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M Albonico

Publications and source records attributed to M Albonico.

At least 19 recordsLinked to original sources
PubMed2004

Progress in the prevention and control of schistosomiasis and soil-transmitted helminthiasis.

In the last two decades important progress has been made in the understanding the epidemiology and the disease burden of schistosomiasis and soil-transmitted nematodes infection. In addition, practical tools for disease control have been developed and a strategy for the prevention and control of morbidy of schistosomaisis and soil-transmitted nematodes infection has been endorsed by the World Health Organization. This paper presents the recent progress in the prevention and control of these infections: the estimates of chronic and subtle morbidity in high risk groups and the evidence that these chronic and severe sequelae of infections can be reversed by appropriate treatment; the use of anthelminthic drugs during pregnancy and lactation; the relevance to control morbidity due to these infections also in pre-school children; the efficacy of anthelminthic drugs and the possible threat of drug resistance; price, quality and accessibility of treatment by delivering drugs through the school system and ways of reaching also non-enrolled school-age children. Finally, the strategy, targets and recommendations of the World Health Organization for the control of schistosomiasis and soil-transmitted nematodes infection are described.

Animals↗
PubMed2003

Efficacy of mebendazole and levamisole alone or in combination against intestinal nematode infections after repeated targeted mebendazole treatment in Zanzibar.

OBJECTIVE: To evaluate the efficacy of and resistance to mebendazole (500 mg) and levamisole (40 or 80 mg), alone or in combination, for the treatment of Ascaris lumbricoides, Trichuris trichiura and hookworm infections on Pemba Island - an area exposed to periodic school-based mebendazole treatment since 1994. METHODS: A randomized, placebo-controlled trial was carried out in 914 children enrolled from the first and fifth grades of primary schools. Stool samples collected at baseline and 21 days after treatment were examined by the Kato-Katz technique to assess the prevalence and intensity of helminth infection. FINDINGS: Efficacies of mebendazole and levamisole as single treatments against intestinal nematode infections were comparable with those in previous trials, but mebendazole treatment of hookworm infections gave significantly lower cure (7.6%) and egg reduction (52.1%) rates than reported in a study undertaken before the beginning of periodic chemotherapy (cure rate, 22.4%; egg reduction rate, 82.4%). Combined treatment with mebendazole and levamisole had a significantly higher efficacy against hookworm infections (cure rate, 26.1%; egg reduction rate, 88.7%) than either drug given alone. No difference in mebendazole efficacy was found in children who had been treated repeatedly compared with those who had not been treated previously. CONCLUSION: The overall efficacy of mebendazole against hookworm infections after periodic chemotherapy is reduced. The efficacy of benzimidazoles in chemotherapy-based control programmes should be monitored closely. Combined treatment with mebendazole and levamisole may be useful as a tool to delay the development of benzimidazole resistance.

Antinematodal Agents↗
PubMed2003

Methods to sustain drug efficacy in helminth control programmes.

Assessment of the efficacy of anthelminthic treatment in public health is a broad concept, which goes beyond parasitological methods and should be clearly defined according to several indicators of morbidity. Several factors may influence the efficacy of anthelminthic drugs. The quality of drug is an issue of great importance, especially when produced locally as a generic product and used in large-scale chemotherapy-based control programmes. Other factors include the drug-patient interaction, the host-parasite relationship, the diagnostic method used, genetic variations between parasite strains and induced drug resistance. Veterinary scientists have warned that drug resistance can be selected through frequent mass treatment of sheep and goats and have developed a body of knowledge on evaluation of efficacy and detection of resistance in nematodes of veterinary importance. In soil-transmitted nematodes infections of humans, the egg reduction rate (ERR), the egg hatch assay (EHA) and novel molecular biological techniques may be used to monitor drug efficacy in helminth control programmes and to detect early occurrence of resistance. Evidence of reduced drug efficacy of some anthelminthics has been suggested by recent studies and strategies to prevent or delay the emergence of drug resistance in human soil-transmitted nematodes.

