RESUMO
OBJECTIVE: To differentiate exposure to the newly introduced chikungunya virus from exposure to endemic dengue virus and other pathogens in Haiti. METHODS: We used a multiplex bead assay to detect immunoglobulin G (IgG) responses to a recombinant chikungunya virus antigen, two dengue virus-like particles and three recombinant Plasmodium falciparum antigens. Most (217) of the blood samples investigated were collected longitudinally, from each of 61 children, between 2011 and 2014 but another 127 were collected from a cross-sectional sample of children in 2014. FINDINGS: Of the samples from the longitudinal cohort, none of the 153 collected between 2011 and 2013 but 78.7% (48/61) of those collected in 2014 were positive for IgG responses to the chikungunya virus antigen. In the cross-sectional sample, such responses were detected in 96 (75.6%) of the children and occurred at similar prevalence across all age groups. In the same sample, responses to malarial antigen were only detected in eight children (6.3%) but the prevalence of IgG responses to dengue virus antigens was 60.6% (77/127) overall and increased steadily with age. Spatial analysis indicated that the prevalence of IgG responses to the chikungunya virus and one of the dengue virus-like particles decreased as the sampling site moved away from the city of Léogâne and towards the ocean. CONCLUSION: Serological evidence indicates that there had been a rapid and intense dissemination of chikungunya virus in Haiti. The multiplex bead assay appears to be an appropriate serological platform to monitor the seroprevalence of multiple pathogens simultaneously.
Assuntos
Febre de Chikungunya , Dengue , Exposição Ambiental , Malária , Adolescente , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/isolamento & purificação , Criança , Pré-Escolar , Estudos Transversais , Dengue/diagnóstico , Dengue/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Feminino , Haiti/epidemiologia , Humanos , Estudos Longitudinais , Malária/diagnóstico , Malária/epidemiologia , Masculino , Plasmodium falciparum/isolamento & purificaçãoRESUMO
Support groups can create environments that are conducive to healing and well-being, particularly for persons with stigmatizing chronic diseases. In 1998, the support group concept was adapted in Haiti for persons with disabling lymphedema caused by lymphatic filariasis (LF). The project was developed with the expectation that the support group model conceived in the developed world be interpreted and modified by persons affected with lymphedema in the Haitian setting. Initiated with modest financial support within a research initiative to eliminate LF, a total of 50 "Hope Clubs" were formed from 1998 to 2023 across seven communes (districts) located in 3 of Haiti's 10 regional Departments. Documented benefits of the support groups included improved limb self-care, decreased incidence of inflammatory episodes (adenolymphangitis), enhanced self-efficacy, economic benefit through microenterprise, and improved quality of life. Despite challenges of funding shortfalls, natural disasters, and political insecurity, persistence of LF support groups in Haiti highlights the crucial role of group ownership by affected persons and the freedom to reinvent the support group concept in light of local social, cultural, and economic conditions.
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BACKGROUND: Microsatellite markers have proven useful in genetic studies in many organisms, yet microsatellite-based studies of the dengue and yellow fever vector mosquito Aedes aegypti have been limited by the number of assayable and polymorphic loci available, despite multiple independent efforts to identify them. Here we present strategies for efficient identification and development of useful microsatellites with broad coverage across the Aedes aegypti genome, development of multiplex-ready PCR groups of microsatellite loci, and validation of their utility for population analysis with field collections from Haiti. RESULTS: From 79 putative microsatellite loci representing 31 motifs identified in 42 whole genome sequence supercontig assemblies in the Aedes aegypti genome, 33 microsatellites providing genome-wide coverage amplified as single copy sequences in four lab strains, with a range of 2-6 alleles per locus. The tri-nucleotide motifs represented the majority (51%) of the polymorphic single copy loci, and none of these was located within a putative open reading frame. Seven groups of 4-5 microsatellite loci each were developed for multiplex-ready PCR. Four multiplex-ready groups were used to investigate population genetics of Aedes aegypti populations sampled in Haiti. Of the 23 loci represented in these groups, 20 were polymorphic with a range of 3-24 alleles per locus (mean = 8.75). Allelic polymorphic information content varied from 0.171 to 0.867 (mean = 0.545). Most loci met Hardy-Weinberg expectations across populations and pairwise FST comparisons identified significant genetic differentiation between some populations. No evidence for genetic isolation by distance was observed. CONCLUSION: Despite limited success in previous reports, we demonstrate that the Aedes aegypti genome is well-populated with single copy, polymorphic microsatellite loci that can be uncovered using the strategy developed here for rapid and efficient screening of genome supercontig assemblies. These loci are suitable for genetic and population studies using multiplex-PCR.
