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Background The Global Programme to Eliminate Lymphatic Filariasis (GPELF) aims to reduce and maintain infection levels through mass drug administration (MDA), but there is evidence of ongoing transmission after MDA in areas where Culex mosquitoes are the main transmission vector, suggesting that a more stringent criterion is required for MDA decision making in these settings. Methods We use a transmission model to investigate how a lower prevalence threshold (<1% antigenemia [Ag] prevalence compared with <2% Ag prevalence) for MDA decision making would affect the probability of local elimination, health outcomes, the number of MDA rounds, including restarts, and program costs associated with MDA and surveys across different scenarios. To determine the cost-effectiveness of switching to a lower threshold, we simulated 65% and 80% MDA coverage of the total population for different willingness to pay per disability-adjusted life-year averted for India ($446.07), Tanzania ($389.83), and Haiti ($219.84). Results Our results suggest that with a lower Ag threshold, there is a small proportion of simulations where extra rounds are required to reach the target, but this also reduces the need to restart MDA later in the program. For 80% coverage, the lower threshold is cost-effective across all baseline prevalences for India, Tanzania, and Haiti. For 65% MDA coverage, the lower threshold is not cost-effective due to additional MDA rounds, although it increases the probability of local elimination. Valuing the benefits of elimination to align with the GPELF goals, we find that a willingness to pay per capita government expenditure of approximately $1000–$4000 for 1% increase in the probability of local elimination would be required to make a lower threshold cost-effective. Conclusions Lower Ag thresholds for stopping MDAs generally mean a higher probability of local elimination, reducing long-term costs and health impacts. However, they may also lead to an increased number of MDA rounds required to reach the lower threshold and, therefore, increased short-term costs. Collectively, our analyses highlight that lower target Ag thresholds have the potential to assist programs in achieving lymphatic filariasis goals. [ABSTRACT FROM AUTHOR]

Background Mass drug administration (MDA) is the cornerstone for the elimination of lymphatic filariasis (LF). The proportion of the population that is never treated (NT) is a crucial determinant of whether this goal is achieved within reasonable time frames. Methods Using 2 individual-based stochastic LF transmission models, we assess the maximum permissible level of NT for which the 1% microfilaremia (mf) prevalence threshold can be achieved (with 90% probability) within 10 years under different scenarios of annual MDA coverage, drug combination and transmission setting. Results For Anopheles -transmission settings, we find that treating 80% of the eligible population annually with ivermectin + albendazole (IA) can achieve the 1% mf prevalence threshold within 10 years of annual treatment when baseline mf prevalence is 10%, as long as NT <10%. Higher proportions of NT are acceptable when more efficacious treatment regimens are used. For Culex -transmission settings with a low (5%) baseline mf prevalence and diethylcarbamazine + albendazole (DA) or ivermectin + diethylcarbamazine + albendazole (IDA) treatment, elimination can be reached if treatment coverage among eligibles is 80% or higher. For 10% baseline mf prevalence, the target can be achieved when the annual coverage is 80% and NT ≤15%. Higher infection prevalence or levels of NT would make achieving the target more difficult. Conclusions The proportion of people never treated in MDA programmes for LF can strongly influence the achievement of elimination and the impact of NT is greater in high transmission areas. This study provides a starting point for further development of criteria for the evaluation of NT. [ABSTRACT FROM AUTHOR]

Mass drug administration (MDA) of antifilarial drugs is the main strategy for the elimination of lymphatic filariasis (LF). Recent clinical trials indicated that the triple-drug therapy with ivermectin, diethylcarbamazine, and albendazole (IDA) is much more effective against LF than the widely used two-drug combinations (albendazole plus either ivermectin or diethylcarbamazine). For IDA-based MDA, the stop-MDA decision is made based on microfilariae (mf) prevalence in adults. In this study, we assess how the probability of eventually reaching elimination of transmission depends on the critical threshold used in transmission assessment surveys (TAS-es) to define whether transmission was successfully suppressed and triple-drug MDA can be stopped. This analysis focuses on treatment-naive Indian settings. We do this for a range of epidemiological and programmatic contexts, using the established LYMFASIM model for transmission and control of LF. Based on our simulations, a single TAS, one year after the last MDA round, provides limited predictive value of having achieved suppressed transmission, while a higher MDA coverage increases elimination probability, thus leading to a higher predictive value. Every additional TAS, conditional on previous TAS-es being passed with the same threshold, further improves the predictive value for low values of stop-MDA thresholds. An mf prevalence threshold of 0.5% corresponding to TAS-3 results in ≥95% predictive value even when the MDA coverage is relatively low. [ABSTRACT FROM AUTHOR]

