Epidemiological Coverage Research Articles

Triple-drug therapy with ivermectin, diethylcarbamazine and albendazole for the acceleration of lymphatic filariasis elimination in Kenya: Programmatic implementation and results of the first impact assessment.

The World Health Organization (WHO) endorsed the use of triple-drug mass drug administration (MDA) regimen with ivermectin, diethylcarbamazine (DEC) and albendazole (commonly abbreviated as IDA) to accelerate the elimination of lymphatic filariasis (LF) as a public health problem in settings where onchocerciasis is not co-endemic. The National Programme for Elimination of LF (NPELF) in Kenya was among the first adopters of the IDA-MDA and two annual rounds were provided in 2018 and 2019 to the residents of Lamu County and Jomvu sub-County in the coast region. This study documented the feasibility of successfully delivering the two rounds of IDA-MDA. An operational research study was undertaken to determine efficient sampling strategies, indicators, and the appropriate population groups that could be used for the monitoring and evaluation of LF programs using IDA-MDA for the elimination of the disease as a public health problem. Two cross-sectional surveys were conducted at baseline in 2018 before IDA-MDA and an impact assessment 17 months after the second round of IDA-MDA. The reported epidemiological treatment coverage was at least 80% in all implementation units during each round of IDA-MDA. Blood samples were tested for filarial antigenemia using commercial Filariasis Test Strips (FTS) and any individual found to be positive was tested again at night for the presence of microfilariae in finger prick blood smears using microscopy. The overall prevalence of circulating filarial antigen (CFA) was relatively low at the baseline survey with Jomvu having 1.39% (95% CI: 0.91, 2.11) and Lamu having 0.48% (95% CI: 0.21, 1.13). Significant reduction in CFA prevalence was observed during the impact assessment after the two annual rounds of mass treatment. The overall relative reduction (%) in CFA prevalence following the two rounds of MDA with IDA was significant in both Jomvu (52.45%, Z = -2.46, P < 0.02) and Lamu (52.71%, Z = -1.97, P < 0.05). Heterogeneity, however, was observed in the CFA prevalence reduction between random and purposive clusters, as well as between adult and child populations. The results of the impact assessment survey offered strong evidence that it was safe to stop the IDA-MDA in the two EUs because transmission appears to have been interrupted. It is also important to implement a post-treatment surveillance system which would enable efficient detection of any recrudescence of LF transmission at a sub-evaluation unit level. Our findings show that IDA-MDA may be considered for acceleration of LF elimination in other settings where onchocerciasis is not co-endemic.

The burden of lymphatic filariasis and its control strategies in Sierra Leone: A literature review

Lymphatic filariasis (LF) poses a significant health burden in Sierra Leone, with considerable socio-economic implications. LF, caused by parasitic worms transmitted through mosquito bites, leads to lymphedema, elephantiasis, and hydrocele, severely affecting individuals’ quality of life. Sierra Leone, with its tropical climate and inadequate healthcare infrastructure, faces unique challenges in combating lymphatic filariasis. This review explores the epidemiological landscape of LF in Sierra Leone, highlighting endemic regions, its impact, and control strategies. In 2005, epidemiological coverage of high-dose medications, like ivermectin and albendazole, exceeded 65% annually across 12 districts in Sierra Leone. By 2013, eight districts were eligible for transmission assessment surveys (TAS). After three additional rounds of mass drug administration (MDA), four districts became eligible for pre-TAS assessments in 2017. Despite efforts to control LF through mass drug administration (MDA) programs, challenges such as low treatment coverage, logistical constraints, and community resistance persist. Moreover, the impact of the Ebola outbreak on healthcare delivery has further impeded LF control efforts. This literature review adds to our understanding of LF control in Sierra Leone, providing valuable insights into the epidemiology, impact, challenges, and potential strategies for enhancing LF elimination efforts. It contributes to the broader discourse on neglected tropical diseases and public health interventions, emphasizing the need for context-specific approaches and interdisciplinary collaboration to achieve sustained progress towards LF elimination and improves public health outcomes.

Contextual determinants of mass drug administration performance: Modelling fourteen years of lymphatic filariasis treatments in West Africa.