Assuntos
Aedes/química , Genoma de Inseto , Repetições de Microssatélites , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Aedes/genética , Animais , Dosagem de Genes , Genética Populacional , HaitiRESUMO
Research provides the essential foundation of disease elimination programs, including the global program to eliminate lymphatic filariasis (GPELF). The development and validation of new diagnostic tools and intervention strategies, critical steps in the evolution of GPELF, required a global effort. Lymphatic filariasis research in Haiti involved many partners and was directly linked to the development of the national elimination program and to the success achieved to date. Ongoing research efforts involving many partners will continue to be important in resolving the challenges faced by the program today in its final efforts to achieve elimination.
Assuntos
Erradicação de Doenças , Filariose Linfática/prevenção & controle , Linfedema/terapia , Dietilcarbamazina/uso terapêutico , Filariose Linfática/complicações , Filariose Linfática/tratamento farmacológico , Filaricidas/uso terapêutico , Haiti , Humanos , Linfedema/etiologiaRESUMO
BACKGROUND: Since 2001, Haiti's National Program for the Elimination of Lymphatic Filariasis (NPELF) has worked to reduce the transmission of lymphatic filariasis (LF) through annual mass drug administration (MDA) with diethylcarbamazine and albendazole. The NPELF reached full national coverage with MDA for LF in 2012, and by 2014, a total of 14 evaluation units (48 communes) had met WHO eligibility criteria to conduct LF transmission assessment surveys (TAS) to determine whether prevalence had been reduced to below a threshold, such that transmission is assumed to be no longer sustainable. Haiti is also endemic for malaria and many communities suffer a high burden of soil transmitted helminths (STH). Heeding the call from WHO for integration of neglected tropical diseases (NTD) activities, Haiti's NPELF worked with the national malaria control program (NMCP) and with partners to develop an integrated TAS (LF-STH-malaria) to include assessments for malaria and STH. METHODOLOGY/PRINCIPLE FINDINGS: The aim of this study was to evaluate the feasibility of using TAS surveys for LF as a platform to collect information about STH and malaria. Between November 2014 and June 2015, TAS were conducted in 14 evaluation units (EUs) including 1 TAS (LF-only), 1 TAS-STH-malaria, and 12 TAS-malaria, with a total of 16,655 children tested for LF, 14,795 tested for malaria, and 298 tested for STH. In all, 12 of the 14 EUs passed the LF TAS, allowing the program to stop MDA for LF in 44 communes. The EU where children were also tested for STH will require annual school-based treatment with albendazole to maintain reduced STH levels. Finally, only 12 of 14,795 children tested positive for malaria by RDT in 38 communes. CONCLUSIONS/SIGNIFICANCE: Haiti's 2014-2015 Integrated TAS surveys provide evidence of the feasibility of using the LF TAS as a platform for integration of assessments for STH and or malaria.
