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1.
Clin Infect Dis ; 72(12): e1047-e1055, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33289025

RESUMO

BACKGROUND: Mass drug administration (MDA) with ivermectin is the main strategy for onchocerciasis elimination. Ivermectin is generally safe, but is 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 precontrol mf prevalence levels from 2% to 40%. The impact of TaNT was simulated under varying levels of participation, systematic nonparticipation, and exclusion from ivermectin resulting from 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% to 40% precontrol 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 nonparticipation and the exclusion rate. At lower exclusion rates (≤2.5%), the delay would be less than 6 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.


Assuntos
Loíase , Oncocercose , Animais , Estudos de Viabilidade , Humanos , Ivermectina/uso terapêutico , Loa , Loíase/diagnóstico , Loíase/tratamento farmacológico , Loíase/epidemiologia , Oncocercose/tratamento farmacológico , Oncocercose/epidemiologia , Oncocercose/prevenção & controle , Prevalência
2.
Lancet ; 394(10192): 81-92, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31178154

RESUMO

Scabies is a parasitic disease of the skin that disproportionately affects disadvantaged populations. The disease causes considerable morbidity and leads to severe bacterial infection and immune-mediated disease. Scientific advances from the past 5 years suggest that scabies is amenable to population-level control, particularly through mass drug administration. In recognition of these issues, WHO added scabies to the list of neglected tropical diseases in 2017. To develop a global control programme, key operational research questions must now be addressed. Standardised approaches to diagnosis and methods for mapping are required to further understand the burden of disease. The safety of treatments for young children, including with ivermectin and moxidectin, should be investigated. Studies are needed to inform optimum implementation of mass treatment, including the threshold for intervention, target, dosing, and frequency. Frameworks for surveillance, monitoring, and evaluation of control strategies are also necessary.


Assuntos
Doenças Negligenciadas/prevenção & controle , Escabiose/prevenção & controle , Saúde Global , Humanos , Administração Massiva de Medicamentos , Vigilância da População , Saúde Pública , Organização Mundial da Saúde
3.
N Engl J Med ; 377(21): 2044-2052, 2017 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-29116890

RESUMO

BACKGROUND: Implementation of an ivermectin-based community treatment strategy for the elimination of onchocerciasis or lymphatic filariasis has been delayed in Central Africa because of the occurrence of serious adverse events, including death, in persons with high levels of circulating Loa loa microfilariae. The LoaScope, a field-friendly diagnostic tool to quantify L. loa microfilariae in peripheral blood, enables rapid, point-of-care identification of persons at risk for serious adverse events. METHODS: A test-and-not-treat strategy was used in the approach to ivermectin treatment in the Okola health district in Cameroon, where the distribution of ivermectin was halted in 1999 after the occurrence of fatal events related to L. loa infection. The LoaScope was used to identify persons with an L. loa microfilarial density greater than 20,000 microfilariae per milliliter of blood, who were considered to be at risk for serious adverse events, and exclude them from ivermectin distribution. Active surveillance for posttreatment adverse events was performed daily for 6 days. RESULTS: From August through October 2015, a total of 16,259 of 22,842 persons 5 years of age or older (71.2% of the target population) were tested for L. loa microfilaremia. Among the participants who underwent testing, a total of 15,522 (95.5%) received ivermectin, 340 (2.1%) were excluded from ivermectin distribution because of an L. loa microfilarial density above the risk threshold, and 397 (2.4%) were excluded because of pregnancy or illness. No serious adverse events were observed. Nonserious adverse events were recorded in 934 participants, most of whom (67.5%) had no detectable L. loa microfilariae. CONCLUSIONS: The LoaScope-based test-and-not-treat strategy enabled the reimplementation of community-wide ivermectin distribution in a heretofore "off limits" health district in Cameroon and is a potentially practical approach to larger-scale ivermectin treatment for lymphatic filariasis and onchocerciasis in areas where L. loa infection is endemic. (Funded by the Bill and Melinda Gates Foundation and others.).


