NICU medication errors: identifying a risk profile for medication errors in the neonatal intensive care unit.

OBJECTIVE: To identify a risk profile for harmful medication errors in the neonatal intensive care unit (NICU). STUDY DESIGN: A retrospective cross-sectional study on NICU medication error reports submitted to MEDMARX between 1 January 1999, and 31 December 2005. The Rao-Scott modified chi(2) test was used for analysis. RESULT: 6749 NICU medication error reports were submitted by 163 health-care facilities. Administering errors accounted for approximately one half of errors, and human factors were the most frequently cited cause of error. Patient age was not associated with an increased likelihood of an error being harmful (P=0.11). Error reports involving Institute for Safe Medication Practices (ISMP) High-Alert Medications, occurring in the prescribing phase of medication processing, or involving equipment/delivery device failures were more likely to be harmful (P< or =0.05). CONCLUSION: Risk factors for harmful medication error reports include use of ISMP High-Alert Medications, the prescribing phase of the medication use process, and failure of equipment/delivery devices.

Global epidemiology, ecology and control of soil-transmitted helminth infections.

Soil-transmitted helminth (STH) infections are among the most prevalent of chronic human infections worldwide. Based on the demonstrable impact on child development, there is a global commitment to finance and implement control strategies with a focus on school-based chemotherapy programmes. The major obstacle to the implementation of cost-effective control is the lack of accurate descriptions of the geographical distribution of infection. In recent years, considerable progress has been made in the use of geographical information systems (GIS) and remote sensing (RS) to better understand helminth ecology and epidemiology, and to develop low-cost ways to identify target populations for treatment. This review explores how this information has been used practically to guide large-scale control programmes. The use of satellite-derived environmental data has yielded new insights into the ecology of infection at a geographical scale that has proven impossible to address using more traditional approaches, and has in turn allowed spatial distributions of infection prevalence to be predicted robustly by statistical approaches. GIS/RS have increasingly been used in the context of large-scale helminth control programmes, including not only STH infections but also those focusing on schistosomiasis, filariasis and onchocerciasis. The experience indicates that GIS/RS provides a cost-effective approach to designing and monitoring programmes at realistic scales. Importantly, the use of this approach has begun to transition from being a specialist approach of international vertical programmes to becoming a routine tool in developing public sector control programmes. GIS/RS is used here to describe the global distribution of STH infections and to estimate the number of infections in school-age children in sub-Saharan Africa (89.9 million) and the annual cost of providing a single anthelmintic treatment using a school-based approach (US$5.0-7.6 million). These are the first estimates at a continental scale to explicitly include the fine spatial distribution of infection prevalence and population, and suggest that traditional methods have overestimated the situation. The results suggest that continent-wide control of parasites is, from a financial perspective, an attainable goal.

Immuno-epidemiology of Ascaris lumbricoides infection in a high transmission community: antibody responses and their impact on current and future infection intensity.

The role of the humoral immune system in human infection with Ascaris lumbricoides remains unclear. This study documents an epidemiological investigation in a highly endemic community in Vietnam, whereby serum antibody levels were assessed before treatment and after a 6-month reinfection period. These data were examined by correlation with infection status using an age-structured approach in an attempt to help shed light on the role of the humoral immune response. The first part of this study characterized levels of all serum antibody isotypes from the community in response to antigens of both adult and larval A. lumbricoides. Data were assessed in terms of their relation to host age and infection intensity with the aim to provide a broadly detailed account of immune responses to the parasite. In the second part, antibody responses to both life-stages of A. lumbricoides in serum samples collected before anthelmintic chemotherapy were analysed in relation to intensity of re-infection with the parasite 6 months following treatment. The results suggest that antibody responses may not confer protection from current infection or re-infection with A. lumbricoides and may not serve as reliable indicators of future infection intensity. Our results thereby lend support to the theory that immunity to A. lumbricoides may not be based on the humoral immune system.

Sequence variation in the Trichuris trichiura beta-tubulin locus: implications for the development of benzimidazole resistance.

Benzimidazole resistance has evolved in a variety of organisms and typically results from mutations in the beta-tubulin locus at specific amino acid sites. Despite widespread treatment of human intestinal nematodes with benzimidazole drugs, there have been no unambiguous reports of resistance. However, since beta-tubulin mutations conferring resistance are generally recessive, frequencies of resistance alleles less than 30% would be difficult to detect on the basis of drug treatment failures. Here we investigate sequence variation in a 1079 bp segment of the beta-tubulin locus in the human whipworm Trichuris trichiura from 72 individual nematodes from seven countries. We did not observe any alleles with amino acid mutations indicative of resistance, and of 40 point mutations there were only four non-synonymous mutations all of which were singletons. Estimated effective population sizes are an order of magnitude lower than those from another nematode species in which benzimidazole resistance has developed (Haemonchus contortus). Both the lower diversity and reduced population sizes suggest that benzimidazole resistance is likely to evolve less rapidly in Trichuris than in trichostrongyle parasites of livestock. We observed moderate levels of population subdivision (Phi(ST)=0.26) comparable with that previously observed in Ascaris lumbricoides, and identical alleles were frequently found in parasites from different continents, suggestive of recent admixture. A particularly interesting feature of the data is the high nucleotide diversities observed in nematodes from the Caribbean. This genetic complexity may be a direct result of extensive admixture and complex history of human populations in this region of the world. These data should encourage (but not make complacent) those involved in large-scale benzimidazole treatment of human intestinal nematodes.