Assuntos
Filariose Linfática/transmissão , Helmintos/isolamento & purificação , Malária/transmissão , Solo/parasitologia , Animais , Criança , Filariose Linfática/epidemiologia , Filariose Linfática/parasitologia , Feminino , Haiti/epidemiologia , Helmintos/classificação , Helmintos/genética , Humanos , Malária/epidemiologia , Malária/parasitologia , MasculinoRESUMO
To support the global program to eliminate lymphatic filariasis (LF), well-monitored demonstration projects are important for defining the relationship between coverage and reductions in microfilaremia. We are using mass treatment with diethylcarbamazine (DEC) and albendazole in an effort to eliminate LF from Leogane, Haiti. Wuchereria bancrofti microfilaremia prevalence at baseline ranged from 0.8% to 15.9% in four sentinel sites. After three rounds of DEC-albendazole mass drug administration (MDA), both microfilaremia prevalence and intensity decreased dramatically. Mild and moderate adverse reactions after treatment were common, especially after the first MDA, but decreased after subsequent MDAs. Drug coverage for the first year was estimated to be 72%, but concerns about adverse reactions appeared to decrease drug coverage in the second MDA. As a result of community education efforts that focused on providing a greater understanding of adverse reactions, coverage increased dramatically for the third round. Program efficiency increased substantially; the costs per person treated for three rounds of MDA were 2.23 US dollars, 1.96 US dollars, and 1.30 US dollars per person, respectively. The Leogane experience highlights the importance of adapting community education and mobilization campaigns to achieve and maintain good coverage.
Assuntos
Albendazol/administração & dosagem , Dietilcarbamazina/administração & dosagem , Filaricidas/administração & dosagem , Avaliação de Programas e Projetos de Saúde , Albendazol/economia , Albendazol/uso terapêutico , Animais , Dietilcarbamazina/economia , Dietilcarbamazina/uso terapêutico , Quimioterapia Combinada , Filariose Linfática/tratamento farmacológico , Filariose Linfática/economia , Filariose Linfática/epidemiologia , Filariose Linfática/prevenção & controle , Filaricidas/economia , Filaricidas/uso terapêutico , Programas Governamentais/economia , Haiti , Educação em Saúde , Humanos , Microfilárias/efeitos dos fármacos , Microfilárias/crescimento & desenvolvimento , Vigilância de Evento Sentinela , Wuchereria bancrofti/efeitos dos fármacosRESUMO
Both secondary infections and antifilarial immunity are thought to play roles in the development and progression of lymphedema. To investigate this issue, immune responses to a panel of bacterial, fungal, and parasite antigens were examined for women with lymphedema and elephantiasis (n = 28) and for women with no clinical evidence of lymphatic dysfunction who were either microfilaremic (Mf+, n = 23) or microfilaria- and filarial antigen-negative (Ag-, n = 24). The prevalence and intensity of delayed-type hypersensitivity (DTH) responses was similar for most recall antigens; for individual antigens, lymphedema patients were significantly more likely to be reactive only to Proteus. Lymphedema patients with a history of three or more attacks of adenolymphangitis in the last 18 months showed increased DTH reactivity to Trichophyton. Proliferative responses to fungal and bacterial antigens were similar for all three groups; however, antigen-negative women, independent of disease status, mounted greater responses to filarial antigen. In contrast, lymphedema patients had higher levels of antifilarial specific IgG1, IgG2, and IgG3 and higher IgG responses to streptolysin O than either Ag- or Mf+ women. In persons with lymphatic filariasis, immune reactivity is influenced by disease status as well as infection status.