Assuntos
Antiparasitários/uso terapêutico , Doenças Endêmicas , Ivermectina/uso terapêutico , Loa/isolamento & purificação , Loíase/diagnóstico , Oncocercose/tratamento farmacológico , Adolescente , Adulto , Idoso , Animais , Antiparasitários/efeitos adversos , Sangue/parasitologia , Camarões , Criança , Filariose Linfática/complicações , Filariose Linfática/tratamento farmacológico , Feminino , Humanos , Ivermectina/efeitos adversos , Modelos Logísticos , Loíase/complicações , Loíase/epidemiologia , Masculino , Microfilárias/isolamento & purificação , Microscopia de Vídeo/instrumentação , Pessoa de Meia-Idade , Oncocercose/complicações
4.
BMC Public Health ; 20(1): 871, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503495

RESUMO

BACKGROUND: Epilepsy is a severe neurological disorder with huge psychological, social, and economic consequences, including premature deaths and loss of productivity. Sub-Saharan Africa carries the highest burden of epilepsy. The management of epilepsy in Cameroon remains unsatisfactory due to poor identification of cases and a limited knowledge of the distribution of the disease. The objective of this study was to determine whether community drug distributors (CDDs) - volunteers selected by their communities to distribute ivermectin against onchocerciasis and who have been proven efficient to deliver other health interventions such as insecticide-treated bed nets to prevent malaria, vitamin A tablets, and albendazole to treat soil transmitted helminthiasis - can be used to reliably identify people living with epilepsy to promote better management of cases. METHODS: This study was carried out in three health Districts in Cameroon. An exhaustive house to house census was carried out by trained CDDs under the supervision of local nurses. In each household, all suspected cases of epilepsy were identified. In each health district, five communities were randomly selected for a second census by trained health personnel (research team). The results of the two censuses were compared for verification purposes. RESULTS: A total of 53,005 people was registered in the 190 communities surveyed with 794 (1.4%) individuals identified as suspected cases of epilepsy (SCE) by the CDDs. In the 15 communities where the SCE census was verified, the average ratio between the number of suspected cases of epilepsy reported in a community by the research team and that reported by the CDDs was 1.1; this ratio was < 0.8 and > 1.2 in 6 communities. CONCLUSIONS: The results of this study suggest that CDDs, who are present in about 200,000 communities in 31 Sub Saharan African countries where onchocerciasis is endemic, can be successfully used to assess epilepsy prevalence, and therefore map epilepsy in many African countries.


Assuntos
Censos , Serviços de Saúde Comunitária/métodos , Epilepsia/epidemiologia , Inquéritos Epidemiológicos/métodos , População Rural/estatística & dados numéricos , Adolescente , Adulto , Camarões/epidemiologia , Características da Família , Feminino , Humanos , Masculino , Prevalência , Reprodutibilidade dos Testes , Voluntários , Adulto Jovem
5.
Clin Infect Dis ; 69(9): 1628-1630, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30861060

RESUMO

The specificity of skin snips for onchocerciasis diagnoses is considered to be almost 100%. Our molecular methods revealed that microfilariae emerging from skin snips collected from highly microfilaremic Loa loa-infected individuals were largely misidentified as Onchocerca volvulus. This has important implications for onchocerciasis diagnostic testing in Loa-endemic areas.


Assuntos
Loa/patogenicidade , Loíase/parasitologia , Microfilárias/parasitologia , Oncocercose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Feminino , Humanos , Loíase/metabolismo , Masculino , Microfilárias/metabolismo , Pessoa de Meia-Idade , Onchocerca volvulus/patogenicidade , Oncocercose/metabolismo , Adulto Jovem
6.
BMC Public Health ; 18(1): 201, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382314