Effective mass drug administration (MDA) is the cornerstone in the elimination of lymphatic filariasis (LF) and a critical component in combatting all neglected tropical diseases for which preventative chemotherapy is recommended (PC-NTDs). Despite its importance, MDA coverage, however defined, is rarely investigated systematically across time and geography. Most commonly, investigations into coverage react to unsatisfactory outcomes and tend to focus on a single year and health district. Such investigations omit more macro-level influences including sociological, environmental, and programmatic factors. The USAID NTD database contains measures of performance from thousands of district-level LF MDA campaigns across 14 years and 10 West African countries. Specifically, performance was measured as an MDA's epidemiological coverage, calculated as persons treated divided by persons at risk. This analysis aims to explain MDA coverage across time and geography in West Africa using sociological, environmental, and programmatic factors. The analysis links epidemiological coverage data from 3,880 LF MDAs with contextual, non-NTD data via location (each MDA was specific to a health district) and time (MDA month, year). Contextual data included rainfall, temperature, violence or social unrest, COVID-19, the 2014 Ebola outbreak, road access/isolation, population density, observance of Ramadan, and the number of previously completed MDAs. We fit a hierarchical linear regression model with coverage as the dependent variable and performed sensitivity analyses to confirm the selection of the explanatory factors. Above average rainfall, COVID-19, Ebola, violence and social unrest were all significantly associated with lower coverage. Years of prior experience in a district and above average temperature were significantly associated with higher coverage. These generalized and context-focused findings supplement current literature on coverage dynamics and MDA performance. Findings may be used to quantify typically anecdotal considerations in MDA planning. The model and methodology are offered as a tool for further investigation.

Evaluation of therapeutic coverage of mass treatment campaign against lymphatic filariasis in two health districts in Burkina Faso

Burkina Faso has been implementing preventive chemotherapy against lymphatic filariasis since 2001. While 61 health districts (HDs) have stopped mass drug administration (MDA), transmission persists in 9 HDs despite good reported MDA coverage. To validate the reported coverage, an independent post-MDA survey was conducted in Tenkodogo and Fada N'Gourma HDs in September 2018. The study population consisted of all persons in the visited communities. The Coverage survey sample builder (CSSB) tool was used to calculate the sample size and to conduct the random selection of households. A total of 30 villages per HD were selected. The investigators were Ministry of Education agents and health workers not involved in MDA. Data were collected on smartphones through the KoBoCollect application regarding age, sex, drug ingestion (ivermectin + albendazole), adverse events, and whether respondents understood MDA guidelines. Stata Version 14 software was used for data analysis. A total of 3,741 individuals were surveyed, 53.3% were female and the median age was 14 years. Surveyed epidemiological coverage was 74% [95% CI: 72-76.1] in Fada N'Gourma and 79.1% [95% CI: 77.2-80.9] in Tenkodogo, compared to reported coverages of 82.6% and 83% respectively. Village-level coverage ranged from 32.9% to 100% in Fada N'Gourma and from 56.7% to 93.3% in Tenkodogo. In total, 99% of those treated said they had swallowed the drugs in front of the community drug distributor (CDD) and confirmed the use of dose poles. The main reasons for non-treatment were non-visitation of the compound by CDD (54%) and absences during MDA (43%). Results showed that surveyed coverage was lower than reported coverage in both HDs, yet both were above the 65% threshold recommended by WHO. However, major variations of coverage have been noted among villages. Directly observed treatment appeared to have been well respected. The main challenges to increase coverage will be the systematic revisiting of households with absentees and the targeting of all households in each village.

Review on Schistosomiasis: Epidemiology and Clinical Manifestation up to Date

Schistosomiasis is a parasite disease that affects both humans and animals and is brought on by the blood flukes of the genus Schistosoma. It is one of the world’s most enduring neglected tropical diseases. Sub-Saharians make up more than 90% of them, and a significant portion of Ethiopians are afflicted and at risk. It spread across the entire nation and was correlated with the rapid development of water resources and population growth. The two species of freshwater snails, Biomphalaria pfeifferi and Biomphalaria sudanica, are responsible for the parasite’s transmission in Ethiopia. Compared to the three primary schistosomes that infect people, Schistosoma mansoni, Schistosoma haematobium, Schistosoma japonicum, Schistosoma intercalatum, and Schistosoma mekongi have less of an epidemiological impact. Geographically, S. haematobium and S. mansoni are more common in Africa than other species. Epidemiological coverage is also influenced by seasonal distributions throughout the postrainy season, as well as the cold and dry seasons. The organs and systems implicated in its pathogenic dissemination include the intestines, urogenital systems, the pulmonary system, the liver, spleen, and the brain. Ecological change and sociocultural influences are risk factors for water contamination. Regarding clinical symptoms, the penetration of cercariae into the dermis, cercarial dermatitis, acute schistosomiasis, and the chronic stage of infection are significant. Mammals and snails serve as the two hosts for the schistosome life cycle. It can be diagnosed through clinical exams and laboratory techniques. Praziquantel can be used to treat this condition, and it can be prevented by taking precautions during ecological shifts that may result in epidemics. Other measures to take include providing clean water, maintaining good hygiene, controlling mosquitoes, and spreading health awareness.