Animals↗
PubMed2002

Soil-transmitted nematode infections and mebendazole treatment in Mafia Island schoolchildren.

In August 2000, a cross-sectional study was performed to assess the prevalence and intensity of soil-transmitted nematode infections in schoolchildren on Mafia Island. Hookworm infection was widespread (72.5% prevalence) whereas Trichuris trichiura was less prevalent (39.7%) and Ascaris lumbricoides was present at a low prevalence (4.2%), mainly in urban areas. In a subsample of the study population, both Necator americanus and Ancylostoma duodenale were found, although N. americanus was more prevalent. This survey was followed by a parasitological evaluation of mebendazole treatment using a single, 500-mg dose. The data on outcome were used for comparison with those from recent studies of similar treatment regimens in the neighbouring island of Pemba, Zanzibar, where periodic chemotherapy with mebendazole to schoolchildren has been implemented as part of a helminth-control programme since 1994. A higher efficacy of mebendazole against hookworm infection was found in Mafia Island (where a cure 'rate' of 31.3% and an egg-reduction 'rate' of 78.1% were recorded) when compared with that observed in Pemba Island, possibly indicating that hookworms may be developing mebendazole resistance on Pemba Island as a result of intense exposure to the drug there.

Adolescent↗
PubMed2001

Effects of iron supplementation and anthelmintic treatment on motor and language development of preschool children in Zanzibar: double blind, placebo controlled study.

OBJECTIVE: To measure the effects of iron supplementation and anthelmintic treatment on iron status, anaemia, growth, morbidity, and development of children aged 6-59 months. DESIGN: Double blind, placebo controlled randomised factorial trial of iron supplementation and anthelmintic treatment. SETTING: Community in Pemba Island, Zanzibar. PARTICIPANTS: 614 preschool children aged 6-59 months. MAIN OUTCOME MEASURES: Development of language and motor skills assessed by parental interview before and after treatment in age appropriate subgroups. RESULTS: Before intervention, anaemia was prevalent and severe, and geohelminth infections were prevalent and light-Plasmodium falciparum infection was nearly universal. Iron supplementation significantly improved iron status, but not haemoglobin status. Iron supplementation improved language development by 0.8 (95% confidence interval 0.2 to 1.4) points on the 20 point scale. Iron supplementation also improved motor development, but this effect was modified by baseline haemoglobin concentrations (P=0.015 for interaction term) and was apparent only in children with baseline haemoglobin concentrations <90 g/l. In children with a baseline haemoglobin concentration of 68 g/l (one standard deviation below the mean value), iron treatment increased scores by 1.1 (0.1 to 2.1) points on the 18 point motor scale. Mebendazole significantly reduced the number and severity of infections caused by Ascaris lumbricoides and Trichuris trichiura, but not by hookworms. Mebendazole increased development scores by 0.4 (-0.3 to 1.1) points on the motor scale and 0.3 (-0.3 to 0.9) points on the language scale. CONCLUSIONS: Iron supplementation improved motor and language development of preschool children in rural Africa. The effects of iron on motor development were limited to children with more severe anaemia (baseline haemoglobin concentration <90 g/l). Mebendazole had a positive effect on motor and language development, but this was not statistically significant.

Anemia, Iron-Deficiency↗
PubMed2001

School enrollment in Zanzibar linked to children's age and helminth infections.

