RESUMO
The Global Program to Eliminate Lymphatic Filariasis has achieved extraordinary success in reducing transmission and preventing morbidity through mass drug administration (MDA) to the population at-risk. Brazil is the only currently using diethylcarbamazine citrate (DEC) alone for MDA, so an assessment of its effectiveness is needed. We report the trends of filarial markers in a cohort of 175 individuals infected with Wuchereria bancrofti in areas that underwent MDA in the city of Olinda, Northeastern Brazil. The prospective study was conducted between 2007 and 2012 (corresponding to five annual MDA rounds). The quantification of microfilaraemia (QMFF) was assessed by filtration. Circulating filarial antigen (CFA) was detected through immunochromatographic point-of-care test (POCT-ICT) and Og4C3-ELISA whereas antifilarial antibody titres (IgG4) were assessed through Bm14 assay. The CFA and IgG4 titres were measured by Optical Density (OD). The main characteristics at baseline, MDA coverage and the trend of filarial infection markers during follow up were described. The trend of filarial markers in relation to time (years of MDA), sex and age were analysed through Generalized Estimating Equations (GEE) models. The models demonstrated a significant decrease in all markers during MDA. The probability of remaining positive by QMFF and POCT-ICT diminished 70% and 46%, respectively, after each MDA round. There was a significant annual drop in CFA (-0.290 OD) and IgG4 antibodies titres (-0.303 OD). This study provides evidence that MDA with DEC alone can be effective in the elimination of LF in Brazil.
Assuntos
Dietilcarbamazina/administração & dosagem , Transmissão de Doença Infecciosa/prevenção & controle , Filariose Linfática/tratamento farmacológico , Filariose Linfática/epidemiologia , Doenças Endêmicas , Filaricidas/administração & dosagem , Administração Massiva de Medicamentos/métodos , Adolescente , Adulto , Idoso , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/sangue , Brasil/epidemiologia , Criança , Pré-Escolar , Testes Diagnósticos de Rotina , Filariose Linfática/prevenção & controle , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Carga Parasitária , Estudos Prospectivos , Resultado do Tratamento , Wuchereria bancrofti/efeitos dos fármacos , Adulto JovemRESUMO
The mutagenic effects of organophosphorate temephos on mice bone marrow cells was investigated through the micronucleus formation test. Doses of temephos (27.75; 55.5 e 111.0 mg/kg) were orally administered to males and females Swiss Webster mice. Cyclophosphamide (CPA, 25 mg/kg) per via i.p. and water (10 mL/kg) were administered in mice as positive and negative control groups, respectively. Mutagenic effects were evaluated from 24h to 72h after giving a single dose, and after nine doses of 111.0 mg/kg weekly administered. Ten thousand bone marrow cells per experimental group were analyzed. In the positive controls, the percentages of polychromatic erythrocytes micronucleus (PCEMN) at 24h after a single dose were 1.63% in male and 2.77% in female mice. No PCEMN was observed in the negative controls group. Gradually increasing temephos doses induced PCEMN in 2.61, 3.50, and 3.69% males and 1.02, 1.37, and 1.33% females, respectively. After 72h, CPA caused 0.05% of PCEMN in both males and females; and the temephos caused 0.92% in males and 0.18% in females. In mice administered with nine doses of CPA, PCEMN was detected in 0.15% males and 0.8% females, although PCEMN values were significantly higher in temephos receiving mice group. The mutagenic effects of temephos on both male and female mice were evidenced by chromosome alterations inducing micronucleus formation.
Foram investigados os efeitos mutagênicos do organofosforado temefós através da observação da formação de micronúcleos em eritrócitos policromáticos (PCEMN) da medula óssea de camundongos. Em camundongos Swiss Webster de ambos os sexos, foram administradas diferentes doses de temefós (27,75; 55,5 e 111,0 mg/kg) por via bucal-gástrica e água destilada (10 mL/kg) no grupo controle negativo; e ciclofosfamida (CPA) (25 mg/kg) foi administrada pela via i.p. no grupo controle positivo. Foram analisadas dez mil células da medula óssea por grupo experimental. Os efeitos mutagênicos foram avaliados nos períodos de 24, 48 e 72h após ministrar a dose única e após nove doses de 111,0 mg/kg (1/semana). Em 24h após a dose única de CPA, a formação de PCEMN foi observada em 1,63% dos camundongos machos e 2,77% em fêmeas. Não houve formação de PCEMN no grupo controle negativo. O temefós induziu PCEMN em 2,61%, 3,50% e 3,69% de animais machos e 1,02%, 1,37% e 1,33% em fêmeas. Após 72h, CPA induziu PCEMN em 0,05% de camundongos de ambos sexos e o temefós em 0,92% de machos e 0,18% em fêmeas. Após nove doses de CPA, houve a formação de PCEMN em 0,15% de machos e em 0,8% de fêmeas; para o temefós, os valores observados foram respectivamente de 0,53% e 0,11%. A ação mutagênica de temefós foi demonstrada pela indução de micronúcleos em camundongos de ambos sexos.