Pulse-Field Analysis Diversity of Extended Spectrum Beta Lactamases Producing Gram Negative Bacteria Isolated from Periplaneta americana (Cockroaches)

Extended spectrum beta lactamase (ESBL) producing bacteria are organisms of public health significance that have been implicated in prolonged hospital stay, treatment failures and higher fatalities. These organisms were originally thought to be widely distributed in hospital, but have since grown in terms of their epidemiological coverage. This study was therefore aimed at using pulse-field gel electrophoresis (PFGE) to understand the diversity of ESBL producing organisms originating from cockroaches in Ago-Iwoye, Nigeria. The diversity was determined by using a set of twenty six (26) ESBL producing bacterial strains isolated from cockroaches sampled in Ago-Iwoye community, Ogun State, Nigeria. PFGE analysis revealed three pulsotypes (distinct profile) with no distinct isolates present on a pulsotype. It was however observed that no pulsotype had less than two (2) isolates in any case, while isolates from different communities displayed identical profiles. In conclusion, clonal distributions of ESBL producing organisms on cockroaches are without bias to specimens and/or the community sampled.&#x0D; Keywords: ESBL; Gram negative bacteria; PFGE; Diversity;

Global Surveillance Networks and International Health Regulations in the Early Detection and Control of Epidemics

An elaborate global health system has been developed around the world as a bulwark against infectious disease threats. The system consists of various networks of formal and informal organizations serving different stakeholders. This network has different purposes, methods, resources and accountability; it consists of public institutions operating in different fields of influence (at local, national, regional or global level), profit-oriented and non-profit private sector organizations. The current global health system has done important work to protect and improve human health. However, the world continues to face long-standing and emerging or re-emerging infectious disease threats. These threats vary greatly in severity and probability of risk, and each requires separate struggle dynamics. In addition, as with morbidity and mortality rates, these infections have many complex social and economic effects and consequences that differ. It is discussed whether the global health system with its current situation can provide effective protection against a number of communicable disease threats. Due to the recent emerging threats of Ebola, Zika, dengue fever, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), COVID-19, and influenza epidemics, and the increasing threat of antimicrobial resistance, this system is being put to the test. Weak health systems, urbanization, globalization, climate change, civil wars and conflicts, and the changing nature of pathogen transmission between human and animal populations, uncontrolled population growth in some risk areas aggravate current concerns. "Human-induced outbreaks resulting from laboratory accidents" or deliberate biological attacks are considered as other potential risks, making international cooperation and coordination important. International epidemiological surveillance systems and international health regulation coverage are expanding their scope as early intervention practices and tools that are critical in preventing infectious diseases from reaching epidemic levels and minimizing global risks. Also, the effectiveness of early warning surveillance systems is being improved with the use of new technologies.

Implementation of mass drug administration for neglected tropical diseases in Guinea during the COVID-19 pandemic.

