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A Montresor

Publications and source records attributed to A Montresor.

29 records · Page 2Linked to original sources
PubMed1999

Planning chemotherapy based schistosomiasis control: validation of a mathematical model using data on Schistosoma haematobium from Pemba, Tanzania.

A mathematical model, based on a deterministic differential equation framework, has been developed to predict the impact of community chemotherapy programmes for human schistosomiasis. Here, this model is validated using data collected from a long-term control programme for urinary schistosomiasis on the island of Pemba, Zanzibar, United Republic of Tanzania, initiated in 1986 and still ongoing, in which schoolchildren were offered praziquantel chemotherapy every 6 months. Prevalence of infection and blood in urine were monitored in all the schools (total 26000 children from 60 schools) and more detailed data were collected in selected evaluation schools. Model predictions were run by using the initial prevalence as input. The predictions were very close to the observed decreases in prevalence and in prevalence of blood in urine. The correspondence improved further when the data were combined, going from single school level to district, and when the entire data set was combined. The accuracy of the predictions suggests that this model could be used as a tool to predict the consequences of chemotherapy control programmes. It is currently in press as a Windows software package under the name of 'EpiSchisto'.

Adolescent↗
PubMed1999

Independent evaluation of the Nigrosin-Eosin modification of the Kato-Katz technique.

A new modified quantitative Kato-Katz thick-smear technique for the detection of helminth eggs in faeces preserves hookworm eggs unaltered for a long time, while with the classic Kato-Katz technique, they disappear after approximately 2 h in tropical climates and thus slides must be read within hours after sample collection. For an independent comparison of these two laboratory techniques, faecal smears from 263 school children were examined in two surveys and prevalence, intensity of infection and costs of surveys calculated. There was no statistical difference between the methods in detecting prevalence and stratification of the sample in different classes of intensity. While there was no statistical difference for the arithmetic mean of the epg for T. trichiura and only a small difference for A. lumbricoides (P=0.04), we observed a highly significant difference for hookworm mean intensities of infections (P<0.001). From the public health viewpoint both methods provided similar results, but due to its simplicity and widespread use the classical Kato-Katz technique remains first choice for community investigation of soil-transmitted nematodes. However, the Nigrosin-Eosin approach has several advantages and can be a valuable alternative in certain circumstances.

Animals↗
PubMed1999

Clinical pallor is useful to detect severe anemia in populations where anemia is prevalent and severe.

Clinical pallor is recommended as a simple way to detect severe anemia, but more data are needed on its accuracy and usefulness when assessed by nonphysicians in diverse settings. We measured hemoglobin and trained non-physician health workers to assess clinical pallor of the conjunctiva, palm and nail beds in five population samples in Nepal and Zanzibar, where severe anemia is common. In total, 5,760 individuals were examined, 3,072 of whom were anemic and 192 of whom had severe anemia (hemoglobin <70 g/L). The prevalence of pallor did not correspond to the prevalence of anemia or severe anemia in the groups studied. However, in all studies, pallor at each anatomical site was associated with a significantly lower hemoglobin concentration. The relative performance of different anatomical sites was not consistent among studies, and we recommend that multiple sites be assessed. Pallor at any of the three sites detected severe anemia with >84% specificity. However, the sensitivity varied from 81% in Nepalese postpartum women to 29% in Zanzibari preschoolers in 1996. Overall estimates for sensitivity and specificity were 50 and 92%, respectively. Although imperfect, use of pallor to screen and treat severe anemia by primary care providers is feasible and worthwhile where severe anemia is common. Usually, the majority of persons with severe anemia will be detected at practically no cost. Many people who are not severely anemic will also receive treatment, but the costs of this error are low compared to the benefits.

Adolescent↗
PubMed1997

Control of schistosomiasis--a global picture.

The control of schistosomiasis has been a challenging task for most endemic countries. Thus, despite the concerted efforts to date, schistosomiasis remains a major public health concern, second only to malaria in the tropics and subtropics. In this review, Lorenzo Savioli and colleagues highlight changes in schistosomiasis prevalence and distribution over the past decades, discuss the success and limitations of the various control strategies, and present possible control initiatives for the future.