RESUMO

BACKGROUND: Lymphatic filariasis (LF) and leprosy are disabling infectious diseases endemic in Nepal. LF infection can lead to lymphoedema and hydrocoele, while secondary effects of leprosy infection include impairments to hands, eyes and feet. The disabling effects of both conditions can be managed through self-care and the supportive effects of self-help groups (SHGs). A network of SHGs exists for people affected by leprosy in four districts in Nepal's Central Development Region, however no such service exists for people affected by LF. The aim of this study was to determine the feasibility of integrating LF affected people into existing leprosy SHGs in this area. METHODS: A survey was conducted using a semi-structured questionnaire to elicit information on: (i) participant characteristics, clinical manifestation and disease burden; (ii) participants' knowledge of management of their condition and access to services; and (iii) participants' knowledge and perceptions of the alternate condition (LF affected participants' knowledge of leprosy and vice versa) and attitudes towards integration. RESULTS: A total of 52 LF affected and 53 leprosy affected participants were interviewed from 14 SHGs. On average, leprosy affected participants were shown to have 1.8 times greater knowledge of self-care techniques, and practiced 2.5 times more frequently than LF affected participants. Only a quarter of LF affected participants had accessed a health service for their condition, compared with 94.3% of leprosy affected people accessing a service (including SHGs), at least once a week. High levels of stigma were perceived by both groups towards the alternate condition, however, the majority of LF (79%) and leprosy (94.3%) affected participants stated that they would consider attending an integrated SHG. CONCLUSIONS: LF affected participants need to increase their knowledge of self-care and access to health services. Despite stigma being a potential barrier, attitudes towards integration were positive, suggesting that the SHGs may be a good platform for LF affected people to start self-care in this area. TRIAL REGISTRATION: This is not a registered trial.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Prestação Integrada de Cuidados de Saúde , Filariose Linfática/terapia , Autocuidado , Grupos de Autoajuda/organização & administração , Filariose Linfática/psicologia , Estudos de Viabilidade , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Hanseníase/psicologia , Hanseníase/terapia , Masculino , Pessoa de Meia-Idade , Nepal , Estigma Social
7.
Ethiop Med J ; 55(Suppl 1): 45-54, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28878429

RESUMO

Lymphatic filariasis (LF) is one of the most debilitating and disfiguring diseases common in Ethiopia and is caused by Wuchereria bancrofti. Mapping for LF has shown that 70 woredas (districts) are endemic and 5.9 million people are estimated to be at risk. The national government's LF elimination programme commenced in 2009 in 5 districts integrated with the onchocerciasis programme. The programme developed gradually and has shown significant progress over the past 6 years, reaching 100% geographical coverage for mass drug administration (MDA) by 2016. To comply with the global LF elimination goals an integrated morbidity management and disability prevention (MMDP) guideline and a burden assessment programme has also been developed; MMDP protocols and a hydrocoele surgical handbook produced for country-wide use. In Ethiopia, almost all LF endemic districts are co-endemic with malaria and vector control aspects of the activities are conducted in the context of malaria programme as the vectors for both diseases are mosquitoes. In order to monitor the elimination, 11 sentinel and spot-check sites have been established and baseline information has been collected. Although significant achievements have been achieved in the scale up of the LF elimination programme, there is still a need to strengthen operational research to generate programme-relevant evidence, to increase access to morbidity management services, and to improve monitoring and evaluation of the LF programme. However, the current status of implementation of the LF national programme indicates that Ethiopia is poised to achieve the 2020 goal of elimination of LF. Nevertheless, to achieve this goal, high and sustained treatment coverage and strong monitoring and evaluation of the programme are essential.


Assuntos
Controle de Doenças Transmissíveis/métodos , Filariose Linfática/tratamento farmacológico , Filariose Linfática/prevenção & controle , Filaricidas/administração & dosagem , Programas Nacionais de Saúde/organização & administração , Wuchereria bancrofti/efeitos dos fármacos , Animais , Culicidae , Filariose Linfática/epidemiologia , Doenças Endêmicas , Etiópia/epidemiologia , Humanos , Insetos Vetores , Prevalência , Vigilância de Evento Sentinela , Resultado do Tratamento , Wuchereria bancrofti/isolamento & purificação
9.
Clin Infect Dis ; 61(4): 517-26, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25948064

RESUMO

BACKGROUND: Ivermectin (IVM) has been the drug of choice for the treatment of onchocerciasis. However, there have been reports of persistent microfilaridermia in individuals from an endemic area in Ghana after many rounds of IVM, raising concerns of suboptimal response or even the emergence of drug resistance. Because it is considered risky to continue relying only on IVM to combat this phenomenon, we assessed the effect of targeting the Onchocerca volvulus Wolbachia endosymbionts with doxycycline for these individuals with suboptimal response. METHODS: One hundred sixty-seven patients, most of them with multiple rounds of IVM, were recruited in areas with IVM suboptimal response and treated with 100 mg/day doxycycline for 6 weeks. Three and 12 months after doxycycline treatment, patients took part in standard IVM treatment. RESULTS: At 20 months after treatment, 80% of living female worms from the placebo group were Wolbachia positive, whereas only 5.1% in the doxycycline-treated group contained bacteria. Consistent with interruption of embryogenesis, none of the nodules removed from doxycycline-treated patients contained microfilariae, and 97% of those patients were without microfilaridermia, in contrast to placebo patients who remained at pretreatment levels (P < .001). Moreover, a significantly enhanced number of dead worms were observed after doxycycline. CONCLUSIONS: Targeting the Wolbachia in O. volvulus is effective in clearing microfilariae in the skin of onchocerciasis patients with persistent microfilaridermia and in enhanced killing of adult worms after repeated standard IVM treatment. Strategies can now be developed that include doxycycline to control onchocerciasis in areas where infections persist despite the frequent use of IVM. CLINICAL TRIALS REGISTRATION: ISRCTN 66649839.