Guinea reported its first case of COVID-19 on March 12, 2020. Soon thereafter, a national state of emergency was declared, all land borders were closed, schools were shut down, and public gatherings were limited. Many health activities, including field-based activities targeting neglected tropical diseases (NTDs), were paused. The World Health Organization (WHO) issued updated guidance on the resumption of NTD field-based activities on July 27, 2020. In response, the Guinea Ministry of Health (MoH) and its partners planned and resumed mass drug administration (MDA) in mid-August to September 2020 in 19 health districts. A risk-benefit assessment was conducted to identify potential risks associated with the MDA in the COVID-19 context. Following this assessment, a risk mitigation plan with barrier measures was developed to guide MDA implementation. These measures included COVID-19 testing for all national staff leaving Conakry, mask wearing, social distancing of two meters, and hand washing/sanitizing. A checklist was developed and used to monitor compliance to risk mitigation measures. Data on adherence to risk mitigation measures were collected electronically during the MDA. A total of 120 checklists, representing 120 community drug distributor (CDD) teams (two CDDs per team) and 120 households, were completed. Results indicated that washing or disinfecting hands was practiced by 68.3% of CDD teams, compared to 45.0% among households. Face masks to cover the mouth and nose were worn by 79.2% of CDD teams, while this was low among households (23.3%). In 87.5% of households, participants did not touch the dose pole and in 88.3% of CDD teams, CDDs did not touch the hands of the participants while giving the drugs. A large majority of CDD teams (94.2%) and household members (94.2%) were willing to participate in the MDA despite the pandemic. The epidemiological coverage was ≥65% for lymphatic filariasis, onchocerciasis and soil-transmitted helminths in 10 out of 19 HDs and ≥75% for schistosomiasis for school-aged children in 7 out of 11 HDs. Guinea was one of the first countries in Africa to resume MDA activities during the COVID-19 pandemic without causing an observed increase of transmission. The development of a risk mitigation plan and a method to monitor adherence to barrier measures was critical to this unprecedented effort. The rapid incorporation of COVID-19 barrier measures and their acceptance by CDDs and household members demonstrated both the adaptability of the National NTD Program to respond to emerging issues and the commitment of the MoH to implement NTD programs.

Health Economics Study: Epidemiological, Socioeconomic and Health Service Coverage Indicators in a State in the Western Amazon (Brazil)

Health Economics Study: Epidemiological, Socioeconomic and Health Service Coverage Indicators in a State in the Western Amazon (Brazil)

Achievements and challenges of lymphatic filariasis elimination in Sierra Leone.

Lymphatic filariasis (LF) is targeted for elimination in Sierra Leone. Epidemiological coverage of mass drug administration (MDA) with ivermectin and albendazole had been reported >65% in all 12 districts annually. Eight districts qualified to implement transmission assessment survey (TAS) in 2013 but were deferred until 2017 due to the Ebola outbreak (2014-2016). In 2017, four districts qualified for conducting a repeat pre-TAS after completing three more rounds of MDA and the final two districts were also eligible to implement a pre-TAS. For TAS, eight districts were surveyed as four evaluation units (EU). A school-based survey was conducted in children aged 6-7 years from 30 clusters per EU. For pre-TAS, one sentinel and one spot check site per district (with 2 spot check sites in Bombali) were selected and 300-350 persons aged 5 years and above were selected. For both surveys, finger prick blood samples were tested using the Filariasis Test Strips (FTS). For TAS, 7,143 children aged 6-7 years were surveyed across four EUs, and positives were found in three EUs, all below the critical cut-off value for each EU. For the repeat pre-TAS/pre-TAS, 3,994 persons over five years of age were surveyed. The Western Area Urban had FTS prevalence of 0.7% in two sites and qualified for TAS, while other five districts had sites with antigenemia prevalence >2%: 9.1-25.9% in Bombali, 7.5-19.4% in Koinadugu, 6.1-2.9% in Kailahun, 1.3-2.3% in Kenema and 1.7% - 3.7% in Western Area Rural. Eight districts in Sierra Leone have successfully passed TAS1 and stopped MDA, with one more district qualified for conducting TAS1, a significant progress towards LF elimination. However, great challenges exist in eliminating LF from the whole country with repeated failure of pre-TAS in border districts. Effort needs to be intensified to achieve LF elimination.

A community survey of coverage and adverse events following country-wide triple-drug mass drug administration for lymphatic filariasis elimination, Samoa 2018.