Assuntos
Antígenos , Filariose Linfática/imunologia , Hipersensibilidade Tardia/epidemiologia , Leucócitos Mononucleares/imunologia , Linfedema/imunologia , Adolescente , Adulto , Idoso , Antígenos de Bactérias , Antígenos de Fungos , Antígenos de Helmintos , Criança , Progressão da Doença , Filariose Linfática/patologia , Feminino , Haiti/epidemiologia , Humanos , Hipersensibilidade Tardia/diagnóstico , Linfedema/patologia , Pessoa de Meia-Idade , Prevalência , Testes CutâneosRESUMO
Annual mass treatment with antifilarial drugs is the cornerstone of the global program to eliminate lymphatic filariasis (LF). Although the primary goal of the program is to interrupt transmission of LF, additional public health benefits also are expected because of the known anthelminthic properties of these drugs. Since rapid re-infection with intestinal helminths occurs following treatment, annual de-worming may not be sufficient to produce a lasting reduction in the prevalence and intensity of these infections. We conducted stool examinations in four sentinel communities before and approximately nine months after each of two rounds of mass drug administration (MDA) with diethylcarbamazine and albendazole in the context of an LF elimination program in Leogane, Haiti. At baseline, overall Ascaris, Trichuris, and hookworm infection prevalences were 20.9%, 34.0%, and 11.2%, respectively (n = 2,716 stools). Nine months after the second MDA, Ascaris, Trichuris and hookworm prevalences had decreased significantly, to 14.1%, 14.6%, and 2.0%, respectively (n = 814 stools). Infection intensity decreased significantly for all three parasites as well. These results demonstrate that substantial reductions in intestinal helminth infections are associated with mass treatment of filariasis in Haiti and are consistent with the conclusion that high levels of coverage for the LF program can decrease transmission of geohelminths.
Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Dietilcarbamazina/uso terapêutico , Filariose Linfática/tratamento farmacológico , Enteropatias Parasitárias/tratamento farmacológico , Nematoides/efeitos dos fármacos , Adolescente , Adulto , Distribuição por Idade , Albendazol/administração & dosagem , Animais , Anti-Helmínticos/administração & dosagem , Criança , Pré-Escolar , Dietilcarbamazina/administração & dosagem , Filariose Linfática/epidemiologia , Filariose Linfática/prevenção & controle , Fezes/parasitologia , Feminino , Humanos , Lactente , Recém-Nascido , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Prevalência , Vigilância de Evento SentinelaRESUMO
Although lymphatic filariasis is known to have been endemic in Haiti since at least the mid 1700s, a national filariasis survey has never been conducted. As a first step in the national program to eliminate filariasis, we collected blood in January-April 2001 from 50-250 school children (6-11 years old) in all 133 communes of the country using an adaptation of the lot quality assurance sampling method. Of 22,365 children tested, 901 (4.0%) were positive for circulating Wuchereria bancrofti antigen. When weighted by commune population, the overall national antigen prevalence in this age group was 7.3%. Infected children were found in 117 (87.9%) communes, the most heavily affected areas being concentrated in the northern part of the country. In only 16 (12.1%) communes were all 250 children antigen negative. Thus, W. bancrofti infection in Haiti is much more widespread than previously realized; virtually the entire population of the country may be considered at risk of infection.
Assuntos
Filariose Linfática/epidemiologia , Wuchereria bancrofti/isolamento & purificação , Animais , Antígenos de Helmintos/sangue , Criança , Filariose Linfática/sangue , Filariose Linfática/etiologia , Feminino , Geografia , Haiti/epidemiologia , Humanos , Masculino , Prevalência , Fatores de Risco , Wuchereria bancrofti/imunologiaRESUMO
BACKGROUND: Entomological methods may provide important tools for monitoring the progress of lymphatic filariasis elimination programs. In this study, we compared dissection of the vector, Culex quinquefasciatus, with the polymerase chain reaction (PCR) to assess filarial infection levels in mosquitoes in the context of a lymphatic filariasis elimination program in Leogane, Haiti. METHODS: Mosquitoes were collected using gravid traps located in 4 sentinel communities with Wuchereria bancrofti microfilaria prevalence that ranged from 0.8% to 15.9%. Captured mosquitoes were divided between dissection, to enumerate W. bancrofti larvae (L1, L2, L3) and desiccation for later analysis by PCR. PCR was conducted on DNA extracts from pooled mosquitoes (1-15 pooled females) utilizing a competitive PCR system with primers specific for the Ssp I repeat. PCR products were analyzed with a hybridization ELISA using probes specific for a control sequence and the Ssp I repeat. RESULTS: The prevalence of mosquito infection with W. bancrofti ranged from 0%-3.66% by dissection (L1-L3) and point estimates of infection prevalence, as assayed by PCR, ranged from 0.25% - 9.16%. Following mass treatment, W. bancrofti infection prevalence dropped significantly as determined by PCR and dissection in 2 of the 4 sentinel sites (Leogane and Barrier Jeudi, P = 0.04 and P = 0.005, respectively). Although transmission declined in the other two sites, larval recoveries were low and these changes were not statistically significant. DISCUSSION: Our results suggest that a single round of mass treatment can have an impact on transmission of lymphatic filariasis. The use of entomologic methods as a tool to monitor filariasis programs and the statistical limitations of mosquito trapping are discussed.