Assuntos
Antibacterianos/administração & dosagem , Doxiciclina/administração & dosagem , Onchocerca volvulus/efeitos dos fármacos , Onchocerca volvulus/fisiologia , Oncocercose/tratamento farmacológico , Wolbachia/efeitos dos fármacos , Adolescente , Adulto , Animais , Método Duplo-Cego , Feminino , Filaricidas/administração & dosagem , Gana , Humanos , Ivermectina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Onchocerca volvulus/microbiologia , Placebos/administração & dosagem , Resultado do Tratamento , Adulto Jovem
10.
Int Health ; 16(2): 227-229, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-37183774

RESUMO

BACKGROUND: By 1987, onchocerciasis in Niger had been successfully controlled in the six endemic river basins. In 2017, onchocerciasis elimination mapping (OEM) was carried out to determine if there was any ongoing transmission in the country as a whole. METHODS: The recommended OEM procedures were implemented. RESULTS: Ten districts, that included 35 villages, required field investigation as sites of possible transmission. None of these were found capable of supporting black fly breeding, nor was there any evidence of the presence of Simulium sp. flies. CONCLUSIONS: The implementation of OEM indicates that there is no transmission of onchocerciasis currently taking place in these newly assessed sites in Niger.


Assuntos
Oncocercose , Simuliidae , Animais , Humanos , Oncocercose/epidemiologia , Oncocercose/prevenção & controle , Níger/epidemiologia , África Ocidental/epidemiologia , Ivermectina
11.
PLoS Negl Trop Dis ; 18(2): e0011957, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38363794

RESUMO

BACKGROUND: Lymphatic filariasis (LF) is a parasitic disease transmitted by mosquitoes, causing severe pain, disfiguring, and disabling clinical conditions such as lymphoedema and hydrocoele. LF is a global public health problem affecting 72 countries, primarily in Africa and Asia. Since 2000, the World Health Organization (WHO) has led the Global Programme to Eliminate Lymphatic Filariasis (GPELF) to support all endemic regions. This paper focuses on the achievements of the Malawi LF Elimination Programme between 2000 and 2020 to eliminate LF as a public health problem, making it the second sub-Saharan country to receive validation from the WHO. METHODOLOGY/PRINCIPAL FINDINGS: The Malawi LF Programme addressed the widespread prevalence of LF infection and disease across the country, using the recommended WHO GPELF strategies and operational research initiatives in collaboration with key national and international partners. First, to stop the spread of infection (i.e., interrupt transmission) and reduce the circulating filarial antigen prevalence from as high as 74.4% to below the critical threshold of 1-2% prevalence, mass drug administration (MDA) using a two-drug regime was implemented at high coverage rates (>65%) of the total population, with supplementary interventions from other programmes (e.g., malaria vector control). The decline in prevalence was monitored and confirmed over time using several impact assessment and post-treatment surveillance tools including the standard sentinel site, spot check, and transmission assessment surveys and alternative integrated, hotspot, and easy-access group surveys. Second, to alleviate suffering of the affected populations (i.e., control morbidity) the morbidity management and disability prevention (MMDP) package of care was implemented. Specifically, clinical case estimates were obtained via house-to-house patient searching activities; health personnel and patients were trained in self-care protocols for lymphoedema and/or referrals to hospitals for hydrocoele surgery; and the readiness and quality of treatment and services were assessed with new survey tools. CONCLUSIONS: Malawi's elimination of LF will ensure that future generations are not infected and suffer from the disfiguring and disabling disease. However, it will be critical that the Malawi LF Elimination programme remains vigilant, focussing on post-elimination surveillance and MMDP implementation and integration into routine health systems to support long-term sustainability and ongoing success. SUMMARY: Lymphatic filariasis, also known as elephantiasis, is a disabling, disfiguring, and painful disease caused by a parasite that infected mosquitoes transmit to millions of people worldwide. Since 2000, the Global Programme to Eliminate Lymphatic Filariasis (GPELF) has supported endemic countries such as Malawi in south-eastern Africa, to eliminate the disease as a public health problem. The Malawi National LF Elimination Programme has worked tirelessly over the past two decades to implement the GPELF recommended strategies to interrupt the transmission with a two-drug regime, and to alleviate suffering in patients with lymphoedema and/or hydrocoele through morbidity management and disability prevention. Additionally, the LF Programme has collaborated with national and international stakeholders to implement a range of supplementary operational research projects to address outstanding knowledge gaps and programmatic barriers. In 2020, the World Health Organisation validated that Malawi had successfully eliminated LF as a public health problem, making it the second country in sub-Saharan Africa to achieve this, which is remarkable given that Malawi previously had very high infection rates. The LF Programme now remains vigilant, putting its efforts towards post-elimination surveillance and the continued implementation of care for patients with chronic conditions. Malawi's elimination of LF will ensure that future generations are not affected by this devastating disease.