The Global Programme to Eliminate Lymphatic Filariasis (GPELF) was established with the ambitious goal of eliminating LF as a public health problem. The remarkable success of the GPELF over the past 2 decades in carrying out its principal strategy of scaling up and scaling down mass drug administration has relied first on the development of a rigorous monitoring and evaluation (M&E) framework and then the willingness of the World Health Organization and its community of partners to modify this framework in response to the practical experiences of national programmes. This flexibility was facilitated by the strong partnership that developed among researchers, LF programme managers and donors willing to support the necessary research agenda. This brief review summarizes the historical evolution of the GPELF M&E strategies and highlights current research needed to achieve the elimination goal. [ABSTRACT FROM AUTHOR]

The Global Programme to Eliminate Lymphatic Filariasis (LF) is using mass drug administration (MDA) of antifilarial medications to treat filarial infections, prevent disease and interrupt transmission. Almost 500 million people receive these medications each year. Clinical trials have recently shown that a single dose of a triple-drug combination comprised of ivermectin, diethylcarbamazine and albendazole (IDA) is dramatically superior to widely used two-drug combinations for clearing larval filarial parasites from the blood of infected persons. A large multicenter community study showed that IDA was well-tolerated when it was provided as MDA. IDA was rapidly advanced from clinical trial to policy and implementation; it has the potential to accelerate LF elimination in many endemic countries. [ABSTRACT FROM AUTHOR]

Lymphatic filariasis (LF) and soil-transmitted-helminths (STH) are co-endemic in 58 countries which are mostly in Africa and Asia. Worldwide, 486 million school-age children are considered at risk of both diseases. In 2000, the World Health Organization (WHO) established the global programme to eliminate LF by 2020. Since then, the LF elimination programme has distributed ivermectin or diethylcarbamazine citrate (DEC) in combination with albendazole, thereby also treating STH. Consequently, many school-age children have been treated for STH through the LF programme. As treatment targets towards the 2020 LF elimination goal are achieved, many countries are implementing the transmission assessment survey (TAS) and, if the LF prevalence is estimated to be less than 1%, scaling down mass drug administration (MDA). We analysed the 2014 data on preventive chemotherapy (PC) reported from LF STH co-endemic countries and projected the year and location of TAS expected to be conducted between 2016 and 2020 to assess the impact of this scaling down on STH PC. Eighty percent of all co-endemic countries that have already stopped LF MDA nationally were able to establish STH PC through schools. It is estimated that 14% of the total number of children presently covered by the LF programme is at risk of not continuing to receive PC for STH. In order to achieve and maintain the WHO 2020 goal for STH control, there is an urgent need to establish and reinforce school-based deworming programmes in countries scaling-down national LF elimination programmes. [ABSTRACT FROM AUTHOR]

The article discusses the Global Programme to Eliminate Lymphatic Filariasis (LF), a disease caused by filarial worms that affects over 1.39 billion people in 73 countries. The program aims to eliminate LF as a public health problem by 2020 through mass drug administration (MDA) and post-MDA surveillance. The World Health Organization's Global Programme to Eliminate Lymphatic Filariasis (GPELF) plays a crucial role in coordinating efforts and collaborating with other neglected tropical disease programs. The program is monitored by independent review groups and reports progress to the World Health Organization. [Extracted from the article]