Schistosomiasis, helminth infection and health education in Tanzania: achieving behaviour change in primary schools.

Over a period of one school year a study was carried out into the feasibility and effectiveness of introducing active teaching methods into primary schools in Tanzania with a view to enhancing health education. The Lushoto Enhanced Health Education Project had as a focus personal hygiene with reference to the control of schistosomiasis and helminth infections. When a randomly selected group of children were compared with a comparison group there was evidence of changes in both knowledge and health-seeking behaviour. The passing of messages from children to the community met with mixed results. The observed changes were still evident over 1 year after the project had ended.

Effects of dietary ingredients on manure characteristics and odorous emissions from swine.

Two feeding studies were conducted to examine the impact of dietary inclusion of specific feed ingredients on manure characteristics and manure odor. In one study, 72 finishing pigs were used to evaluate the effects of distillers dried grains with solubles (DDGS) on pig performance, manure characteristics, and odorous emissions. Three diets containing 0, 5, and 10% DDGS were fed during six 4-wk feeding periods. Week 1 served as a dietary adjustment period. Animals were housed in two feeding rooms (six pigs/room) with one treatment/room. A new group of animals (average initial BW = 85.8 kg) was used for each feeding period. Diets were replicated four times. Rooms were equipped with individual shallow manure storage pits that were cleaned once weekly (d 7). On d 4 and 7 of each week, manure pit samples, for chemical analyses, and air samples, for olfactometry analysis, were collected from each room. Odor dilution threshold was greater on d 7 than on d 4 of manure storage across all treatments (P < 0.01). No treatment differences in manure composition were noted. In the second study, weaned pigs (approximately 5 wk old) were fed isonitrogenous diets containing 0, 1.5, or 3% bloodmeal. Pigs were housed by diet (three pigs/diet) in one of four individual feeding rooms. A new group of pigs was used for each of the two, 4-wk feeding periods. During period 1, the 3% bloodmeal diet was fed in two of the four rooms; the 0% bloodmeal diet was fed in two rooms during period 2. Manure samples, for chemical analyses, and air samples, for olfactometry analysis, were collected 2 d per week (d 4 and d 6) from each room during wk 2 through 4. No significant treatment differences were observed for odor dilution threshold (P = 0.30). Longer manure storage time, 6 d vs 4 d, resulted in a larger odor dilution ratio (P < 0.01). Manure composition was unaltered by storage time. Results suggest that odor intensifies during storage.

Heavy schistosomiasis associated with poor short-term memory and slower reaction times in Tanzanian schoolchildren.

Cross-sectional studies of the relationship between helminth infection and cognitive function can be informative in ways that treatment studies cannot. However, interpretation of results of many previous studies has been complicated by the failure to control for many potentially confounding variables. We gave Tanzanian schoolchildren aged 9-14 a battery of 11 cognitive and three educational tests and assessed their level of helminth infection. We also took measurements of an extensive range of potentially confounding or mediating factors such as socioeconomic and educational factors, anthropometric and other biomedical measures. A total of 272 children were moderately or heavily infected with Schistosoma haematobium, hookworm or both helminth species and 117 were uninfected with either species. Multiple regression analyses, controlling for all confounding and mediating variables, revealed that children with a heavy S. haematobium infection had significantly lower scores than uninfected children on two tests of verbal short-term memory and two reaction time tasks. In one of these tests the effect was greatest for children with poor nutritional status. There was no association between infection and educational achievement, nor between moderate infection with either species of helminth and performance on the cognitive tests. We conclude that children with heavy worm burdens and poor nutritional status are most likely to suffer cognitive impairment, and the domains of verbal short-term memory and speed of information processing are those most likely to be affected.

Predicting the distribution of urinary schistosomiasis in Tanzania using satellite sensor data.

