Lymphatic Filariasis In Ghana Research Articles

Modelling the cost of engage & treat and test & treat strategies towards the elimination of lymphatic filariasis in Ghana.

Despite several years of LF-MDA implementation, Ghana still has some districts with mf prevalence >1%, partly due to poor treatment coverage levels resulting from non-participation in MDA. To address the challenges, we implemented an Engage & Treat (E&T) and Test & Treat (T&T) strategies for individuals who miss or refuse MDA respectively, in a hotspot district, enabling us to reach many of those who seldom, or never, take part in MDA. This financial cost study was undertaken to analyse data on the LF-MDA, E&T and T&T implementation in 2021 and the financial cost to inform the rollout of the E&T and T&T as mop-up strategies in future LF-MDAs. This costing study analysed cost data from the 2021 LF-MDA implementation activities carried out by the Neglected Tropical Diseases (NTD) programme of the Ghana Health Service and the SENTINEL study, carried out in Ahanta West district for the two interventions (i.e., E&T and T&T). The 2021 Ghana Population and Housing Census data was used to estimate the LF-MDA-eligible population. The financial cost per person treated was estimated and these costs were applied to the projected population to obtain the financial cost for subsequent years. Implementing MDA mop-up strategies either through the E&T or T&T to improve coverage comes at an additional cost to the elimination goals. For example, in 2024 the projected cost per person treated by the routine LF-MDA is estimated at US$0.83. The cost using the integrated LF-MDA and the E&T, T&T led by the NTD programme or T&T integrated into the health system was estimated at US$1.62, US$2.88, and US$2.33, respectively, for the same year. Despite the increased cost, the proposed combined LF-MDA and mop-up strategies will have a higher estimated population treated for 2024 (i.e., 1,392,211) compared to the routine LF-MDA approach (i.e., 988,470) for the same year. Combining LF-MDA with E&T/T&T mop-up strategies, despite their high costs, may provide NTD Programmes with the options of improving treatment coverage and reaching the LF elimination target sooner, given that the routine LF-MDA alone approach has been implemented for many years with some districts yet to reach the elimination targets.

An empirical analysis of the effects of schistosomiasis and lymphatic filariasis on macroeconomic output in Ghana

BackgroundSchistosomiasis and Lymphatic Filariasis (LF) are endemic in Ghana. These diseases cause significant morbidity and disability which can adversely affect the participation of affected persons and their caregivers in economic activities, resulting in reduced economic output at the macrolevel. This study, therefore aims to provide the first empirical evidence of the effects of these diseases on economic output at the macrolevel in Ghana. MethodsThe study uses annual time series data on Ghana collected from secondary sources over the period, 1990–2019. Gross Domestic Product (GDP) is used as the proxy for macroeconomic output (i.e., dependent variable) and the main independent variables are the point prevalence of schistosomiasis and LF (including their sex disaggregation). The Ordinary Least Square (OLS) and the Instrumental Variable Two-Stage Least Square (IV2SLS) regressions are employed as estimation techniques. ResultsUsing the OLS (IV2SLS) regressions, a percentage increase in the overall prevalence of schistosomiasis as well as the prevalence of schistosomiasis among males and females is found to be associated with a 1.37% (1.36%), 1.29% (1.30%) and 1.41% (1.39%) fall in macroeconomic output respectively, at the 1% level of significance. Similarly, a percentage increase in the overall prevalence of LF as well as the prevalence of LF among males and females is found to be associated with a 0.34% (0.37%), 0.34% (0.37%) and 0.34% (0.38%) fall in macroeconomic output respectively, at the 1% level of significance. ConclusionThere is the need to strengthen efforts towards fighting schistosomiasis and LF in Ghana in order to reduce their associated economic losses.