Background: To eliminate blinding trachoma, the World Health Organization emphasizes implementing the SAFE strategy, which includes annual mass drug administration (MDA) with azithromycin to the whole population of endemic districts. Prevalence surveys to assess impact at the district level are recommended after at least 3 years of intervention. The decision to stop MDA is based on a prevalence of trachomatous inflammation follicular (TF) among children aged 1–9 years below 5% at the sub-district level, as determined by an additional round of surveys limited within districts where TF prevalence is below 10%. We conducted impact surveys powered to estimate prevalence simultaneously at the sub-district and district in two zones of Amhara, Ethiopia to determine whether MDA could be stopped. Methodology: Seventy-two separate population-based, sub-district surveys were conducted in 25 districts. In each survey all residents from 10 randomly selected clusters were screened for clinical signs of trachoma. Data were weighted according to selection probabilities and adjusted for correlation due to clustering. Principal Findings: Overall, 89,735 residents were registered from 21,327 households of whom 72,452 people (80.7%) were examined. The prevalence of TF in children aged 1–9 years was below 5% in six sub-districts and two districts. Sub-district level prevalence of TF in children aged 1–9 years ranged from 0.9–76.9% and district-level from 0.9–67.0%. In only one district was the prevalence of trichiasis below 0.1%. Conclusions/Significance: The experience from these zones in Ethiopia demonstrates that impact assessments designed to give a prevalence estimate of TF at sub-district level are possible, although the scale of the work was challenging. Given the assessed district-level prevalence of TF, sub-district-level surveys would have been warranted in only five districts. Interpretation was not as simple as stopping MDA in sub-districts below 5% given programmatic challenges of exempting sub-districts from a highly regarded program and the proximity of hyper-endemic sub-districts. Author Summary: Trachoma, the leading cause of preventable blindness, is targeted for "elimination as a public health problem" by the year 2020. National programs are implementing the recommended strategy of surgery, antibiotics, facial cleanliness, and environmental improvements (SAFE) to meet this target. Many programs are currently facing the decision of when to scale down interventions, particularly mass drug administration (MDA) of azithromycin. We implemented large population-based surveys in two different zones of the Amhara National Regional State of Ethiopia. Rather than conducting an impact assessment first at the district level, followed by additional sub-district-level surveys, we took a novel approach to measure the prevalence of trachoma at sub-district level to be able to make an immediate decision of whether to stop MDA. Over 72,000 people in 714 communities in 72 sub-districts were examined for clinical signs of trachoma. We identified only six sub-districts that met criteria for being able to stop MDA. Our work demonstrates that determining the prevalence of trachoma at sub-district level is feasible but requires significant resources. In this hyper-endemic setting, sub-district-level surveys were not needed in the majority of districts. Overall, the clinical data suggest some decline in trachoma within these areas since the SAFE strategy was implemented. [ABSTRACT FROM AUTHOR]

Mass drug administration (MDA) with antibiotics is a key component of the SAFE strategy for trachoma control. Guidelines recommend that where MDA is warranted the whole population be targeted with 80% considered the minimum acceptable coverage. In other countries, MDA is usually conducted by salaried Ministry of Health personnel (MOH). In Plateau State, Nigeria, the existing network of volunteer Community Directed Distributors (CDD) was used for the first trachoma MDA. We conducted a population-based cluster random survey (CRS) of MDA participation to determine the true coverage and compared this to coverage reported from CDD registers. We surveyed 1,791 people from 352 randomly selected households in 24 clusters in three districts in Plateau State in January 2011, following the implementation of MDA. Households were enumerated and all individuals present were asked about MDA participation. Household heads were questioned about household-level characteristics and predictors of participation. Individual responses were compared with the CDD registers. MDA coverage was estimated as 60.3% (95% CI 47.9–73.8%) by the survey compared with 75.8% from administrative program reports. CDD registration books for comparison with responses were available in 19 of the 24 clusters; there was a match for 658/682 (96%) of verifiable responses. CDD registers did not list 481 (41.3%) of the individuals surveyed. Gender and age were not associated with individual participation. Overall MDA coverage was lower than the minimum 80% target. The observed discrepancy between the administrative coverage estimate from program reports and the CRS was largely due to identification of communities missed by the MDA and not reported in the registers. CRS for evaluation of MDA provides a useful additional monitoring tool to CDD registers. These data support modification of distributor training and MDA delivery to increase coverage in subsequent rounds of MDA. Author Summary: The World Health Organization recommends that mass drug administration for trachoma control reach a minimum of 80% of the target population. Previous evaluations of MDA coverage have demonstrated that administrative reports can bias coverage estimates. A survey of participation in mass drug administration for trachoma control was implemented in three districts in Plateau State, Nigeria in 2011 to validate coverage calculated from treatment registers. A total of 352 households were surveyed from 24 randomly selected communities. Heads of household were interviewed to identify household-level characteristics and predictors of participation. Individual household members were enumerated and those present at the time of interview were asked to report individual participation in the MDA. Responses were verified against the community-drug distributor registration log. Approximately 60% of the sample reported receiving either tetracycline eye ointment or azithromycin for trachoma control. Administrative data on treatment estimated coverage at 76% for the three LGAs. The discrepancy between the coverage estimate from administrative data (calculated by the program) and the survey data suggest that cluster random surveys of MDA provide a useful monitoring tool to validate administrative data on treatment coverage. These data support modification of distributor training and MDA delivery to increase coverage in subsequent rounds of MDA. [ABSTRACT FROM AUTHOR]