Assuntos
Anopheles , Filariose Linfática , Linfedema , Malária , Animais , Humanos , Filariose Linfática/tratamento farmacológico , Filariose Linfática/epidemiologia , Filariose Linfática/prevenção & controle , Saúde Pública , Malaui/epidemiologia , Mosquitos Vetores , Cegueira
12.
Proc Natl Acad Sci U S A ; 107(46): 20120-5, 2010 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-21041637

RESUMO

Ivermectin (IVM) is a broad-spectrum anthelmintic used in filariasis control programs. By binding to nematode glutamate-gated chloride channels (GluCls), IVM disrupts neurotransmission processes regulated by GluCl activity. IVM treatment of filarial infections is characterized by an initial dramatic drop in the levels of circulating microfilariae, followed by long-term suppression of their production, but the drug has little direct effect on microfilariae in culture at pharmacologically relevant concentrations. We localized Brugia malayi GluCl expression solely in a muscle structure that surrounds the microfilarial excretory-secretory (ES) vesicle, which suggests that protein release from the ES vesicle is regulated by GluCl activity. Consistent with this hypothesis, exposure to IVM in vitro decreased the amount of protein released from microfilariae. To better understand the scope of IVM effects on protein release by the parasite, three different expression patterns were identified from immunolocalization assays on a representative group of five microfilarial ES products. Patterns of expression suggest that the ES apparatus is the main source of regulated ES product release from microfilariae, as it is the only compartment that appears to be under neuromuscular control. Our results show that IVM treatment of microfilariae results in a marked reduction of protein release from the ES apparatus. Under in vivo conditions, the rapid microfilarial clearance induced by IVM treatment is proposed to result from suppression of the ability of the parasite to secrete proteins that enable evasion of the host immune system.


Assuntos
Estruturas Animais/efeitos dos fármacos , Estruturas Animais/metabolismo , Anti-Helmínticos/farmacologia , Brugia Malayi/anatomia & histologia , Brugia Malayi/efeitos dos fármacos , Ivermectina/farmacologia , Microfilárias/anatomia & histologia , Microfilárias/efeitos dos fármacos , Animais , Brugia Malayi/citologia , Canais de Cloreto/metabolismo , Clonagem Molecular , Proteínas de Helminto/metabolismo , Microfilárias/citologia , Dados de Sequência Molecular , Músculos/efeitos dos fármacos , Músculos/metabolismo , Filogenia , Subunidades Proteicas , Receptores de Droga/metabolismo
14.
PLoS Negl Trop Dis ; 17(7): e0011348, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37440479

RESUMO

Understanding when it is the appropriate time to stop administering the drugs in a chemotherapy-centered treatment program such as onchocerciasis remains a challenge due to cost, imperfect testing procedures, and a lack of long-term experience. Different approaches for assessing when a program can begin the extensive stop-treatment surveys have been recommended, and tested, with varying results. We describe here a practical approach that is based on information on both transmission as well as infection. This new protocol first defines operational transmission zones (OTZs) based on vector breeding sites followed by an epidemiological assessment of the resident populations adjacent to these breeding sites. Basing decisions to stop MDA treatment based on breeding site locations (i.e., transmission zones) rather than on political administrative units, is a practical, cost-effective approach. Importantly, this biology-based approach is more closely related to the actual state of onchocerciasis transmission.


