RESUMO
Data have been collected for at least five years in areas where transmission of Schistosoma mansoni has been controlled in the West Indian island of St. Lucia. Faecal egg output, as determined by Bell's technique, was periodically determined in 625 people and the geometric mean egg loads by year and age-group (in 1970) are presented. Assuming that egg output is linearly related to worm load, that flukes exhibit exponential survival, and survival is independent of worm load, the mean life-span of flukes within each host is calculated. It is valid to pool results for hosts ten years of age and older and a mean life-span of 3.3 years (with approximate 95% limits of 2.7 to 4.5 years) for the flukes is obtained. Results for younger hosts were heterogeneous and no pooled estimate is determined but it is suspected that the mean life-spans are greater for these hosts. The validity of some of the assumptions is discussed.
Assuntos
Schistosoma mansoni/fisiologia , Esquistossomose/parasitologia , Adolescente , Adulto , Fatores Etários , Idoso , Animais , Criança , Pré-Escolar , Fezes/parasitologia , Humanos , Longevidade , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Índias OcidentaisRESUMO
Data have been collected for at least five years in areas where transmission of Schistosoma mansoni has been controlled in the West Indian island of St. Lucia. Faecal egg output, as determined by Bell's technique, was periodically determined in 625 people and the geometric mean egg loads by year and age-group (in 1970) are presented. Assuming that egg output is linearly related to worm load, that flukes exhibit exponential survival, and survival is independent of worm load, the mean life-span of flukes within each host is calculated. It is valid to a mean life-span of 3.3 years (with approximate 95 percent limits of 2.7 to 4.5 years) for the flukes is obtained. Results for younger hosts were heterogeneous and no pooled estimate is determined but it is suspected that the mean life-spans are greater for these hosts. The validity of some of the assumptions is discussed (AU)
Assuntos
Humanos , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , 21003 , Schistosoma mansoni/fisiologia , Esquistossomose/parasitologia , Fatores Etários , Fezes/parasitologia , Longevidade , Contagem de Ovos de ParasitasRESUMO
A method is described for the supervision of technicians engaged in microscopical screening of large numbers of stools for Schistosoma mansoni ova. The scheme presents graphically a regularly updated longitudinal evaluation of both individual and group standards of technical competence.
Assuntos
Fezes/parasitologia , Ciência de Laboratório Médico/normas , Contagem de Ovos de Parasitas/métodos , Schistosoma mansoni , Animais , Humanos , Métodos , Controle de Qualidade , Índias OcidentaisRESUMO
A method is described for the supervision of technicians engaged in microscopical screening of large numbers of stools for Schistosoma mansoni ova. The scheme presents graphically a regular updated longitudinal evaluation of both individual and group standards of technical competence (AU)