Journal Article↗
PubMed1997

[Intestinal parasitic infections and schistosomiasis in the valley of the Senegal river in the Islamic Republic of Mauritania].

An epidemiological survey was carried out in the Trarza and Brakna regions of the Senegal River valley in Mauritania prior to implementation of a program to control intestinal parasitic infection and schistosomiasis. A total of 1297 school children between the ages of 5 and 12 years from a randomized selection of villages in the region were examined to determine the prevalence and intensity of intestinal parasitic infections and schistosomiasis. Overall prevalence was 38.1% for intestinal parasitic infection, 7.1% for intestinal schistosomiasis, and 17.1% for urinary schistosomiasis. Analysis of weight and height as indicators of nutritional status indicated that 40.9% of the children examined were under the 10th percentile of the weight-for-height indicator and that there was a statistically significant correlation between malnutrition, diarrhea, and intestinal parasitic infection (p < 0.0001). Measurement of hemoglobin levels showed that 50.4% of children were anemic (hemoglobin level < 11 g/dl) and that there was a correlation between anemia and infection by Schistosoma haematobium. This is the first epidemiological survey on intestinal parasitic infections in Mauritania and the first study on Schistosoma mansoni on the Mauritanian side of the Senegal River. Findings suggest not only that implementation of a program to control intestinal parasitic infection and schistosomiasis is needed in the region but also that it should be associated with a food/iron supplementation program and growth monitoring.

Anemia↗
PubMed1997

Parasitic infections in Pemba Island school children.

Intestinal helminths, schistosomiasis and malaria have been recognised for decades to be major public health problems in Zanzibar, Tanzania. During the evaluation of the impact of the Zanzibar Helminth Control Programme, baseline parasitological data on 3,605 school children were collected in Pemba Island. Prevalence of intestinal helminth infections was 72%, 94% and 96% for Ascaris lumbricoides, Trichuris trichiura and hookworm, respectively. Thirty one percent of children tested positive for haematuria, a reliable indicator of urinary schistosomiasis in the study area. Malaria parasites were found in 61% of children. Hookworm infections and haematuria were more prevalent in boys. Sixty seven percent of the children were infected with all the three helminths, and 28% harboured double infection. No association was found between intestinal helminths and schistosomiasis or malaria. Children living in rural areas were more heavily infected with hookworms, schistosomiasis and malaria compared to children in towns. Results from this study provided relevant information for designing a "plan of action" for the integrated control of filariasis, intestinal helminths, malaria and schistosomiasis in Zanzibar.

Adolescent↗
PubMed1997

[Preliminary survey of a school health program implementation in Guinea].

The Sectorial Adjustment Education Program implemented in Guinea by the Ministry of Pre-University Education in 1995 includes health-related measures. An important part is the fight against parasitosis and in particular against intestinal helminth infection which has been shown to impair cognitive function in school children. In order to obtain data for this purpose, a survey was carried out in 7 subprefectures across the country. A total of 1,649 children were examined to determine the prevalence in each school of macroscopic hematuria-related schistosomiasis and of various intestinal helminthiasis in stools. In 1468 of these children blood tests were also made to measure hemoglobin levels and detect malarial hematozoons. Overall prevalence rates were 60.0% for soil-transmitted nematodes, 9.1% for urinary schistosomiasis, 57.6% for blood plasmodium, and 57.0% for anemia. Hemoglobin levels were lower in children presenting plasmodium, multiple parasitic infection, and high ankylostoma burdens. Prevalence rates varied widely between regions indicating differences in therapeutic measures. In two villages more than 200 children not attending school who had been informed by school children were treated. This word-of-mouth effect shows that school health programs are also useful to reach children outside the school health system.

Child↗
PubMedDate not supplied

Field test of the 'dose pole' for praziquantel in Zanzibar.

A graduated pole for height measurement, estimating the number of praziquantel tablets needed for treatment, was field-tested on 1289 children in Zanzibar. A bathroom-type scale performed better than the dose pole in delivering the optimal dose (40-60 mg/kg) and the 2 methods performed similarly in delivering a dose considered appropriate (30-60 mg/kg).

Anthelmintics↗