Evaluating context-specific evidence-based quality improvement intervention on lymphatic filariasis mass drug administration in Northern Ghana using the RE-AIM framework

BackgroundOver a decade of implementing a global strategy to eliminate lymphatic filariasis in Ghana through mass drug administration, the disease is still being transmitted in 11 districts out of an initial 98 endemic districts identified in 2000. A context-specific evidence-based quality improvement intervention was implemented in the Bole District of Northern Ghana after an initial needs assessment to improve the lymphatic filariasis mass drug administration towards eliminating the disease. Therefore, this study aimed to evaluate the process and impact of the lymphatic filariasis context-specific evidence-based quality improvement intervention in the Bole District of Northern Ghana.MethodA cross-sectional mixed methods study using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) framework to evaluate the context-specific evidence-based quality improvement intervention was employed. Quantitative secondary data was extracted from the neglected tropical diseases database. A community survey was conducted with 446 randomly selected participants. Qualitative data were collected from 42 purposively selected health workers, chiefs/opinion leaders and community drug distributors in the study area.ResultsThe evaluation findings showed an improvement in social mobilisation and sensitisation, knowledge about lymphatic filariasis and mass drug administration process, willingness to ingest the medication and adherence to the direct observation treatment strategy. We observed an increase in coverage ranging from 0.1 to 12.3% after implementing the intervention at the sub-district level and reducing self-reported adverse drug reaction. The level of reach, effectiveness and adoption at the district, sub-district and individual participants’ level suggest that the context-specific evidence-based quality improvement intervention is feasible to implement in lymphatic filariasis hotspot districts based on initial context-specific needs assessment.ConclusionThe study provided the groundwork for future application of the RE-AIM framework to evaluate the implementation of context-specific evidence-based quality improvement intervention to improve lymphatic filariasis mass drug administration towards eliminating the disease as a public health problem.

Design and Analysis of Elimination Surveys for Neglected Tropical Diseases.

As neglected tropical diseases approach elimination status, there is a need to develop efficient sampling strategies for confirmation (or not) that elimination criteria have been met. This is an inherently difficult task because the relative precision of a prevalence estimate deteriorates as prevalence decreases, and classic survey sampling strategies based on random sampling therefore require increasingly large sample sizes. More efficient strategies for survey design and analysis can be obtained by exploiting any spatial correlation in prevalence within a model-based geostatistics framework. This framework can be used for constructing predictive probability maps that can inform in-country decision makers of the likelihood that their elimination target has been met, and where to invest in additional sampling. We evaluated our methodology using a case study of lymphatic filariasis in Ghana, demonstrating that a geostatistical approach outperforms approaches currently used to determine an evaluation unit’s elimination status.

Potential factors influencing lymphatic filariasis transmission in \u201chotspot\u201d and \u201ccontrol\u201d areas in Ghana: the importance of vectors

BackgroundMass drug administration (MDA) programmes for the control of lymphatic filariasis in Ghana, have been ongoing in some endemic districts for 16 years. The current study aimed to assess factors that govern the success of MDA programmes for breaking transmission of lymphatic filariasis in Ghana.MethodsThe study was undertaken in two “hotspot” districts (Ahanta West and Kassena Nankana West) and two control districts (Mpohor and Bongo) in Ghana. Mosquitoes were collected and identified using morphological and molecular tools. A proportion of the cibarial armatures of each species was examined. Dissections were performed on Anopheles gambiae for filarial worm detection. A questionnaire was administered to obtain information on MDA compliance and vector control activities. Data were compared between districts to determine factors that might explain persistent transmission of lymphatic filariasis.ResultsHigh numbers of mosquitoes were sampled in Ahanta West district compared to Mpohor district (F = 16.09, P = 0.002). There was no significant difference between the numbers of mosquitoes collected in Kassena Nankana West and Bongo districts (F = 2.16, P = 0.185). Mansonia species were predominant in Ahanta West district. An. coluzzii mosquitoes were prevalent in all districts. An. melas with infected and infective filarial worms was found only in Ahanta West district. No differences were found in cibarial teeth numbers and shape for mosquito species in the surveyed districts. Reported MDA coverage was high in all districts. The average use of bednet and indoor residual spraying was 82.4 and 66.2%, respectively. There was high compliance in the five preceding MDA rounds in Ahanta West and Kassena Nankana West districts, both considered hotspots of lymphatic filariasis transmission.ConclusionsThe study on persistent transmission of lymphatic filariasis in the two areas in Ghana present information that shows the importance of local understanding of factors affecting control and elimination of lymphatic filariasis. Unlike Kassena Nankana West district where transmission dynamics could be explained by initial infection prevalence and low vector densities, ongoing lymphatic filariasis transmission in Ahanta West district might be explained by high biting rates of An. gambiae and initial infection prevalence, coupled with high densities of An. melas and Mansonia vector species that have low or no teeth and exhibiting limitation.