Abstract: In the context of trachoma control, population coverage with mass drug administration (MDA) using antibiotics is measured using routine data. Due to the limitations of administrative records as well as the potential for bias from incomplete or incorrect records, a literature review of coverage survey methods applied in neglected tropical disease control programmes and immunisation outreach was conducted to inform the design of coverage surveys for trachoma control. Several methods were identified, including the ‘30 × 7’ survey method for the Expanded Programme on Immunization (EPI 30×7), other cluster random sampling (CRS) methods, lot quality assurance sampling (LQAS), purposive sampling and routine data. When compared against one another, the EPI and other CRS methods produced similar population coverage estimates, whilst LQAS, purposive sampling and use of administrative data did not generate estimates consistent with CRS. In conclusion, CRS methods present a consistent approach for MDA coverage surveys despite different methods of household selection. They merit use until standard guidelines are available. CRS methods should be used to verify population coverage derived from LQAS, purposive sampling methods and administrative reports. [ABSTRACT FROM AUTHOR]

Objectives: A national survey in 1997 demonstrated that trachoma was endemic in Mali. Interventions to control trachoma including mass drug administration (MDA) with azithromycin were launched in the regions of Kayes and Koulikoro in 2003. MDA was discontinued after three annual rounds in 2006, and an impact survey conducted. We resurveyed all districts in Kayes and Koulikoro in 2009 to reassess trachoma prevalence and determine intervention objectives for the future. In this paper we present findings from both the 2006 and 2009 surveys. Methods: Population-based cluster surveys were conducted in each of the nine districts in Koulikoro in 2006 and 2009, whilst in Kayes, four of seven districts in 2006 and all seven districts in 2009 were surveyed. Household members present were examined for clinical signs of trachoma. Results: Overall, 29,179 persons from 2,528 compounds, in 260 clusters were examined in 2006 and 32,918 from 7,533 households in 320 clusters in 2009. The prevalence of TF in children aged 1-9 years in Kayes and Koulikoro was 3.9% (95%CI 2.9-5.0%, range by district 1.2-5.4%) and 2.7% (95%CI 2.3-3.1%, range by district 0.1-5.0%) respectively in 2006. In 2009 TF prevalence was 7.26% (95%CI 6.2-8.2%, range by district 2.5-15.4%) in Kayes and 8.19% (95%CI 7.3-9.1%, range by district 1.7-17.2%) in Koulikoro among children of the same age group. TT in adults 15 years of age and older was 2.37% (95%CI 1.66-3.07%, range by district 0.30-3.54%) in 2006 and 1.37% (95%CI 1.02-1.72%, range by district 0.37-1.87%) in 2009 in Kayes and 1.75% (95%CI 1.31-2.23%, range by district 1.06-2.49%) in 2006 and 1.08% (95%CI 0.86-1.30%, range by district 0.34-1.78%) in 2009 in Koulikoro. Conclusions: Using WHO guidelines for decision making, four districts, Bafoulabe in Kayes Region; and Banamba, Kolokani and Koulikoro in Koulikoro Region, still meet criteria for district-wide implementation of the full SAFE strategy as TF in children exceeds 10%. A community-by-community approach to trachoma control may now be required in the other twelve districts. Trichiasis surgery provision remains a need in all districts and should be enhanced in six districts in Kayes and five in Koulikoro where the prevalence exceeded 1.0% in adults. Since 1997 great progress has been observed in the fight against blinding trachoma; however, greater effort is required to meet the elimination target of 2015. [ABSTRACT FROM AUTHOR]

