scholarly journals A Step Toward Eradication of Human Filariases in Areas Where Loa Is Endemic

mBio ◽  
2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Timothy G. Geary

ABSTRACT Mass drug administration (MDA) programs have achieved remarkable success in limiting the pathology and transmission of the human parasitic infections onchocerciasis and lymphatic filariasis. The full implementation of MDA campaigns for filariasis elimination has been stymied by the unacceptable incidence of severe adverse events observed following drug treatment of a subset of individuals who harbor high loads of Loa loa microfilaria. Extending MDA strategies to regions where loiasis is coendemic could be done confidently if a simple, inexpensive, and rapid diagnostic method was available that could accurately identify individuals who have L. loa microfilarial loads above the risk threshold and could thus be excluded from treatment. A recent paper in mBio reports the discovery of an antigen unique to L. loa microfilaria that can be detected in blood and urine and may form the basis for such an assay. Further work will reveal whether this discovery will smooth the path to achieve filariasis eradication.

Author(s):  
David J Blok ◽  
Joseph Kamgno ◽  
Sebastien D Pion ◽  
Hugues C Nana-Djeunga ◽  
Yannick Niamsi-Emalio ◽  
...  

Abstract Background Mass drug administration (MDA) with ivermectin is the main strategy for onchocerciasis elimination. Ivermectin is generally safe but associated with serious adverse events in individuals with high Loa loa microfilarial densities (MFD). Therefore, ivermectin MDA is not recommended in areas where onchocerciasis is hypo-endemic and L. loa is co-endemic. To eliminate onchocerciasis in those areas, a test-and-not-treat (TaNT) strategy has been proposed. We investigated whether onchocerciasis elimination can be achieved using TaNT and the required duration. Methods We used the individual-based model ONCHOSIM to predict the impact of TaNT on onchocerciasis microfilarial (mf) prevalence. We simulated pre-control mf prevalence levels from 2-40%. The impact of TaNT was simulated under varying levels of participation, systematic non-participation and exclusion from ivermectin due to high L. loa MFD. For each scenario, we assessed the time to elimination, defined as bringing onchocerciasis mf prevalence below 1.4%. Results In areas with 30-40% pre-control mf prevalence, the model predicted that it would take between 14 and 16 years to bring the mf prevalence below 1.4% using conventional MDA, assuming 65% participation. TaNT would increase the time to elimination by up to 1.5 years, depending on the level of systematic non-participation and the exclusion rate. At lower exclusion rates (≤2.5%), the delay would be less than six months. Conclusions Our model predicts that onchocerciasis can be eliminated using TaNT in L. loa co-endemic areas. The required treatment duration using TaNT would be only slightly longer than in areas with conventional MDA, provided that participation is good.


2020 ◽  
Vol 14 (11) ◽  
pp. e0008854
Author(s):  
Gabriela A. Willis ◽  
Helen J. Mayfield ◽  
Therese Kearns ◽  
Take Naseri ◽  
Robert Thomsen ◽  
...  

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.


2021 ◽  
Vol 6 (2) ◽  
pp. 44
Author(s):  
Patricia M. Graves ◽  
Sarah Sheridan ◽  
Jessica Scott ◽  
Filipina Amosa-Lei Sam ◽  
Take Naseri ◽  
...  

Following the first triple-drug mass drug administration (MDA) for lymphatic filariasis in Samoa in 2018, unexpected persistence of microfilaria (Mf) positivity in 18 (15%) of 121 antigen-positive persons was observed in a nationwide household survey 1–2 months later. Of the 18 Mf positive persons, 14 reported taking the MDA, raising concerns about MDA efficacy. In 2019, 5–6 months after the 2018 survey, a monitored treatment study was done to evaluate directly observed weight-based treatment in these Mf positive individuals. Mf presence and density were assessed before and 7 days after treatment, using 1 mL membrane filtered venous blood, and 60uL thick blood films on slides prepared from venous or fingerprick blood. All 14 participants were still Mf positive on filters from venous blood pre-treatment samples, but two were negative by slide made from the same samples. Mf were cleared completely by day 7 in 12 of 13 participants followed up, and by day 30 in the remaining participant. Filtered blood using EDTA samples (to reduce clumping of Mf) is preferred over slides alone for improving the likelihood of detecting Mf and estimating their density. The triple-drug MDA strategy was effective at clearing Mf when given and taken at the correct dose.