Assuntos
Oncocercose , Humanos , Oncocercose/tratamento farmacológico , Oncocercose/epidemiologia , Oncocercose/prevenção & controle , Administração Massiva de Medicamentos , Ivermectina/uso terapêutico , Análise de Custo-Efetividade , Instalações de Saúde
15.
PLoS Negl Trop Dis ; 17(12): e0011815, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38096317

RESUMO

BACKGROUND: Onchocerca volvulus is a filarial parasite that is a major cause of dermatitis and blindness in endemic regions primarily in sub-Saharan Africa. Widespread efforts to control the disease caused by O. volvulus infection (onchocerciasis) began in 1974 and in recent years, following successful elimination of transmission in much of the Americas, the focus of efforts in Africa has moved from control to the more challenging goal of elimination of transmission in all endemic countries. Mass drug administration (MDA) with ivermectin has reached more than 150 million people and elimination of transmission has been confirmed in four South American countries, with at least two African countries having now stopped MDA as they approach verification of elimination. It is essential that accurate data for active transmission are used to assist in making the critical decision to stop MDA, since missing low levels of transmission and infection can lead to continued spread or recrudescence of the disease. METHODOLOGY/PRINCIPAL FINDINGS: Current World Health Organization guidelines for MDA stopping decisions and post-treatment surveillance include screening pools of the Simulium blackfly vector for the presence of O. volvulus larvae using a PCR-ELISA-based molecular technique. In this study, we address the potential of an updated, practical, standardized molecular diagnostic tool with increased sensitivity and species-specificity by comparing several candidate qPCR assays. When paired with heat-stable reagents, a qPCR assay with a mitochondrial DNA target (OvND5) was found to be more sensitive and species-specific than an O150 qPCR, which targets a non-protein coding repetitive DNA sequence. The OvND5 assay detected 19/20 pools of 100 blackfly heads spiked with a single L3, compared to 16/20 for the O150 qPCR assay. CONCLUSIONS/SIGNIFICANCE: Given the improved sensitivity, species-specificity and resistance to PCR inhibitors, we identified OvND5 as the optimal target for field sample detection. All reagents for this assay can be shipped at room temperature with no loss of activity. The qPCR protocol we propose is also simpler, faster, and more cost-effective than the current end-point molecular assays.


Assuntos
Volvo Intestinal , Onchocerca volvulus , Oncocercose , Simuliidae , Animais , Humanos , DNA Mitocondrial , Ivermectina/uso terapêutico , Onchocerca/genética , Onchocerca volvulus/genética , Oncocercose/tratamento farmacológico , Simuliidae/parasitologia
16.
PLoS Negl Trop Dis ; 17(11): e0011632, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37967137

RESUMO

BACKGROUND: Onchocerciasis control activities in Mali began in 1975 with vector larviciding carried out by the Onchocerciasis Control Programme (OCP), followed by the distribution of ivermectin from 1998 until the closure of the OCP in 2002. At that time, epidemiological evaluations, using skin snip microscopy and O-150 pool screening PCR in black flies, indicated that the disease had been largely controlled as a public health problem. Ivermectin distribution was nevertheless continued after 2002 in 34 of the 75 health districts in Mali as these were known to still be meso- or hyper-endemic for onchocerciasis. In addition, the onchocerciasis sites known to be hypo-endemic for onchocerciasis benefited from the distribution of ivermectin treatment as part of the mass drug administration (MDA) program for lymphatic filariasis. Various entomological and epidemiological evaluations have now indicated that Mali may have achieved successful interruption of onchocerciasis transmission. METHODS: A series of cross-sectional surveys to update vector breeding sites throughout the endemic areas, followed by a pre-stop ivermectin mass drug administration (Pre-stop MDA) survey, were undertaken in 2019-2020. Based on breeding site findings, historical epidemiological assessments, and vector collection site maps, 18 operational transmission zones (OTZ) were delineated within which a total of 104 first line villages were selected for evaluation. Dried blood spots (DBS) samples were collected from 10,400 children (5-9 years old) from these 104 first line villages and processed for the presence of OV16 antibody using a lab-based rapid diagnostic test. RESULTS: Within the 544 Simulium damnosum s.l. breeding sites visited in all five endemic onchocerciasis endemic regions of Mali 18.01% (98/544) were seen to be active with the presence of at least one stage of S. damnosum. The overall prevalence of OV16 positive children was 0.45% (47/10,400). However, two hotspots were identified: 2.60% (13/500) seroprevalence in the OTZ number 5 in Kayes Region and 1.40% (7/500) in the OTZ number 1 of Sikasso Region. CONCLUSION: These data show that onchocerciasis prevalence in the five endemic regions has declined to levels that indicate that Stop-MDA surveys should be now carried out in most of the OTZ except for one in the Kayes Region. This latter site will need additional ivermectin treatment before reevaluation, and an OTZ in the Sikasso Region requires revaluation before possibly reinitiating MDA.