An assessment of mosquito collection techniques for xenomonitoring of anopheline-transmitted Lymphatic Filariasis in Ghana.

Monitoring vectors is relevant to ascertain transmission of lymphatic filariasis (LF). This may require the best sampling method that can capture high numbers of specific species to give indication of transmission. Gravid anophelines are good indicators for assessing transmission due to close contact with humans through blood meals. This study compared the efficiency of an Anopheles gravid trap (AGT) with other mosquito collection methods including the box and the Centres for Disease Control and Prevention gravid, light, exit and BioGent-sentinel traps, indoor resting collection (IRC) and pyrethrum spray catches across two endemic regions of Ghana. The AGT showed high trapping efficiency by collecting the highest mean number of anophelines per night in the Western (4.6) and Northern (7.3) regions compared with the outdoor collection methods. Additionally, IRC was similarly efficient in the Northern region (8.9) where vectors exhibit a high degree of endophily. AGT also showed good trapping potential for collecting Anopheles melas which is usually difficult to catch with existing methods. Screening of mosquitoes for infection showed a 0.80-3.01% Wuchereria bancrofti and 2.15-3.27% Plasmodium spp. in Anopheles gambiae. The AGT has shown to be appropriate for surveying Anopheles populations and can be useful for xenomonitoring for both LF and malaria.

Community-based trial of annual versus biannual single-dose ivermectin plus albendazole against Wuchereria bancrofti infection in human and mosquito populations: study protocol for a cluster randomised controlled trial

BackgroundThe Global Programme for the Elimination of Lymphatic Filariasis (GPELF) has been in operation since the year 2000, with the aim of eliminating the disease by the year 2020, following five to six rounds of effective annual mass drug administration (MDA). The treatment regimen is ivermectin (IVM) in combination with diethylcarbamazine (DEC) or albendazole (ALB). In Ghana, MDA has been undertaken since 2001. While the disease has been eliminated in many areas, transmission has persisted in some implementation units that had experienced 15 or more rounds of MDA. Thus, new intervention strategies could eliminate residual infection in areas of persistent transmission and speed up the lymphatic filariasis (LF)-elimination process. This study, therefore, seeks to test the hypothesis that biannual treatment of LF-endemic communities will accelerate the interruption of LF in areas of persistent transmission.MethodsA cluster randomised trial will be implemented in LF-endemic communities in Ghana. The interventions will be yearly or twice-yearly MDA delivered to entire endemic communities. Allocation to study group will be by clusters identified using the prevalence of LF. Clusters will be randomised to one of two groups: receiving either (1) annual treatment with IVM + ALB or (2) annual MDA with IVM + ALB, followed by an additional MDA 6 months later. The primary outcome measure is the prevalence of LF infection, assessed by four cross-sectional surveys. Entomological assessments will also be undertaken to evaluate the transmission intensity of the disease in the study clusters. Costs and cost-effectiveness will be evaluated. Among a random subsample of participants, microfilaria prevalence will be assessed longitudinally. A nested process evaluation, using semi-structured interviews, focus group discussions and a stakeholder analysis, will investigate the community acceptability, feasibility and scale-up of each delivery system.DiscussionIt is expected that this study will add to the existing evidence on the need for alternative intervention strategies for the elimination of LF in Ghana and in other African countries that are facing similar challenges or are at the beginning of their LF-elimination programmes.Trial registrationClinicalTrials.gov, ID: NCT03036059. Registered on 26 January 2017.Pan African Clinical Trials Registry, ID: PACTR201702002012425. Registered on 23 February 2017.

Fifteen years of programme implementation for the elimination of Lymphatic Filariasis in Ghana: Impact of MDA on immunoparasitological indicators.

Fifteen years of programme implementation for the elimination of Lymphatic Filariasis in Ghana: Impact of MDA on immunoparasitological indicators.