2020 ◽  
Vol 13 (Supplement_1) ◽  
pp. S60-S64
Author(s):  
Gary J Weil ◽  
Julie A Jacobson ◽  
Jonathan D King

Abstract 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.


2020 ◽  
Author(s):  
Gabriela A. Willis ◽  
Helen Mayfield ◽  
Therese Kearns ◽  
Take Naseri ◽  
Robert Thomsen ◽  
...  

AbstractBackgroundThe Global Programme to Eliminate Lymphatic Filariasis is making considerable progress but has experienced 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 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.Methodology/Principal findingsWe assessed MDA awareness, reach, compliance, coverage and AEs from three different data sources: a Supervisor’s Coverage Tool (SCT) in three villages; a large cross-sectional community survey in September/October 2018, 7-11 weeks after the first round of triple-drug MDA; and AE surveillance conducted by the Ministry of Health, Samoa. Participants aged ≥5 years had a fingerprick blood sample tested for circulating filarial antigen using the Alere Filariasis Test Strip. Data were analysed descriptively. In our sample of 4420 people (2.2% of the population), age-adjusted estimates indicated that 89.0% of the eligible population were offered MDA and 80.2% of the total population took MDA. Mild AEs were reported by 13.3% and moderate/severe AEs by 2.9% of participants.Conclusions/SignificanceThis study following the 2018 triple-drug MDA in Samoa demonstrated a high reported program awareness and reach of 90.8% and 89.0%, respectively. Coverage of 80.2% of the total population showed that MDA was well accepted and well tolerated by the community.Author summaryLymphatic filariasis is a mosquito transmitted worm disease. A global program underway aims to eliminate lymphatic filariasis as a public health problem by distributing deworming drugs to the whole population once a year for at least five years. In some countries, including Samoa, this strategy has not been sufficient to eliminate transmission. A new drug has been added, and in 2018, Samoa was the first country in the world to apply triple drug mass drug administration using ivermectin, diethylcarbamazine, and albendazole. This study reports on the coverage achieved (percentage of people who reported taking the drugs) and adverse events after taking the drugs. Data were obtained from three different sources. A large community survey of over 4000 people, done 7-11 weeks after the distribution of the first round, found that the program reached and offered MDA to approximately 90% of the whole population, and approximately 80% of the whole population swallowed the drugs. Findings from the community survey on participation in the MDA program were consistent with those from the WHO recommended Supervisor’s Coverage Tool, a smaller survey which was undertaken in three villages by the Samoan Ministry of Health. Data on AEs related to MDA were collected during the community survey, and also through a system set up by the Ministry of Health to enable community members to report any problems related to MDA and receive advice on managing problems. There were relatively few adverse events reported and most of them were mild and of short duration.


2020 ◽  
Vol 102 (1) ◽  
pp. 96-99 ◽  
Author(s):  
Vijesh Sreedhar Kuttiatt ◽  
Roopali K. Somani ◽  
Subramanian Swaminathan ◽  
Kaliannagounder Krishnamoorthy ◽  
Gary J. Weil ◽  
...  