RESUMO
BACKGROUND: In the global program for the elimination of lymphatic filariasis (LF) longitudinal assessment of the prevalence of microfilaremia and antigenemia is recommended to monitor the effect of mass treatment on transmission. Additional monitoring tools such as entomologic and antibody methods may be useful in identifying residual foci of infection. In this study, we characterized serologic markers of infection and exposure spatially both before and after mass treatment, in an area of initial low Wuchereria bancrofti infection prevalence. METHODS: Consenting persons in the sentinel community were tested for circulating microfilaria and antigen (by immunochromatographic test) before and after the 1st annual mass drug administration of diethylcarbamazine and albendazole. A cohort of 161 persons provided serum specimens both years that were tested for antifilarial IgG (1 and 4) antibody. Every house was mapped using a differential Global Positioning System; this information was linked to the serologic data. W. bancrofti infection in the mosquito vector was assessed with year-round collection. Multiple linear regression was used to investigate the influence of antigen-positive persons on the antifilarial antibody responses of antigen-negative neighbors. RESULTS: After mass treatment, decreases were observed in the sentinel site in the overall prevalence of antigen (10.4% to 6.3%) and microfilaremia (0.9 to 0.4%). Of the persons in the cohort that provided serum specimens both years, 79% received treatment. Antigen prevalence decreased from 15.0% to 8.7%. Among 126 persons who received treatment, antigen and antifilarial IgG1 prevalence decreased significantly (p = 0.002 and 0.001, respectively). Among 34 persons who did not receive treatment, antifilarial IgG1 prevalence increased significantly (p = 0.003). Average antifilarial IgG1 levels decreased in households with high treatment coverage and increased in households that refused treatment. Each 10-meter increase in distance from the residence of a person who was antigen-positive in 2000 was associated a 4.68 unit decrease in antifilarial IgG1 level in 2001, controlling for other factors (p = 0.04). DISCUSSION: Antifilarial antibody assays can be used as a measure of filarial exposure. Our results suggest that micro-scale spatial heterogeneity exists in LF exposure and infection. Treatment appeared to be associated with reduced exposure at the sub-community level, suggesting the need to achieve high and homogeneous coverage. Public health messages should note the benefits of having one's neighbors receive treatment with antifilarial drugs.
RESUMO
We conducted a longitudinal analysis of 117 lymphedema patients in a filariasis-endemic area of Haiti during 1995-2008. No difference in lymphedema progression between those who received or did not receive mass drug administration (MDA) was found on measures of foot (P = 0.24), ankle (P = 0.87), or leg (P = 0.46) circumference; leg volume displacement (P = 0.09), lymphedema stage (P = 0.93), or frequency of adenolymphangitis (ADL) episodes (P = 0.57). Rates of ADL per year were greater after initiation of MDA among both groups (P < 0.01). Nevertheless, patients who received MDA reported improvement in four areas of lymphedema-related quality of life (P ≤ 0.01). Decreases in foot and ankle circumference and ADL episodes were observed during the 1995-1998 lymphedema management study (P ≤ 0.01). This study represents the first longitudinal, quantitative, leg-specific analysis examining the clinical effect of diethylcarbamazine on lymphedema progression and ADL episodes.