Evaluation of human and mosquito based diagnostic tools for defining endpoints for elimination of Anopheles transmitted lymphatic filariasis in Ghana.

The decision to stop mass drug administration (MDA) and monitor recrudescence has to be made when endpoints for elimination of lymphatic filariasis (LF) have been achieved. Highly sensitive and specific diagnostic tools are required to do this. The main objective of this study was to determine most effective diagnostic tools for assessing interruption of LF transmission. The presence of filarial infection in blood and mosquito samples was determined using five diagnostic tools: Brugia malayi-14 (BM14) antibody detection ELISA, Onchocerca gibsoni antigen (Og4C3) based ELISA, PCR, immunochromatography (ICT) card test and blood smear. The study was carried out in two communities in the Central Region of Ghana. OG4C3 was found to be the most sensitive test but ICT, the second most sensitive, was the most field applicable. PCR was found to be the most specific. Thirteen out of 30 pools of anopheles mosquitoes tested positive for the DNA of Wuchereria bancrofti. Very low antigen prevalence in primary school children indicates that MDA is working, so children born since the intervention was put in place are not getting infected. Inclusion of xenomonitoring in monitoring the effectiveness of MDA will give a better indication as to when transmission has been interrupted especially in areas where microfilaria prevalence is lower than 1%.

Mansonia africana and Mansonia uniformis are vectors in the transmission of Wuchereria bancrofti lymphatic filariasis in Ghana.

BackgroundRecent data from Ghana indicates that after seven rounds of annual mass drug administration (MDA) there is still sustained transmission albeit at low levels in certain areas where Anopheles melas, An. gambiae s.s., Mansonia and Culex species are the main biting mosquitoes. Anopheles gambiae s.l. and An. funestus are the known vectors in Ghana and a recent report indicated that An. melas could transmit at low level microfilaraemia. However, because An. melas is not found everywhere there was the need to determine whether any of the other culicine species could also be playing a role in the transmission of LF.MethodsIndoor mosquitoes collected once a month for three months using pyrethrum spray catches in six communities within the Kommenda-Edina-Eguafo-Abirem (KEEA) District, Central Region of Ghana were morphologically identified, dissected and examined for the presence of W. bancrofti. Additionally, stored mosquito samples collected during previous years in 8 communities from the Gomoa District also in the Central Region were similarly processed. The identities of all W. bancrofti parasites found were confirmed using an established PCR method.ResultsA total of 825 indoor resting mosquitoes comprising of 501 Anopheles species, 239 Mansonia species, 84 Culex species and 1 Aedes species were dissected and examined for the presence of W. bancrofti. Mansonia africana had infection and infectivity rates of 2.5%. and 2.1% respectively. Anopheles gambiae s.l. had an infection rate of 0.4% and a similar infectivity rate. None of the Culex sp. and Aedes sp were found with infection. From the stored mosquitoes the infection and infectivity rates for M. africana were 7.6% (N = 144) and 2.8% respectively whilst the corresponding rates for M. uniformis were 2.9% (N = 244) and 0.8%.ConclusionsThis is the first report of Mansonia species as vectors of lymphatic filariasis (LF) in Ghana and in West Africa since that of 1958 in Guinea. The revelation of a hitherto unrecognised vector which is possibly more efficient in transmission than the recognised ones has a profound implication for elimination of lymphatic filariasis programmes in the sub-region.

The role of ultrasonography in the differentiation of the various types of filaricele due to bancroftian filariasis