The Global Programme to Eliminate Lymphatic Filariasis has made considerable progress but is experiencing challenges in meeting targets in some countries. Recent World Health Organization guidelines have recommended two rounds of triple-drug therapy with ivermectin, diethylcarbamazine (DEC), and albendazole (IDA), in areas where mass drug administration (MDA) results with two drugs (DEC and albendazole) have been suboptimal, as is the case in Samoa. In August 2018, Samoa was the first country in the world to implement countrywide triple-drug MDA. This paper aims to describe Samoa’s experience with program coverage and adverse events (AEs) in the first round of triple-drug MDA. We conducted a large cross-sectional community survey to assess MDA awareness, reach, compliance, coverage and AEs in September/October 2018, 7–11 weeks after the first round of triple-drug MDA. In our sample of 4420 people aged ≥2 years (2.2% of the population), age-adjusted estimates indicated that 89.0% of the eligible population were offered MDA, 83.9% of the eligible population took MDA (program coverage), and 80.2% of the total population took MDA (epidemiological coverage). Overall, 83.8% (2986/3563) reported that they did not feel unwell at all after taking MDA. Mild AEs (feeling unwell but able to do normal everyday things) were reported by 13.3% (476/3563) and moderate or severe AEs (feeling unwell and being unable to do normal everyday activities such as going to work or school) by 2.9% (103/3563) of participants. This study following the 2018 triple-drug MDA in Samoa demonstrated a high reported program awareness and reach of 90.8% and 89.0%, respectively. Age-adjusted program coverage of 83.9% of the total population showed that MDA was well accepted and well tolerated by the community.

Household spraying in cholera outbreaks: Insights from three exploratory, mixed-methodsfield effectiveness evaluations.

Household spraying is a commonly implemented, yet an under-researched, cholera response intervention where a response team sprays surfaces in cholera patients’ houses with chlorine. We conducted mixed-methods evaluations of three household spraying programs in the Democratic Republic of Congo and Haiti, including 18 key informant interviews, 14 household surveys and observations, and 418 surface samples collected before spraying, 30 minutes and 24 hours after spraying. The surfaces consistently most contaminated with Vibrio cholerae were food preparation areas, near the patient’s bed and the latrine. Effectiveness varied between programs, with statistically significant reductions in V. cholerae concentrations 30 minutes after spraying in two programs. Surface contamination after 24 hours was variable between households and programs. Program challenges included difficulty locating households, transportation and funding limitations, and reaching households quickly after case presentation (disinfection occurred 2–6 days after reported cholera onset). Program advantages included the concurrent deployment of hygiene promotion activities. Further research is indicated on perception, recontamination, cost-effectiveness, viable but nonculturable V. cholerae, and epidemiological coverage. We recommend that, if spraying is implemented, spraying agents should: disinfect surfaces systematically until wet using 0.2/2.0% chlorine solution, including kitchen spaces, patients’ beds, and latrines; arrive at households quickly; and, concurrently deploy hygiene promotion activities.

The roles of stakeholder experience and organizational learning in declining mass drug administration coverage for lymphatic filariasis in Port-au-Prince, Haiti: A case study.

The World Health Organization (WHO) defines an effective round of mass drug administration (MDA) for lymphatic filariasis (LF) as one that reaches at least 65% of the target population. In its first round of MDA in 2011–2012, the National Program to Eliminate LF in Haiti achieved a 79% epidemiological coverage in urban Port-au-Prince. In 2013, coverage dropped below the WHO threshold and has declined year-over-year to a low of 41% in 2017. We conducted a retrospective qualitative case study to identify key factors behind the decline in coverage in Port-au-Prince and ways to address them. Our findings suggest that the main contributors to the decline in MDA coverage appear to be the absence of effective documentation of practices, reporting, analysis, and program quality improvement—i.e., learning mechanisms—within the program’s MDA design and implementation strategy. In addition to their contribution to the program’s failure to meet its coverage targets, these deficits have resulted in a high cost for the MDA campaign in both lost momentum and depleted morale. Through a proposed operating logic model, we explore how the pathway from program inputs to outcomes is influenced by a wide array of mediating factors, which shape potential participants’ experience of MDA and, in turn, influence their reasoning and decisions to take, or not take, the pills. Our model suggests that the decisions and behavior of individuals are a reflection of their overall experience of the program itself, mediated through a host of contextual factors, and not simply the expression of a fixed choice or preference. This holistic approach offers a novel and potentially valuable framing for the planning and evaluation of MDA strategies for LF and other diseases, and may be applicable in a variety of global health programs.

Are census data accurate for estimating coverage of a lymphatic filariasis MDA campaign? Results of a survey in Sierra Leone.