Assuntos
Oncocercose , Simuliidae , Criança , Animais , Humanos , Pré-Escolar , Oncocercose/tratamento farmacológico , Oncocercose/epidemiologia , Oncocercose/prevenção & controle , Ivermectina/uso terapêutico , Administração Massiva de Medicamentos , Mali/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais
17.
Infect Dis Poverty ; 11(1): 9, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042539

RESUMO

BACKGROUND: Lymphatic filariasis (LF) remains one of the world's most debilitating parasitic infections and is a major contributor to poor health in many endemic countries. The provision of continuing care for all those affected by LF and its consequences is an important component of the United Nations' Sustainable Development Goals. The aim of this study is to integrate lymphedema care into the primary health care system of the State by developing lymphedema clinics at each district, through training of health personnel to fulfill WHO recommendation for morbidity management and disability prevention. METHODS: Selected health care providers from all the districts in Kerala State of India participated in intensive training sessions endorsed by the State's health administration. The six training sessions (from 5 June 2017 to 25 May 2018) included appropriate self-care information and development of individual plans for each participating institution to provide instruction and care for their lymphoedema patients. The learning achieved by attendees was assessed by pre- and post-training tests. The number of lymphoedema patients receiving care and instruction from the post-training activities of each participating institution was assessed from local records, 6 months after the conclusion of the training sessions. RESULTS: One hundred and eighty-four medical personnel (91 doctors and 93 nurses) from 82 medical institutions were trained which quickly led to the establishment of active lymphoedema clinics providing the essential package of care (EPC) for lymphoedema patients at all the participating institutions. Six months after the training sessions the number of previously unidentified lymphoedema patients registered and receiving care at these clinics ranged from 296 to almost 400 per clinic, with a total of 3,477 new patients receiving training in EPC. CONCLUSIONS: Generalist health personnel, when appropriately trained, can provide quality lymphoedema care in public health settings and patients when provided services close to their home, are willing to access them. This is a feasible strategy for integrating long term care for LF patients into the national health system, and is a clear example of moving towards equity in health care for the medically underserved, and thus successfully addresses a major goal of the global program to eliminate lymphatic filariasis.


Assuntos
Filariose Linfática , Linfedema , Atenção à Saúde , Filariose Linfática/epidemiologia , Filariose Linfática/terapia , Serviços de Saúde , Humanos , Índia , Linfedema/terapia
18.
J Feline Med Surg ; 24(2): 123-130, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33908303