Objective(i) To determine the frequencies of urogenital pathologies in men infected with bancroftian filariasis, and (ii) to evaluate the role of ultrasonography (USG) as a diagnostic tool to differentiate between diverse pathologies with different clinical implications. To date, all types of scrotal enlargement resulting from lymphatic filariasis (LF) have been summarized under one term: “filaricele”. Patients and methodsData were compiled from recruitment phases for field trials in an endemic area for LF in Ghana. 1453 men aged 18 years and above underwent ultrasound examinations of the scrotum. Observation parameters were: Filaria Dance Sign (FDS), dilation of supratesticular lymphatic vessels, thickness of scrotal skin, occurrence and amount of fluid accumulation, echogenicity of the fluid between the layers of the tunica vaginalis, as well as position and homogenicity of testis, epididymis and spermatic cord. In 1132 men, blood samples were taken for parasitological analysis. ResultsIn 56% of examined patients, fluid accumulation around the testis was detected (38% subclinical-, 18% clinical stages). Differentiation of the echogenicity of the fluid revealed echo-free hydrocele (EFH) in 47% and echo-dense hydrocele (EDH) in 9%. Patients without hydrocele and subclinical stages had a thinner scrotal skin than those in clinical stages or with lymphscrotum (P<0.001). In the EDH group the scrotal skin was thicker than in the EFH group (P<0.001). 1.4% had a lymphscrotum. FDS was detected in 24% of all 1453 volunteers who underwent USG. The number of worm nests correlated with microfilarial load and levels of circulating filarial antigen (P<0.001; 20% microfilaremic, 48% antigen positive). ConclusionIn an unexpected high number of men (56%) fluid accumulation around the testis was detected by USG of which more than one third (38%) presented with subclinical stages. The study showed that echo-dense and echo-free fluid could be differentiated and that a considerable number of cases had EDH (9%) posing a risk to develop necrotic testis and infertility and therefore requiring immediate surgical intervention.USG thus turned out to be a useful diagnostic technique to differentiate between those cases requiring immediate surgical intervention from those that can be treated with (anti-wolbachial and hyperpermeability reducing) drugs that ameliorate or halt progression of the disease.

Lymphatic filariasis in Ghana: establishing the potential for an urban cycle of transmission

Lymphatic filariasis is a significant public health and economic problem in many tropical and sub-tropical regions. Unplanned urbanization leading to a lack of proper sanitary conditions has resulted in an increase in the urban-based transmission of a number of vector-borne diseases, including lymphatic filariasis. It has been well established that lymphatic filariasis is endemic in rural areas of Ghana. The goal of this study was to determine if there is a potential of establishing urban transmission cycles in Ghana's major cities. We clinically and immunologically assessed 625 individuals from the three major urban areas (Bawku, Bolgatanga and Secondi/Takoradi), finding that the prevalence of infection with Wuchereria bancrofti ranged from 0 to 12.5%. The results of a polymerase chain reaction based analysis of mosquitoes collected from these areas suggested that there is a low but detectable prevalence of mosquitoes infected with W. bancrofti. We conclude that there may be a potential for an established urban transmission of lymphatic filariasis in Ghana.

Ivermectin and albendazole alone and in combination for the treatment of lymphatic filariasis in Ghana: follow-up after re-treatment with the combination

The efficacy of re-treatment with the combination of ivermectin (150–200 μg/kg bodyweight) and albendazole (400 mg) on Wuchereria bancrofti microfilaraemia was assessed in 1997–1999 in 4 groups of individuals from coastal Ghana, which 1 year previously had received a primary treatment with placebo ( n = 38), albendazole ( n = 39), ivermectin ( n = 34) or combination of albendazole and ivermectin ( n = 42), respectively. One year after the re-treatment, an overall mean reduction in microfilarial intensity of 76·2% in relation to the intensity before re-treatment was observed, with no statistical significant difference between the 4 groups. The groups given primary treatment with placebo or the drug combination showed re-treatment reductions which were lower (72·5% and 69·8%, respectively) but not statistically significantly different from the reduction observed 1 year after the primary treatment with the combination (86·7%). The efficacy of the combination treatment thus appeared to be largely independent of the type of primary treatment given and multiplicative when used repeatedly.

Lymphatic filariasis in Ghana: entomological investigation of transmission dynamics and intensity in communities served by irrigation systems in the Upper East Region of Ghana.

We conducted an entomological study to document the effect of irrigation on the vectors and transmission dynamics of lymphatic filariasis in the Upper East Region of Ghana. Mosquitoes were collected by indoor spraying of houses in a cluster of communities located around irrigation projects (Tono and Vea) and others without reservoirs (Azoka). Anopheles gambiae s.s. was the dominant species and major vector, followed by An. funestus. Anopheles arabiensis constituted 9--14% of the An. gambiae complex but none were infective. Culex quinquefasciatus was also not infective in these communities. Chromosomal examinations showed that >60% (n=280--386) of the An. gambiae s.s. in irrigated communities were Mopti forms whilst 73% (n=224) in the non-irrigated area were Savannah forms. Infectivity rates (2.3--2.8 vs. 0.25), worm load (1.62--2.04 vs. 1.0), annual bites per person (6.50--8.83 vs. 0.47) and annual transmission potential (13.26--14.30 vs. 0.47) were significantly higher in irrigated communities.