UNLABELLED: School health programmes have been identified as a cost-effective strategy to reduce morbidity due to soil-transmitted helminths in the school-age population, but the low rate of school enrollment in developing countries is a major factor limiting their success. OBJECTIVE: The present study was conducted to identify reasons for non-enrollment and to evaluate differences in the occurrence of helminth infection between enrolled and non-enrolled children in Zanzibar, United Republic of Tanzania. METHOD: A questionnaire was submitted to 520 households to obtain information about enrollment and other socio-economic indicators. In addition, one school-age child was randomly selected in each household and investigated for soil-transmitted helminth infection. RESULTS: Overall, 71% of school-age children were enrolled. Enrollment increased with age. Only 41% of children under 9 years of age were enrolled compared to 91% in children older than 12 years. Enrollment is delayed because of an insufficient number of schools. Among non-enrolled school-age children, the proportion of heavy intensity infections was twice that of enrolled school-age children. CONCLUSIONS: Most of the non-enrolled school-age children live together with enrolled siblings in the same household, thereby representing an important opportunity for effective outreach activities. The effectiveness of the school-based helminth control programme in reducing the intensity of infection was confirmed. The significant gains achieved by enrolled school-age children in this study must be viewed as an attainable goal for the important numbers of non-enrolled school-age children in endemic areas. Decision-makers must ensure that outreach activities are included in helminth control programmes targeted to school-age children.

Adolescent↗
PubMed2001

Extending anthelminthic coverage to non-enrolled school-age children using a simple and low-cost method.

School health programmes are the basis of the strategy defined by WHO to reduce morbidity due to soil-transmitted nematodes and schistosomes in school age populations in developing countries. However, low rates of school enrollment can be a major factor limiting their success. In the present study enrolled children were informed by teachers on the date of the next deworming campaign and were invited to pass along this information to parents, siblings and friends of school-age. On the day of the deworming campaign, teachers were instructed to administer anthelminthics to enrolled and not enrolled school-age children present at school. In the month following the treatment day, information about coverage was collected by questionnaire in 257 households in two regions of Unguja Island, Zanzibar. Over 89% of school age children resulted treated (98.9% of those enrolled plus 60% of those not enrolled). The additional cost of treating non-enrolled is limited to the cost of providing additional doses of anthelminthic drug in each school. Non-enrolled school age children can easily, successfully and inexpensively included in school based deworming campaign. Managers of control programmes are invited to test this method adapting it in their particular and cultural environment.

Adolescent↗
PubMed2001

[Epidemiologic surveillance system and control of malaria in the central highlands of Madagascar: results 1999-2000].

The central highlands in Madagascar are characterized by an unstable occurrence of malaria with the risk of sporadic outbreaks. In major parts of the region DDT indoor spraying campaigns have been carried out from 1993 to 1998. This strategy was in 1999 replaced by another anti-vector intervention program targeting residual foci as detected by a surveillance and early warning system. This system is based on monitoring of presumptive malaria cases in the communities by which the number of presumptive cases exceeded a defined warning threshold value per month. The system was in the follow-up period shown to be very sensitive to variation of the coverage of anti-vector interventions: the number of presumptive cases decreased in the villages in which indoor spraying had been carried out and a minor increase was observed in those villages, where indoor spraying has been suspended. An increase of malaria cases was observed in 44 (20.8%) out of 212 study sites in the same period. The increase was in particular predominant in areas at lower attitude at the outer zones of the central highlands.

Altitude↗
PubMed2000

Field trial of a haemoglobin colour scale: an effective tool to detect anaemia in preschool children.

The objective of this study was to evaluate the performance of the Haemoglobin Colour Scale, developed by Stott and Lewis, to diagnose anaemia in a primary health care setting where anaemia was prevalent and severe. Three measures of anaemia were compared in 535 preschool children: haemoglobin based on the Haemoglobin Colour Scale, clinical assessment in three sites (conjunctiva, palm and nail bed) and haemoglobin based on a digital haemoglobinometer (HemoCue method) taken as gold standard. A statistically significant correlation (r = 0.80, coefficient = 0.77 and Y intercept = 2.33) was obtained between the results of the Haemoglobin Colour Scale and the HemoCue. In more than 80% of cases, the difference between the colour scale readings and the results of the HemoCue was within 1 g/dl. Of 415 anaemic children (Hb < 11 g/dl by HemoCue), 85.2% were so identified by the Haemoglobin Colour Scale and 19.7% were classified anaemic by clinical pallor. Of 19 severely anaemic children (Hb < 7 g/dl by HemoCue), 73.6% were identified as severely anaemic and 100% were classified as anaemic by the colour scale, 61.1% were classified as anaemic using clinical pallor. We found the Haemoglobin Colour Scale to be a useful tool in identifying anaemic and severely anaemic children. Efficiencies in term of cost, accuracy and time make it an important resource in primary health care settings in developing countries. Further testing with other staff in other settings is recommended to determine the usefulness of large-scale distribution.

