do not put much priority on its control. The need to develop instruments which are easy to use in the field to identify communities at risk is therefore paramount for the initiation of any control programme. The aim of this study was to develop and validate rapid epidemiological assessment tools for the community diagnosis of lymphatic filariasis, and in the future, use the tools to determine the distribution of the disease, identify high risk communities, and obtain sufficient information for planning a control programme in Ghana. The data collection methods used were: • Key informant interviews and other qualitative data collection methods, • Physical examination of a sampled population by trained health workers, and • Filarial surface antigen assays of those who were physically examined. These methods were validated using standard epidemiological techniques such as: • Physician examination of the same individuals who were examined by the health worker, and, • Night blood parasitological examination of the same individuals who had the antigen assays done on them. The key informant interviews were qualitatively very useful in identifying communities at risk, and tracing people with overt chronic disease. The system of sending questionnaires through routine administrative systems worked very well. The return rate of the questionnaires was about 95%. The District Assemblies provided reliable information on the communities, but teachers provide more accurate figures when compared with existing data from those communities. Routine reports from health institutions, even though useful, grossly under estimated the burden of the disease in the community. This is because these reports were influenced by: • physical accessibility and ability to pay for the services, • socio-cultural beliefs associated with the disease, • technical expertise and laboratory facilities available at the institution, and • the quality of record keeping. The prevalence of hydroceles was high in the communities (range = 4.5 - 40.75%, mean = 17.78%). The community microfilaria prevalence correlated very well with the community prevalence of hydroceles (r = 0.84). There was a generally high agreement between the health worker's clinical findings and that of the physician (Kappa>0.85 in most instances). The prevalence of infection detected by the Og4C3 surface antigen was consistently lower than the standard night blood smears in all the 20 communities. Thus, even though the antigen test had been shown in the laboratory to have a sensitivity of about 99% and specificity of a similar value, it was not possible to replicate such a high sensitivity under field conditions using blood collected on filter paper. The findings of the study suggested that it is possible to obtain reliable and valid estimates of the burden of lymphatic filariasis at community level using a combination of cheap and non-invasive methods such as: • Key person interviews, • Examination of a random sample of the population by peripheral level health staff. The antigen assays will however require further development for field use

On farm evaluation of the contribution of three green manures to maize yield in the semi-deciduous forest zone of Ghana

Low soil fertility is one of the major factors responsible for low crop yields on small-scale farms in Africa. The use of Chromolaena odorata, Crotalaria juncea and Panicum maximum and their combination with NPK for improving soil fertility and maize yield was investigated in the semideciduous forest zone of Ghana. Each plant material was applied at two application rates, 1 and 3 t ha-1. The field design was a randomized complete block with three replications. The plant materials caused an initial immobilization of nutrients which negatively affected maize grain yield in the major season. The plant materials plus N45P30K60 however, was able to provide nutrients that were sufficient to increase maize yields by over 85% relative to the control for the two consecutive seasons. N90P60K60 application alone produced the highest grain yield of 4.65 t ha-1 in the major season but less so in the minor season. Maize grain yield was not influenced by the quantity of plant materials application but was higher during the minor season than in the major season. The results of the study provide soil fertility management options for sustainable food production in the semi-deciduous forest zone of Ghana. Key words: Fertilizer, maize, organic residues, soil fertility

Effect of site characteristics on the productivity and economic returns from cassava legume intercropping in Ghana

In a 2-year field study, cassava was intercropped with four legumes (cowpea, pigeon pea, soyabean and Stylosanthes at three locations with different soil and environmental conditions, to determine the effect of site characteristics on the agronomic and economic advantage of the intercrop. The trial was a factorial experiment in a split plot design with three replications. A cost benefit analysis was conducted for the trial on the different crop arrangements. Root yield of cassava in the mixed cassava legume treatment across location during the first year was significantly higher (p < 0.05) compared to the stripped treatment. Root yield of cassava cowpea mixed intercrop for example ranged from 38 to 88 t/ha. In the second year however, considerable variations were observed among the treatments with NPK treatment giving the highest yield of 84 t/ha. This influenced the overall economic net benefits and showed that the intercrop advantage depended on the interaction of component crops, the growth environment and to some extent agronomic manipulations, suggesting that the best combination of crops under a particular system of management in one environment with a particular set of climate and soil conditions may not necessarily be suitable in another environment

High coverage of mass drug administration for lymphatic filariasis in rural and non-rural settings in the Western Area, Sierra Leone