BackgroundPreventive chemotherapy was administered to 3.2 million Sierra Leoneans in 13 health districts for lymphatic filariasis, onchocerciasis, and soil transmitted helminthes from October 2008 to February 2009. This paper aims to report the findings of a coverage survey conducted in 2009, compare the coverage survey findings with two reported rates for lymphatic filariasis coverage obtained using pre-mass drug administration (MDA) registration and national census projections, and use the comparison to understand the best source of population estimates in calculating coverage for NTD programming in Sierra Leone.Methodology/Principal findingsCommunity drug distributors (CDDs) conducted a pre- MDA registration of the population. Two coverage rates for MDA for lymphatic filariasis were subsequently calculated using the reported number treated divided by the total population from: 1) the pre-MDA register and 2) national census projections. A survey was conducted to validate reported coverage data. 11,602 persons participated (response rate of 76.8%). Overall, reported coverage data aggregated to the national level were not significantly different from surveyed coverage (z-test >0.05). However, estimates based on pre-MDA registration have higher agreement with surveyed coverage (mean Kendall’s W = 0.68) than coverage calculated with census data (mean Kendall’s = 0.59), especially in districts with known large-scale migration, except in a highly urban district where it was more challenging to conduct a pre-MDA registration appropriately. There was no significant difference between coverage among males versus females when the analyses were performed excluding those women who were pregnant at the time of MDA. The surveyed coverage estimate was near or below the minimum 65% epidemiological coverage target for lymphatic filariasis MDA in all districts.Conclusion/SignificanceThese results from Sierra Leone illustrate the importance of choosing the right denominator for calculating treatment coverage for NTD programs. While routinely reported coverage results using national census data are often good enough for programmatic decision making, census projections can quickly become outdated where there is substantial migration, e.g. due to the impact of civil war, with changing economic opportunities, in urban settings, and where there are large migratory populations. In districts where this is known to be the case, well implemented pre-MDA registration can provide better population estimates. Pre-MDA registration should, however, be implemented correctly to reduce the risk of missing pockets of the population, especially in urban settings.

Burden of illness of follicular lymphoma and marginal zone lymphoma.

Follicular lymphoma (FL) and marginal zone lymphoma (MZL) are two subtypes of indolent B cell non-Hodgkin lymphoma (NHL) that account for approximately 20% and 12% of all NHLs, respectively. FL and MZL are rare conditions with orphan disease designations. We conducted a comprehensive review of the burden of FL and MZL that encompasses the epidemiological, real world clinical, economic, and humanistic impact of these diseases globally. A targeted literature search identified 31 eligible studies for review. Epidemiological coverage was poor, with data obtained for studies from only seven countries. The incidences of both subtypes were low: age-standardized incidence rates of FL ranged from 2.1/100,000 in France to 4.3/100,000 in the USA, while for MZL it varied geographically from 0.5/100,000 in Australia to 2.6/100,000 in the UK. The cumulative total direct healthcare costs for FL were higher for patients with progressive disease compared to those without ($30,890 vs. $8704 at 12months, respectively) and main driver of costs related to the use of chemotherapy. Five-year overall survival was improved in patients with FL compared with MZL (e.g., 76.5% vs 60.7% in one study that reported on both subtypes). Mortality rates were particularly lower in female patients with FL aged < 60years. However, limited outcome data for MZL patients were identified. FL and MZL contribute significant burden on healthcare systems and on patients globally, with delays in progression potentially leading to cost savings. More rigorous characterization of these two NHL subtypes, new and more effective treatments, and standardization of reporting would lead to a more robust understanding of future data in this disease area.

Estimating the contribution of key populations towards the spread of HIV in Dakar, Senegal.