Assuntos
Albendazol/uso terapêutico , Dietilcarbamazina/uso terapêutico , Filariose Linfática/tratamento farmacológico , Inflamação/patologia , Ivermectina/uso terapêutico , Adolescente , Adulto , Idoso , Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/uso terapêutico , Criança , Dietilcarbamazina/administração & dosagem , Filariose Linfática/epidemiologia , Filariose Linfática/patologia , Feminino , Haiti/epidemiologia , Humanos , Ivermectina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Albendazole (ABZ), a benzimidazole (BZ) anthelmintic (AH), is commonly used for treatment of soil-transmitted helminths (STHs). Its regular use increases the possibility that BZ resistance may develop, which, in veterinary nematodes is caused by single nucleotide polymorphisms (SNPs) in the ß-tubulin gene at positions 200, 167 or 198. The relative importance of these SNPs varies among the different parasitic nematodes of animals studied to date, and it is currently unknown whether any of these are influencing BZ efficacy against STHs in humans. We assessed ABZ efficacy and SNP frequencies before and after treatment of Ascaris lumbricoides, Trichuris trichiura and hookworm infections. METHODS: Studies were performed in Haiti, Kenya, and Panama. Stool samples were examined prior to ABZ treatment and two weeks (Haiti), one week (Kenya) and three weeks (Panama) after treatment to determine egg reduction rate (ERR). Eggs were genotyped and frequencies of each SNP assessed. FINDINGS: In T. trichiura, polymorphism was detected at codon 200. Following treatment, there was a significant increase, from 3.1% to 55.3%, of homozygous resistance-type in Haiti, and from 51.3% to 67.8% in Kenya (ERRs were 49.7% and 10.1%, respectively). In A. lumbricoides, a SNP at position 167 was identified at high frequency, both before and after treatment, but ABZ efficacy remained high. In hookworms from Kenya we identified the resistance-associated SNP at position 200 at low frequency before and after treatment while ERR values indicated good drug efficacy. CONCLUSION: Albendazole was effective for A. lumbricoides and hookworms. However, ABZ exerts a selection pressure on the ß-tubulin gene at position 200 in T. trichiura, possibly explaining only moderate ABZ efficacy against this parasite. In A. lumbricoides, the codon 167 polymorphism seemed not to affect drug efficacy whilst the polymorphism at codon 200 in hookworms was at such low frequency that conclusions cannot be drawn.
Assuntos
Albendazol/uso terapêutico , Ancylostomatoidea/genética , Anti-Helmínticos/uso terapêutico , Ascaris lumbricoides/genética , Infecções por Nematoides/tratamento farmacológico , Trichuris/genética , Tubulina (Proteína)/genética , Adolescente , Ancylostomatoidea/isolamento & purificação , Animais , Ascaris lumbricoides/isolamento & purificação , Criança , Pré-Escolar , Estudos Transversais , Resistência a Medicamentos , Genótipo , Haiti , Humanos , Lactente , Quênia , Masculino , Infecções por Nematoides/parasitologia , Panamá , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Trichuris/isolamento & purificaçãoRESUMO
Antifilarial antibody testing has been established as a sensitive and specific method of diagnosing lymphatic filariasis. However, the development of serological responses to specific filarial antigens and their relationship to acquisition of infection is poorly understood. In order to evaluate whether the development of antigen specific antifilarial antibodies precedes microfilaremia and antigenemia, we compared the antibody responses of serum samples collected between 1990 and 1999 from a cohort of 142 Haitian children followed longitudinally. Antigen status was determined using the Og4C3 ELISA and the presence of microfilaremia was detected using microscopy. Antibody responses to Wb123, a Wuchereria bancrofti L3 antigen, were measured using a Luciferase Immunoprecipitation System (LIPS) assay. Antibody responses to Bm14 and Bm33, Brugia malayi antigens and to a major surface protein (WSP) from Wolbachia were analyzed using a multiplex bead assay. Over follow-up, 80 (56%) of the children became antigen-positive and 30 (21%) developed microfilaremia. Detectable antibody responses to Bm14, Bm33, Wb123, and WSP developed in 95%, 100%, 92%, and 29% of children, respectively. With the exception of WSP, the development of antibody responses generally preceded detection of filarial antigen. Our results show that antifilarial antibody responses can serve as an important epidemiological indicator in a sentinel population of young children and thus, may be valuable as tool for surveillance in the context of lymphatic filariasis elimination programs.