<p>Abstract</p> <p>Background</p> <p>Lymphatic filariasis elimination programs are based upon preventative chemotherapy annually in populations with prevalence more than or equal to 1%. The goal is to treat 80% of the eligible, at risk population yearly, for at least 5 years, in order to interrupt transmission and prevent children from becoming infected. This level of coverage has been a challenge in urban settings. Assessing the coverage in a rapidly growing urban/non-rural setting with inadequate population data is also problematic. In Sierra Leone, a 5-day preventative chemotherapy campaign was carried out in the Western Area including the capital: Freetown. An intensive, social mobilization strategy combined traditional and modern communication channels. To aid dissemination of appropriate information Frequently Asked Questions were developed and widely circulated. The population of the Western Area has grown faster than projected by the 2004 National Census due to the post-war settlement of internally displaced persons. As a reliable denominator was not available, independent monitoring was adapted and performed "in process" to aid program performance and "end process" to assess final coverage.</p> <p>Results</p> <p>In 5 days 1,104,407 eligible persons were treated. Using the projected population from the 2004 census this figure represented coverage of 116% in the Urban Western Area and 129% in the Rural Western Area. Independent monitors interviewed a total of 9,253 persons during the 2 End Process days representing 1% of the projected population. Of these, 85.8% recalled taking both ivermectin and albendazole (Urban: 85.2%, Rural: 87.1%). No serious adverse drug reactions were reported.</p> <p>Conclusion</p> <p>The paper presents the key elements of success of the social mobilization and implementation strategy and describes the independent monitoring used to estimate final coverage in this urban/non-rural setting where the current population size is uncertain. This implementation strategy and Independent Monitoring tool could be useful in similar, rapidly growing cities implementing lymphatic filariasis elimination programs.</p

Spatial distribution of podoconiosis in relation to environmental factors in Ethiopia: a historical review

BACKGROUND An up-to-date and reliable map of podoconiosis is needed to design geographically targeted and cost-effective intervention in Ethiopia. Identifying the ecological correlates of the distribution of podoconiosis is the first step for distribution and risk maps. The objective of this study was to investigate the spatial distribution and ecological correlates of podoconiosis using historical and contemporary survey data. METHODS Data on the observed prevalence of podoconiosis were abstracted from published and unpublished literature into a standardized database, according to strict inclusion and exclusion criteria. In total, 10 studies conducted between 1969 and 2012 were included, and data were available for 401,674 individuals older than 15 years of age from 229 locations. A range of high resolution environmental factors were investigated to determine their association with podoconiosis prevalence, using logistic regression. RESULTS The prevalence of podoconiosis in Ethiopia was estimated at 3.4% (95% CI 3.3%-3.4%) with marked regional variation. We identified significant associations between mean annual Land Surface Temperature (LST), mean annual precipitation, topography of the land and fine soil texture and high prevalence of podoconiosis. The derived maps indicate both widespread occurrence of podoconiosis and a marked variability in prevalence of podoconiosis, with prevalence typically highest at altitudes >1500 m above sea level (masl), with >1500 mm annual rainfall and mean annual LST of 19-21°C. No (or very little) podoconiosis occurred at altitudes 24°C. CONCLUSION Podoconiosis remains a public health problem in Ethiopia over considerable areas of the country, but exhibits marked geographical variation associated in part with key environmental factors. This is work in progress and the results presented here will be refined in future work

The argument for integrating vector control with multiple drug administration campaigns to ensure elimination of lymphatic filariasis

BACKGROUND: There is a danger that mass drug administration campaigns may fail to maintain adequate treatment coverage to achieve lymphatic filariasis elimination. Hence, additional measures to suppress transmission might be needed to ensure the success of the Global Program for the Elimination of Lymphatic Filariasis. DISCUSSION: Vector control successfully eliminated lymphatic filariasis when implemented alone or with mass drug administration. Challenges to lymphatic filariasis elimination include uncertainty of the exact level and duration of microfilarial suppression required for elimination, the mobility of infected individuals, consistent non-participation of some infected individuals with mass drug administration, the possible development of anti-filarial drug resistance and treatment strategies in areas co-endemic with loasis. Integration of vector control with mass drug administration can address some of these challenges. The potential benefits of vector control would include: (1) the ability to suppress filariasis transmission without the need to identify all individual 'foci of infection'; (2) minimizing the risk of reestablishment of transmission from imported microfilaria positive individuals; and (3) decreasing the risk of dengue or malaria transmission where, respectively, Aedes or Anopheles are lymphatic filariasis vectors. SUMMARY: With adequate sustained treatment coverage, mass drug administration should meet the criteria for elimination of lymphatic filariasis. However, it may be difficult to sustain sufficiently high mass drug administration coverage to achieve lymphatic filariasis elimination in some areas, particularly, where Aedes species are the vectors. Since vector control was effective in controlling and even eliminating lymphatic filariasis transmission, integration of vector control with mass drug administration will ensure the sustainability of transmission suppression and thereby better ensure the success of national filariasis elimination programs. Although trials of some vector control interventions are needed, proven vector control strategies are ready for immediate integration with mass drug administration for many important vectors. Vector control is the only presently available additional lymphatic filariasis control measure with the potential for immediate implementation

Resource Planning for Neglected Tropical Disease (NTD) Control Programs: Feasibility Study of the Tool for Integrated Planning and Costing (TIPAC).

<p>Resource Planning for Neglected Tropical Disease (NTD) Control Programs: Feasibility Study of the Tool for Integrated Planning and Costing (TIPAC)</p