Anemia↗
PubMed2000

Hookworms, malaria and vitamin A deficiency contribute to anemia and iron deficiency among pregnant women in the plains of Nepal.

Anemia and iron deficiency during pregnancy are prevalent in developing countries, but their causes are not always known. We assessed the prevalence and severity of anemia and iron deficiency and their association with helminths, malaria and vitamin A deficiency in a community-based sample of 336 pregnant women in the plains of Nepal. Hemoglobin, erythrocyte protoporphyrin (EP) and serum ferritin were assessed in venous blood samples. Overall, 72.6% of women were anemic (hemoglobin < 110 g/L), 19.9% had moderate to severe anemia (hemoglobin < 90 g/L) and 80.6% had iron deficiency (EP > 70 micromol/mol heme or serum ferritin < 10 microg/L). Eighty-eight percent of cases of anemia were associated with iron deficiency. More than half of the women (54.2%) had a low serum retinol concentration (<1.05 micromol/L), 74.2% were infected with hookworms and 19.8% had Plasmodium vivax malaria parasitemia. Hemoglobin, EP and serum ferritin concentrations were significantly worse and the prevalence of anemia, elevated EP and low serum ferritin was increased with increasing intensity of hookworm infection. Hookworm infection intensity was the strongest predictor of iron status, especially of depleted iron stores. Low serum retinol was most strongly associated with mild anemia, whereas P. vivax malaria and hookworm infection intensity were stronger predictors of moderate to severe anemia. These findings reinforce the need for programs to consider reducing the prevalence of hookworm, malaria infection and vitamin A deficiency where indicated, in addition to providing iron supplements to effectively control anemia.

Adolescent↗
PubMed2000

Malaria, hookworms and recent fever are related to anemia and iron status indicators in 0- to 5-y old Zanzibari children and these relationships change with age.

In Zanzibar and other tropical regions, iron deficiency, malaria and multiple helminth infections coexist. We addressed the following questions: 1) What are the predictors of low hemoglobin in Zanzibari preschool children? 2) Are indicators of iron status informative in this population? 3) Does malaria modify the relation of iron indicators to hemoglobin? We used multivariate regression to analyze cross-sectional data from a community-based sample of rural Zanzibari children who were not ill (n = 490; 4-71 mo of age) in whom we assessed hemoglobin, serum ferritin (SF), erythrocyte protoporphyrin (EP), serum transferrin receptor (TfR), recent fever, malaria parasitemia and helminth fecal egg counts. Of hemoglobin values, 80% were <100 g/L and 15.5% were <70 g/L. In children <18 mo of age, 40.2% of hemoglobin values were <70 g/L. Our primary findings were as follows: 1) In children <30 mo old, hemoglobin was associated with malaria but not hookworms, whereas in children >/=30 mo, hemoglobin was related to hookworms but not malaria. In the younger age group, male sex and recent fever also predicted lower hemoglobin. 2) The three iron indicators were informative in this population but did not reflect only iron status. Malaria elevated SF in younger children and TfR and EP in both age groups. Fever elevated SF in older children and EP in both age groups, but not TfR. 3) Malaria modified the relation of all three indicators to hemoglobin. The relation of SF to hemoglobin was weak overall, and absent in malaria-infected children. EP and TfR were strongly related to hemoglobin, but this relation was attenuated by malaria.

Age Factors↗
PubMed1999

Control strategies for human intestinal nematode infections.