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/sangue , Filariose Linfática/diagnóstico , Doenças Endêmicas , Parasitemia , Wuchereria bancrofti/imunologia , Animais , Criança , Pré-Escolar , Filariose Linfática/imunologia , Filariose Linfática/parasitologia , Ensaio de Imunoadsorção Enzimática , Métodos Epidemiológicos , Feminino , Haiti/epidemiologia , Humanos , Lactente , Estudos Longitudinais , Masculino , Microscopia , Fatores de Tempo , Wuchereria bancrofti/isolamento & purificaçãoRESUMO
The World Health Organization has called for an effort to eliminate Lymphatic Filariasis (LF) around the world. In regions where the disease is endemic, local production and distribution of medicated salt dosed with diethylcarbamazine (DEC) has been an effective method for eradicating LF. A partner of the Notre Dame Haiti program, Group SPES in Port-au-Prince, Haiti, produces a medicated salt called Bon Sel. Coarse salt is pre-washed and sprayed with a solution of DEC citrate and potassium iodate. Iodine levels are routinely monitored on site by a titrimetric method. However, the factory had no method for monitoring DEC. Critical analytical issues include 1) determining whether the amount of DEC in each lot of Bon Sel is within safe and therapeutically useful limits, 2) monitoring variability within and between production runs, and 3) determining the effect of a common local practice (washing salt before use) on the availability of DEC. This paper describes a novel titrimetric method for analysis of DEC citrate in medicated salt. The analysis needs no electrical power and requires only a balance, volumetric glassware, and burets that most salt production programs have on hand for monitoring iodine levels. The staff of the factory used this analysis method on site to detect underloading of DEC on the salt by their sprayer and to test a process change that fixed the problem.
Assuntos
Técnicas de Química Analítica , Dietilcarbamazina/análise , Filaricidas/análise , Iodo/química , Haiti , Humanos , Cloreto de Sódio na DietaRESUMO
Seven rounds of mass drug administration (MDA) have been administered in Leogane, Haiti, an area hyperendemic for lymphatic filariasis (LF). Sentinel site surveys showed that the prevalence of microfilaremia was reduced to <1% from levels as high as 15.5%, suggesting that transmission had been reduced. A separate 30-cluster survey of 2- to 4-year-old children was conducted to determine if MDA interrupted transmission. Antigen and antifilarial antibody prevalence were 14.3% and 19.7%, respectively. Follow-up surveys were done in 6 villages, including those selected for the cluster survey, to assess risk factors related to continued LF transmission and to pinpoint hotspots of transmission. One hundred houses were mapped in each village using GPS-enabled PDAs, and then 30 houses and 10 alternates were chosen for testing. All individuals in selected houses were asked to participate in a short survey about participation in MDA, history of residence in Leogane and general knowledge of LF. Survey teams returned to the houses at night to collect blood for antigen testing, microfilaremia and Bm14 antibody testing and collected mosquitoes from these communities in parallel. Antigen prevalence was highly variable among the 6 villages, with the highest being 38.2% (Dampus) and the lowest being 2.9% (Corail Lemaire); overall antigen prevalence was 18.5%. Initial cluster surveys of 2- to 4-year-old children were not related to community antigen prevalence. Nearest neighbor analysis found evidence of clustering of infection suggesting that LF infection was focal in distribution. Antigen prevalence among individuals who were systematically noncompliant with the MDAs, i.e. they had never participated, was significantly higher than among compliant individuals (p<0.05). A logistic regression model found that of the factors examined for association with infection, only noncompliance was significantly associated with infection. Thus, continuing transmission of LF seems to be linked to rates of systematic noncompliance.