RESUMO

OBJECTIVES: Malodors stemming from soiled cat litter are a major frustration for cat owners, despite the widespread use of absorbent litters with claims of odor control. Technologies for effective litter odor control have not been rigorously evaluated. Here, we report on the effectiveness of a novel litter formulation of 1-monochlorodimethylhydantoin (MCDMH)-modified clinoptilolite zeolite (MCDMH-Z) to control the odors of 3-mercapto-3-methylbutanol (3M3MB) and ammonia, the principal products generated by the enzymatic breakdown of felinine and urea, respectively. METHODS: The efficacy of MCDMH-Z for the odor control of 3M3MB was determined by solid-phase microextraction and gas chromatography mass spectrometry analysis, colorimetric analysis and a sensory panel. Enzyme inhibition was monitored by a colorimetric coupled assay for ammonia. The antimicrobial properties were measured by a reduction in colony-forming units (CFUs). RESULTS: 3M3MB proved highly susceptible to modification by MCDMH-Z granules. Headspace above litter exposed to MCDMH-Z showed no detectable 3M3MB; levels >59 ng were detected in commercially available products. Urease activity decreased by >97% after incubation with MCDMH-Z to 0.14 mg/ml. Cat litter F showed comparable inhibition (0.13 mg/ml); others showed less inhibition, producing up to 4.8 mg/ml of ammonia. MCDMH-Z reduced the CFUs of Proteus vulgaris by six log reduction values in 30 mins; in the same amount of time, no reduction was seen with commercial products tested. The odor control capability of the MCDMH-Z granules was further supported by a sensory panel scoring 3M3MB-spiked litters. CONCLUSIONS AND RELEVANCE: Samples of commercially available litter products showed an effect on malodor, or inhibition of urease, or contained antimicrobial activity; no samples were capable of accomplishing these concurrently. In contrast, MCDMH-Z granules were effective in all three test categories. Control of felinine-derived odors, in particular, has the potential to improve cat owner satisfaction, and may beneficially affect cat behaviors provoked by pheromonally active sulfurous metabolites deposited in the litter.


Assuntos
Anti-Infecciosos , Odorantes , Animais , Gatos , Cisteína/análogos & derivados , Cisteína/análise , Cisteína/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Odorantes/análise
19.
Int Health ; 14(Suppl 1): i17-i23, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35169850

RESUMO

BACKGROUND: Onchocerciasis is targeted for elimination of transmission by 2030 in at least 21 countries. To achieve this, recent and accurate data on the extent and intensity of onchocerciasis transmission are required. This will include mapping areas previously unassessed, or remapping of areas that were last visited as part surveys aiming to prevent blindness, not assess transmission in totality. There is near universal acceptance of the need to carry out these mapping reassessments, to achieve equitable and lasting elimination of onchocerciasis transmission. However, there is no consensus on how to conduct onchocerciasis elimination mapping (OEM), and little published data to inform policymakers and programme managers, including on cost. METHODS: Here, we summarise the methods and cost implications of conducting pilot OEM surveys in Ghana and Nigeria in 2018. We have included a breakdown of costs incurred overall, per person and per implementation unit in each country, as well as detailed analysis of the cost categories and the main cost drivers. RESULTS: The procurement and logistics of diagnostics accounted for more than one-third of the total cost, a significant cost driver. CONCLUSIONS: This information will be valuable to policymakers and donors as they seek to prioritise onchocerciasis elimination and plan to complete OEM.


Assuntos
Oncocercose , Custos e Análise de Custo , Erradicação de Doenças/métodos , Estudos de Viabilidade , Humanos , Ivermectina/uso terapêutico , Oncocercose/prevenção & controle
20.
Am J Trop Med Hyg ; 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35226875

RESUMO

Dracunculus medinensis (Guinea worm [GW]), a zoonotic nematode targeted for eradication, has been managed using interventions aimed at humans; however, increases in domestic dog GW infections highlight the need for novel approaches. We conducted two clinical trials evaluating the efficacy of subcutaneously injected flubendazole (FBZ) as a treatment of GW infection. The first trial was conducted administering FBZ to experimentally infected ferrets; the second trial involved administering FBZ or a placebo to domestic dogs in the Republic of Tchad (Chad). We found contrasting results between the two trials. When adult gravid female GW were recovered from ferrets treated with FBZ, larvae presented in poor condition, with low to no motility, and an inability to infect copepods. Histopathology results indicated a disruption to morulae development within uteri of worms from treated animals. Results from the trial in Chadian dogs failed to indicate significant treatment of or prevention against GW infection. However, the difference in treatment intervals (1 month for ferrets and 6 months for dogs) or the timing of treatment (ferrets were treated later in the GW life-cycle than dogs) could explain different responses to the subcutaneous FBZ injections. Both trials provided valuable data guiding the use of FBZ in future trials (such as decreasing treatment intervals or increasing the dose of FBZ in dogs to increase exposure), and highlighted important lessons learned during the implementation of a field-based, double-blinded randomized control trial in Chadian dogs.

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