Summary: Trachoma control includes mass drug administration (MDA) with antibiotics targeting coverage of at least 80%. Coverage is traditionally calculated by dividing doses distributed by population estimate, which is unreliable. We compared a verifiable coverage assessment method against self-reported participation and the traditional calculation, and examined factors associated with MDA participation in Akobo County, Southern Sudan. During MDA, recipients were marked with indelible ink and followed-up using a two-stage household survey: 25 clusters from three districts, and 10 households per cluster. All household members were enumerated; asked about self-reported participation and observed for indelible marks. Household heads were interviewed to assess factors associated with MDA. Overall 11 419 treatments were given and 1358 residents from 247 households surveyed. By traditional methods MDA coverage was 20.9% (95% CI: 20.6-21.3); 61.5% (95 % CI: 49.4-73.6) by self-reporting; and 37.5% (95% CI: 25.1%-49.9%) from observed ink marks. Controlling for other factors, presence of a health worker (OR 2.3, 95% CI: 1.5-3.6); head of household knowledge of azithromycin (OR 1.6, 95% CI: 1.5-3.1); and head of household advance notice of MDA (OR 34.9, 18.1-66.3) were independent predictors of participation. Cluster randomised surveys can estimate MDA coverage better than the traditional method and implementation of indelible marking merits investigation. [Copyright &y& Elsevier]

Study objectives: This article presents findings from a rapid review of qualitative research conducted to inform decision makers about community and drug distributor perceptions and experiences of mass drug administration campaigns for the elimination of lymphatic filariasis. We focused on questions related to acceptability of the mass drug administration campaigns within these groups and their thoughts around the feasibility of planning and carrying out the campaigns. Methods: We carried out a systematic search in five databases to identify potential studies. We included studies that focused on community members and drug distributors and used qualitative methods for data collection and analysis. We conducted a thematic framework analysis using the Supporting the Use of Research Evidence framework. Due to time constraints, one author conducted the screening, extraction and data analysis. Findings: Studies found that communities lack knowledge and information about lymphatic filariasis and the mass drug administration campaigns and that this can have an impact on how many community members choose to take medication. Health workers often had a good understanding that lymphatic filariasis was a problem in their setting, of its cause and mode of transmission and that hydrocele and elephantiasis had the same cause. However, this knowledge was not as prevalent amongst community drug distributors who often had misconceptions surrounding the topic. Furthermore, studies found that the length, timing, level of community and health system involvement, access to care for side effects, inadequate numbers of drug distributors and supervisors and motivation of drug distributors influenced participation in mass drug administration campaigns. Finally, the inadequate training of drug distributors could influence community trust in the mass drug administration program and the drug distributor themselves if there was a perception that the person was uninformed or not trained to carry out their tasks. [ABSTRACT FROM AUTHOR]

Objective--To establish pharmacokinetics of rebenacexib after administration to cats via the IV, SC, and oral routes. Animals--24 cats. Procedures--In a crossover design, robenacoxib was administered IV, SC, and orally (experiment 1) and orally (experiment 2)to cats with different feeding regimens. Blood robenacoxib concentrations were assayed, with a lower limit of quantification of 3 ng/mL. Results--In experiment 1, geometric mean pharmacokinetic values after IV administration of robenacoxib were as follows: blood clearance, 0.44 L/kg/h; plasma clearance, 0.29 L/kg/h; elimination half-life, 1.49 hours; and volume of distribution at steady state (determined from estimated plasma concentrations), 0.13 L/kg. Mean bioavailability was 69% and median time to maximum concentration (Cmax) was 1 hour for cats after SC administration of robenacoxib, whereas mean bioavailability was 49% and 10% and median time to Cmax was 1 hour and 30 minutes after oral administration to cats after food withholding and after cats were fed their entire ration, respectively. In experiment 2, geometric mean Cmax was 1,159, 1,200, and 692 ng/mL and area under the curve from 0 to infinity was 1,337, 1,383, and 1,069 ng X h/mL following oral administration to cats after food withholding, cats fed one-third of the daily ration, and cats fed the entire daily ration, respectively. Conclusions and Clinical Relevance--For treatment of acute conditions in cats, it is recommended to administer robenacoxib by IV or SC injection, orally after food withholding, or orally with a small amount of food to obtain optimal bioavailability and Cmax. [ABSTRACT FROM AUTHOR]

Abstract: In 2000, the American Samoa Department of Health initiated a campaign of annual mass drug administration (MDA) with albendazole and diethylcarbamazine (DEC) to eliminate transmission of filariasis. Drug coverage was well below prescribed targets in the first three campaigns, ranging from 24 to 52% of the total population. Evaluation findings from a variety of formative research methods identified opportunities to improve MDA coverage and ensuing program modifications resulted in increased drug coverage of 65–71% in the following four annual distributions. Partnering with churches for drug distribution and using multiple media channels for health promotion led to sustained program improvements. With the increased emphasis on the use of mass distribution for delivery of drugs for a number of neglected tropical diseases, other programs may benefit from a similar approach. [Copyright &y& Elsevier]