Assuntos
Filariose Linfática/epidemiologia , Filariose Linfática/transmissão , Doenças Endêmicas , Filaricidas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/sangue , Criança , Pré-Escolar , Análise por Conglomerados , Filariose Linfática/tratamento farmacológico , Feminino , Haiti/epidemiologia , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Adulto JovemRESUMO
In 2000, annual mass administration of diethlycarbamazine and albendazole began in Leogane Commune, Haiti, to interrupt transmission of lymphatic filariasis (LF). After 5 years of treatment, microfilaremia, antigenemia, and mosquito infection rates were significantly reduced, but LF transmission was not interrupted. These finding have implications for other LF elimination programs.
Assuntos
Albendazol/administração & dosagem , Dietilcarbamazina/administração & dosagem , Filariose Linfática/epidemiologia , Filariose Linfática/prevenção & controle , Filaricidas/administração & dosagem , Programas Governamentais/normas , Albendazol/efeitos adversos , Albendazol/uso terapêutico , Animais , Dietilcarbamazina/efeitos adversos , Dietilcarbamazina/uso terapêutico , Quimioterapia Combinada , Filariose Linfática/tratamento farmacológico , Filariose Linfática/parasitologia , Filaricidas/efeitos adversos , Filaricidas/uso terapêutico , Haiti/epidemiologia , Humanos , Microfilárias/efeitos dos fármacos , Prevalência , Avaliação de Programas e Projetos de Saúde , Wuchereria bancrofti/efeitos dos fármacosRESUMO
BACKGROUND: Because lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk. METHODOLOGY/PRINCIPAL FINDINGS: To obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented - generally 60%-90% of program operation costs, excluding costs of donated medications. CONCLUSIONS/SIGNIFICANCE: MDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones.
Assuntos
Anti-Helmínticos/uso terapêutico , Filariose Linfática/tratamento farmacológico , Albendazol/economia , Albendazol/uso terapêutico , Anti-Helmínticos/economia , Burkina Faso/epidemiologia , Custos e Análise de Custo , Dietilcarbamazina/economia , Dietilcarbamazina/uso terapêutico , República Dominicana/epidemiologia , Tratamento Farmacológico/economia , Tratamento Farmacológico/métodos , Egito/epidemiologia , Elefantíase/tratamento farmacológico , Elefantíase/prevenção & controle , Filariose Linfática/prevenção & controle , Gana/epidemiologia , Haiti/epidemiologia , Humanos , Equipe de Assistência ao Paciente , Filipinas/epidemiologia , Tanzânia/epidemiologiaRESUMO
OBJECTIVES: In the global effort to eliminate lymphatic filariasis, mass drug administrations (MDAs) are organised annually. The success of this strategy depends on achieving high levels of drug coverage, which reduce the number of persons with circulating microfilariae and consequently transmission. Persons who consistently fail to participate in MDAs represent a potential threat to the goal of filariasis elimination. We wanted to know the drug coverage, the proportion of persons who were systematically non-compliant and factors associated with this behaviour. METHODS: We conducted three surveys following the third annual MDA of a filariasis elimination program in Leogane, Haiti: (1) a total population survey to determine coverage; (2) an adult survey to determine non-compliance and associated factors and (3) an urban survey to make a rural-urban comparison. RESULTS: During the third MDA, the overall surveyed coverage was 78.5% [95% confidence interval (CI) 74.4-82.6] A survey among adult population showed coverage estimates for persons >14 years old of 59.4% (95% CI 52.0-66.7), 61.0% (95% CI 55.0-67.4) and 67.3% (95% CI 60.5-74.0), for the first, second and third MDA respectively. The coverage in rural areas (78.3%) was significantly higher than in urban areas (68.3%, P < 0.05). Of the population > 14 years of age, 18% never took the drugs during any of three MDAs. These persons did not differ significantly from MDA participants by age, gender or other characteristics that we assessed. CONCLUSION: More research is needed to identify characteristics of systematically non-compliant persons in order to refine health education messages and improve distribution strategies to increase drug coverage.