IntroductionKey populations including female sex workers (FSW) and men who have sex with men (MSM) bear a disproportionate burden of HIV. However, the role of focusing prevention efforts on these groups for reducing a country's HIV epidemic is debated. We estimate the extent to which HIV transmission among FSW and MSM contributes to overall HIV transmission in Dakar, Senegal, using a dynamic assessment of the population attributable fraction (PAF).MethodsA dynamic transmission model of HIV among FSW, their clients, MSM and the lower‐risk adult population was parameterized and calibrated within a Bayesian framework using setting‐specific demographic, behavioural, HIV epidemiological and antiretroviral treatment (ART) coverage data for 1985 to 2015. We used the model to estimate the 10‐year PAF of commercial sex between FSW and their clients, and sex between men, to overall HIV transmission (defined as the percentage of new infections prevented when these modes of transmission are removed). In addition, we estimated the prevention benefits associated with historical increases in condom use and ART uptake, and impact of further increases in prevention and treatment.ResultsThe model projections suggest that unprotected sex between men contributed to 42% (2.5 to 97.5th percentile range 24 to 59%) of transmissions between 1995 and 2005, increasing to 64% (37 to 79%) from 2015 to 2025. The 10‐year PAF of commercial sex is smaller, diminishing from 21% (7 to 39%) in 1995 to 14% (5 to 35%) in 2015. Without ART, 49% (32 to 71%) more HIV infections would have occurred since 2000, when ART was initiated, whereas without condom use since 1985, 67% (27 to 179%) more HIV infections would have occurred, and the overall HIV prevalence would have been 60% (29 to 211%) greater than what it is now. Further large decreases in HIV incidence (68%) can be achieved by scaling up ART in MSM to 74% coverage and reducing their susceptibility to HIV by two‐thirds through any prevention modality.ConclusionsUnprotected sex between men may be an important contributor to HIV transmission in Dakar, due to suboptimal coverage of evidence‐informed interventions. Although existing interventions have effectively reduced HIV transmission among adults, it is crucial that further strategies address the unmet need among MSM.

How elimination of lymphatic filariasis as a public health problem in the Kingdom of Cambodia was achieved

BackgroundEndemicity of lymphatic filariasis (LF) in Cambodia was proven in 1956 when microfilariae were detected in mosquitos in the Kratié province. In 2001, an extensive study confirmed the presence of both Brugia malayi and Wuchereria bancrofti microfilariae. In 2003, the Ministry of Health established a national task force to develop policies and strategies for controlling and eliminating neglected tropical diseases (NTDs), with the goal of eliminating LF by 2015. This article summarizes the work accomplished to eliminate LF as a public health problem in Cambodia.MethodsThe National Program to Eliminate Lymphatic Filariasis made excellent progress in the goal towards elimination due to strong collaboration between ministries, intensive supervision by national staff, and advocacy for mobilization of internal and external resources. Mass drug administration (MDA) with diethylcarbamazine citrate and albendazole was conducted in six implementation units, achieving > 70% epidemiological coverage for five consecutive rounds, from 2005 to 2009. In 2006, in 14 provinces, healthcare workers developed a line list of lymphedema and hydrocele patients, many of whom were > 40 years old and had been affected by LF for many years. The national program also trained healthcare workers and provincial and district staff in morbidity management and disability prevention, and designated health centers to provide care for lymphedema and acute attack. Two reference hospitals were designated to administer hydrocele surgery.ResultsEffectiveness of MDA was proven with transmission assessment surveys. These found that less than 1% of school children had antigenemia in 2010, which fell to 0% in both 2013 and 2015. A separate survey in one province in 2015 using Brugia Rapid tests to test for LF antibody found one child positive among 1677 children. The list of chronic LF patients was most recently updated and confirmed in 2011–2012, with 32 lymphoedema patients and 17 hydrocele patients listed. All lymphedema patients had been trained on self-management and all hydrocele patients had been offered free surgery.ConclusionsDue to the success of the MDA and the development of health center capacity for patient care, along with benefits gained from socioeconomic improvements and other interventions against vector-borne diseases and NTDs, Cambodia was validated by the World Health Organization as achieving LF elimination as a public health problem in 2016.

Reaching endpoints for lymphatic filariasis elimination- results from mass drug administration and nocturnal blood surveys, South Gujarat, India.