Lymphatic filariasis in Ghana: from research to control

Lymphatic filariasis in Ghana: from research to control

A randomized double-blind placebo-controlled field trial of ivermectin and albendazole alone and in combination for the treatment of lymphatic filariasis in Ghana

The efficacy and safety of single-dose ivermectin (150–200 μg/kg) and albendazole (400 mg) treatment administered separately or in combination for Wuchereria bancrofti infections were assessed in 1996–1998 in a randomized double-blind placebo-controlled field trial in Ghana: 1425 individuals from 4 lymphatic filariasis-endemic villages, 340 of whom were microfilaria (mf)-positive before treatment, were randomized into 4 groups to receive albendazole alone, ivermectin alone, combination of albendazole and ivermectin, or placebo, respectively. Individuals were followed for 5 days after treatment to record any adverse reactions, and the effect of treatment on microfilaraemia was monitored in night-blood samples after 3, 6 and 12 months. Treatment efficacy was analysed for 236 mf-positive individuals who had ⩾100 mf/mL of blood and who were also present for examination at 12 months after treatment. Compared to the placebo group, the ivermectin and combination groups both showed statistically significant reductions in geometric mean mf intensities at the follow-up examinations (to 6·7% and 0·9%, 9·9% and 6·9%, and 21·7% and 11·4% of pre-treatment levels, respectively, at 3, 6 and 12 months after treatment). Compared to the ivermectin group, however, the reduction in the combination group was significantly greater only at 3 months after treatment, but not after 6 or 12 months. The albendazole group showed a slow but non-significant reduction over the same period. Adverse reactions were few and mostly mild (no severe reactions were recorded), and no significant differences were observed between the treatment groups. Both ivermectin and combination treatment thus appeared effective and safe for treatment of lymphatic filariasis, but the difference in efficacy was minor and the study did not provide clear evidence for the combination drug therapy, as compared to ivermectin therapy alone, to be superior for control of lymphatic filariasis.

Rapid community diagnosis of lymphatic filariasis

We conducted a pilot study to test rapid assessment procedures for the community diagnosis of lymphatic filariasis in some rural communities in Ghana. The assessment criteria included direct key informant interviews, focus group discussions, routine reporting from health facilities, self-administered questionnaires, and a random examination of adult males for hydroceles. All the data collection methods were easy, convenient, non-invasive to use and acceptable to the community. The study provided reliable estimates of the burden of lymphatic filariasis in the community when compared with data from standard epidemiological surveys. The direct key informant interviews and focus group discussions gave a broad perspective of the burden of diseases in the community in general, and lymphatic filariasis in particular. The use of self-administered questionnaires provided data comparable with data on elephantiasis in the community from a case search. Examination of a random 30–40 adult males for hydroceles provided a good correlation with the community microfilaria prevalence, with a correlation coefficient of linear regression r=0.79. These individual rapid assessment procedures of the burden of lymphatic filariasis, if further developed and tested could, be widely used in combination for the mapping of the distribution of lymphatic filariasis in Ghana and possibly, the African sub-region.

Descriptive epidemiology of lymphatic filariasis in Ghana

A national filariasis survey was conducted to determine the prevalence and distribution of Wuchereria bancrofti microfilaraemia and clinical disease associated with lymphatic filariasis in Ghana. Multi-stage systematic sampling was used to select households to be examined in all 10 administrative regions of the country. The results showed a high prevalence of microfilaraemia and disease with considerable regional variation in all the quantities investigated. In general, the disease was more prevalent in the northern guinea savannah and the southern coastal savannah, while the middle forest belt was relatively free. Even within the regions, there was considerable variation in the distribution of the disease. The disease is of potentially major public health significance, particularly in the northern and coastal savannahs, and requires the design and implementation of a control programme.