In recent years significant progress has been made in understanding the ecology, epidemiology and related morbidity and development of new tools for the control of soil-transmitted helminths. Such knowledge has recognized the impact of helminth infections on the health of infected groups and has created a rational basis for their control. Schoolchildren harbour some of the most intense helminthic infections, which produce adverse effects on health, growth and scholastic performance. However, although great effort has been put into targeting school-age children, women of child-bearing age and pre-school children are two other groups at high risk of morbidity due to intestinal nematode infections. Highly effective and safety-tested, single-dose anthelminthic drugs are now available, permitting periodical deworming of schoolchildren and other high-risk groups at affordable prices. Four anthelminthics against all intestinal nematodes are included in the WHO Essential Drug List (albendazole, levamisole, mebendazole and pyrantel). Recently ivermectin has also been registered for use against Strongyloides stercoralis in humans. Several well-monitored country experiences have shown that chemotherapy-based control of morbidity due to soil-transmitted helminths is possible and highly cost-effective.

Africa↗
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

A controlled evaluation of two school-based anthelminthic chemotherapy regimens on intensity of intestinal helminth infections.

BACKGROUND: School-based deworming programmes have been promoted as a cost-effective strategy for control of nematode infection in developing countries. While numerous efficacy studies have been conducted, there is little information on actual programme effectiveness in areas of intense transmission. METHODS: A randomized trial of a school-based deworming programme was conducted in 12 primary schools on Pemba Island, Zanzibar. Four schools each were randomized to control, twice a year deworming with single dose mebendazole or three times a year deworming. Baseline and 12-month follow-up data on helminth infection using the Kato-Katz technique, demographic information and nutritional status were collected on 3028 children from March 1994 to May 1995. RESULTS: Intensity of infection measured as eggs per gram of faeces (epg) declined significantly for Ascaris lumbricoides, Trichuris trichiura and hookworm infections in both treatment groups. A. lumbricoides infection intensity declined 63.1% and 96.7% in the twice and three times per year treatment groups compared to the controls. T. trichiura infection intensity declined 40.4% and 75.9% respectively and hookworm intensity declined 35.3% and 57.2% respectively compared to control schools. CONCLUSIONS: These results suggest that school-based programmes can be a cost-effective approach for controlling the intensity of intestinal helminth infection even in environments where transmission is high.

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↗
PubMed1999

Control of epidemic malaria on the highlands of Madagascar.

The Malagashy national malaria control programme ('Programme National de Lutte contre le Paludisme', PNLP) has been developing, since 1996, an epidemiological early warning system for malaria epidemics in the Central Highlands with the support of the Italian Development Cooperation. The system is based on the monitoring of malaria morbidity (clinical diagnosis) in 536 peripheral health centres (CSB) of the Highlands. The intervention area corresponds to 27 districts of the Antananarivo and Fianarantsoa provinces (4.7 million inhabitants) and spans around 100,000 square km. For each CSB a monthly warning threshold, defined as the 1993-1996 monthly mean number of malaria cases plus two standard deviations, was established. Three levels of epidemic alert have been defined according to the number of times the cases of presumptive malaria surpassed the threshold and according to the reported presence of severe malaria cases. The surveillance system relies also on the monitoring, in district hospitals of the Highlands, of the Plasmodium falciparum infection rate among clinically diagnosed malaria cases. A total of 185,589 presumptive malaria cases, corresponding to a 42/1000 malaria incidence, were recorded in 1997 by the surveillance system. During the same year 184 alerts of 2nd degree were reported. During 1998 173,632 presumptive malaria cases corresponding to a 38/1000 incidence were reported and 207 alerts of 2nd degree were detected; 75 of these alerts were investigated with ad hoc surveys and 3 initial malaria epidemics identified and controlled. Out of 6884 presumptive malaria cases diagnosed in the district hospitals during 1997-1998, only 835 (12.1%) have been confirmed by microscopy (P. falciparum 81.7%, P. vivax 15.0%, P. malariae 2.5%, P. ovale 0.2%, mixed infections 0.6%); 22.4% of these infections were imported cases from coastal endemic areas. The efficiency of the system in monitoring the trend of malaria morbidity and in the rapid detection and response to malaria epidemics is still being evaluated.

Animals↗