2020 ◽  
Vol 20 (2) ◽  
pp. 167-174
Author(s):  
Ilo Dicko ◽  
Yaya Ibrahim Coulibaly ◽  
Modibo Sangaré ◽  
Bismark Sarfo ◽  
Priscillia Awo Nortey

Background: Lymphatic filariasis (LF) is a parasitic disease that has been targeted for elimination through the Mass Drug Administration (MDA.) Although the MDA started in the Ankobra community in Ghana in 2000, LF prevalence as reported in 2014 was relatively high (4.5%). Non-compliance to the MDA has been associated with the persistent LF prevalence in endemic regions. Objective: This study determined the factors associated with the non-compliance to the MDA among patients living in the Ankobra community, Ghana. Methods: A cross-sectional study using a one-stage cluster sampling method was used to collect data between June and July, 2017 in Ankobra. Questionnaires were used to collect data from health workers, the MDA drug distributors and study participants in Ankobra. Data analysis was performed using STATA 14. Logistic regression was used to measure the degree of association between the dependent (non-compliance) and independent variables. Non-compliance rate was defined as the percentage of individuals who self-reported that they did not actually swallow the drugs provided during the MDA. Results: The MDA coverage and non-compliance rates were 73.5% (147/200) and 33.33% (49/147) respectively. The main reason for non-compliance was fear of drug adverse events (75.51%, 37/49). Thought of “not being susceptible to LF” was significantly associated with the non-compliance (aOR= 2.83, [CI= 1.15, 6.98]). Conclusion: Health education about the susceptibility of residents getting LF disease in endemic community must be intensified to improve compliance to MDA medication ingestion and thus meet the Global Elimination of Lymphatic Filariasis by 2020.


2021 ◽  
Vol 49 (1) ◽  
Author(s):  
Alfred Kwesi Manyeh ◽  
Tobias Chirwa ◽  
Rohit Ramaswamy ◽  
Frank Baiden ◽  
Latifat Ibisomi

Abstract Background Over 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. Method A 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. Results The 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. Conclusion The 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.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Eliza Lupenza ◽  
Dinah B. Gasarasi ◽  
Omary M. Minzi

Abstract Background Lymphatic filariasis (LF) elimination program in Tanzania started in 2000 in response to the Global program for the elimination of LF by 2020. Evidence shows a persistent LF transmission despite more than a decade of mass drug administration (MDA). It is advocated that, regular monitoring should be conducted in endemic areas to evaluate the progress towards elimination and detect resurgence of the disease timely. This study was therefore designed to assess the status of Wuchereria bancrofti infection in Culex quinqefasciatus and Anopheles species after six rounds of MDA in Masasi District, South Eastern Tanzania. Methods Mosquitoes were collected between June and July 2019 using Center for Diseases Control (CDC) light traps and gravid traps for indoor and outdoor respectively. The collected mosquitoes were morphologically identified into respective species. Dissections and PCR were carried out to detect W. bancrofti infection. Questionnaire survey and checklist were used to assess vector control interventions and household environment respectively. A Poisson regression model was run to determine the effects of household environment on filarial vector density. Results Overall, 12 452 mosquitoes were collected of which 10 545 (84.7%) were filarial vectors. Of these, Anopheles gambiae complex, An. funestus group and Cx. quinquefasciatus accounted for 0.1%, 0.7% and 99.2% respectively. A total of 365 pools of Cx. quinquefasciatus (each with 20 mosquitoes) and 46 individual samples of Anopheles species were analyzed by PCR. For Cx. quinquefasciatus pools, 33 were positive for W. bancrofti, giving an infection rate of 0.5%, while the 46 samples of Anopheles species were all negative. All 1859 dissected mosquitoes analyzed by microscopy were also negative. Households with modern latrines had less mosquitoes than those with pit latrines [odds ratio (OR) = 0.407, P < 0.05]. Houses with unscreened windows had more mosquitoes as compared to those with screened windows (OR = 2.125, P < 0.05). More than 80% of the participants own bednets while 16.5% had no protection. Conclusions LF low transmission is still ongoing in Masasi District after six rounds of MDA and vector control interventions. The findings also suggest that molecular tools may be essential for xenomonitoring LF transmission during elimination phase.


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