BackgroundFollowing the World Health Assembly resolution on Elimination of lymphatic filariasis (ELF) as a public health problem by the year 2020, a Global Program (GPELF) was launched in 1997 to help endemic countries to initiate national programs. The current strategy to interrupt transmission of LF, is administration of once-yearly, single-dose, two-drug regimen (Albendazole with Diethylcarbamazine (DEC) to be used in endemic areas with the goal of reaching 65% epidemiological coverage for 4–6 years. We report findings of independent assessment from year 2010 to 2015 for last six rounds, after initial five rounds of Mass Drug Administration (MDA) since 2005 for ELF in endemic area of Gujarat.MethodsIndependent assessment of MDA was performed to find coverage and compliance indicators, reasons for non-coverage and non-compliance in five Implementation Units (IUs). Pre, during and post MDA evaluations were done in three phases. The impact of MDA was measured by microfilaraemia survey. A total of eight sites, four random and four fixed sentinel sites were selected to calculate microfilaria rate (MF) per IUs per year. In years 2010 to 2015, we report results from 125,936 nocturnal blood smears and 17551 population in 120 selected clusters. Four clusters were selected per year in each of the five IUs for assessment of MDA round.ResultPost MDA survey showed drug coverage between 81%-88% and epidemiological coverage 77%-89% across years. Main reasons for non-coverage were drug administrator related (the team did not visit or missed people) while non-compliance was population related (fear of side effects, sickness, people forgot or absent). During MDA findings show that the directly observed consumption is considerably improved from 58% in 2010 to 82% in 2015. The knowledge about benefits of drug provided also increased from 59% to 90% over the years. The current MF rate is less than one in all IUs with an overall 68% percent decrease from baseline year 2005 to year 2015. The average MF rate of Gujarat is 0.44 for year 2015.ConclusionsThe findings show that achieving adequate epidemiological and drug coverage is possible by actual field level operation of the program in large endemic areas. The results and feedback from independent assessment, performed regularly, could guide the policymakers and program managers for mid-term corrections and to frame strategies to enhance program. Monitoring of coverage and impact indicator together informs decisions for reaching end-point of MDA. The impact indicator- microfilaria rate in all IUs of South Gujarat Region has reached and remained less than one percent signaling end-points of MDA. Post MDA stringent monitoring in form of TAS is recommended to keep vigil on maintenance of elimination achieved.

Controlling Neglected Tropical Diseases (NTDs) in Haiti: Implementation Strategies and Evidence of Their Success.

Lymphatic filariasis (LF) and soil-transmitted helminths (STH) have been targeted since 2000 in Haiti, with a strong mass drug administration (MDA) program led by the Ministry of Public Health and Population and its collaborating international partners. By 2012, Haiti’s neglected tropical disease (NTD) program had reached full national scale, and with such consistently good epidemiological coverage that it is now able to stop treatment for LF throughout almost all of the country. Essential to this success have been in the detail of how MDAs were implemented. These key programmatic elements included ensuring strong community awareness through an evidence-based, multi-channel communication and education campaign facilitated by voluntary drug distributors; strengthening community trust of the drug distributors by ensuring that respected community members were recruited and received appropriate training, supervision, identification, and motivation; enforcing a “directly observed treatment” strategy; providing easy access to treatment though numerous distribution posts and a strong drug supply chain; and ensuring quality data collection that was used to guide and inform MDA strategies. The evidence that these strategies were effective lies in both the high treatment coverage obtained– 100% geographical coverage reached in 2012, with almost all districts consistently achieving well above the epidemiological coverage targets of 65% for LF and 75% for STH—and the significant reduction in burden of infection– 45 communes having reached the target threshold for stopping treatment for LF. By taking advantage of sustained international financial and technical support, especially during the past eight years, Haiti’s very successful MDA campaign resulted in steady progress toward LF elimination and development of a strong foundation for ongoing STH control. These efforts, as described, have not only helped establish the global portfolio of “best practices” for NTD control but also are poised to help solve two of the most important future NTD challenges—how to maintain control of STH infections after the community-based LF “treatment platform” ceases and how to ensure appropriate morbidity management for patients currently suffering from lymphatic filarial disease.

Are we nearly there yet? Coverage and compliance of mass drug administration for lymphatic filariasis elimination.

Lymphatic filariasis has been targeted for elimination by 2020, and a threshold of 65% coverage of mass drug administration (MDA) has been adopted by the Global Programme to Eliminate Lymphatic Filariasis (GPELF). A recent review by Babu and Babu of 36 studies of MDA for lymphatic filariasis in India found that coverage, defined as receipt of tablets, ranged from 48.8 to 98.8%, while compliance, defined as actual ingestion of tablets, was 22% lower on average. Moreover, the denominator for these coverage figures is the eligible, rather than total, population. By contrast, the 65% threshold, in the original modelling study, refers to ingestion of tablets in the total population. This corresponds to GPELF's use of ‘epidemiological drug coverage’ as a trigger for the Transmission Assessment Surveys (TAS), which indicate whether to proceed to post-MDA surveillance. The existence of less strict definitions of ‘coverage’ should not lead to premature TAS that could impair MDA's sustainability.