In this paper, remotely sensed (RS) satellite sensor environmental data, using logistic regression, are used to develop prediction maps of the probability of having infection prevalence exceeding 50%, and warranting mass treatment according to World Health Organization (WHO) guidelines. The model was developed using data from one area of coastal Tanzania and validated with independent data from different areas of the country. Receiver operating characteristic (ROC) analysis was used to evaluate the model's predictive performance. The model allows reasonable discrimination between high and low prevalence schools, at least within those geographical areas in which they were originally developed, and performs reasonably well in other coastal areas, but performs poorly by comparison in the Great Lakes area of Tanzania. These results may be explained by reference to an ecological zone map based on RS-derived environmental data. This map suggests that areas where the model reliably predicts a high prevalence of schistosomiasis fall within the same ecological zone, which has common intermediate-host snail species responsible for transmission. By contrast, the model's performance is poor near Lake Victoria, which is in a different ecological zone with different snail species. The ecological map can potentially define a template for those areas where existing models can be applied, and highlight areas where further data and models are required. The developed model was then used to provide estimates of the number of schoolchildren at risk of high prevalence and associated programme costs.

Community perception of school-based delivery of anthelmintics in Ghana and Tanzania.

This paper presents the results of an evaluation of community perception of two large-scale, government-run, school-based health programmes delivering anthelmintic drugs to primary school children, in Ghana (80 442 children in 577 schools) and Tanzania (110 000 children in 352 schools). Most teachers (96% in Ghana and 98% in Tanzania) were positive about their role in the programme, including administration of anthelmintic drugs, and parents and children fully accepted their taking on this role. The benefits of the programme were apparent to teachers, parents and children in terms of improved health and well-being of the children. Over 90% of parents in both Ghana and Tanzania indicated a willingness to pay for the continuation of drug treatment. The evaluation also highlighted areas that are critical to programme effectiveness, such as communication between schools and parents, the issue of collaboration between the health and education sectors, parents' perception of the importance of helminth infection as a serious and chronic health problem (compared with more acute and life threatening illnesses such as malaria), and who should pay for treatment of side-effects.

Development and validation of a 'tablet pole' for the administration of praziquantel in sub-Saharan Africa.

A pole estimating, for each individual, the number of praziquantel tablets needed for treatment according to height was tested in 20 data sets (n = 25,688). In more than 98% of the cases the indicated dose was within the range that has proven efficacious and safe (30 and 60 mg/kg).

Evaluation of efficacy of school-based anthelmintic treatments against anaemia in children in the United Republic of Tanzania.

OBJECTIVE: To determine the impact of deworming on anaemia as part of a large-scale school-based anthelmintic treatment programme in the Tanga Region of the United Republic of Tanzania. METHODS: Both the reduction in the prevalence of anaemia and the cost per case prevented were taken into consideration. Cross-sectional studies involved parasitological examination and anaemia evaluation before and at 10 months and 15 months after schoolchildren were dewormed. FINDINGS: Baseline studies indicated that the prevalence of anaemia (haemoglobin < 110 g/l) was high (54%) among schoolchildren, particularly those with high intensities of hookworm and schistosomiasis. Attributable fraction analysis suggested that hookworm and schistosomiasis were responsible for 6% and 15% of anaemia cases, respectively. Fifteen months after deworming with albendazole and praziquantel the prevalence of anaemia was reduced by a quarter and that of moderate-to-severe anaemia (haemoglobin <90 g/l) was reduced by nearly a half. The delivery of these anthelmintics through the school system was achieved at the relatively low cost of US$ 1 per treated child. The cost per anaemia case prevented by deworming schoolchildren was in the range US$ 6-8, depending on the haemoglobin threshold used. CONCLUSIONS: The results suggested that deworming programmes should be included in public health strategies for the control of anaemia in schoolchildren where there are high prevalences of hookworm and schistosomiasis.

An association between chronic undernutrition and educational test scores in Vietnamese children.

OBJECTIVE: To examine the association between results of educational tests and the anthropometric status of schoolchildren. DESIGN: Cross-sectional data collected during the baseline survey of a randomised trial. SETTING: Eighty-one primary schools in three districts of northern Vietnam. SUBJECTS: A total of 3055 schoolchildren enrolled in class 3 and born in 1990. MAIN OUTCOME MEASURES: Tests of mathematics and Vietnamese language developed not to show floor or ceiling effects, and Z-scores of height-for-age, weight-for-age and weight-for-height. RESULTS: After controlling for age, sex, district and school the results of test scores in both mathematics and Vietnamese were significantly negatively correlated with Z-scores of height-for-age (P<0.001) and weight-for-age (P<0.001), but not with weight-for-height (P=0.75). CONCLUSIONS: A cross-sectional negative association was observed in Vietnamese primary school children between indicators of chronic undernutrition and tests of educational achievement. SPONSORSHIP: The study was funded by donors to the Partnership for Child Development including the Rockefeller Foundation and the World Bank.

Placebo-controlled community trial of four cycles of single-dose diethylcarbamazine or ivermectin against Wuchereria bancrofti infection and transmission in India.

A double-blind placebo-controlled trial was carried out in 1994-98 to compare the effects of 4 cycles of single-dose diethylcarbamazine (DEC) or ivermectin on prevalence and geometric mean intensity (GMI) of microfilaraemia in the human population, infection rates in the vector population, and transmission intensity of Culex-transmitted Wuchereria bancrofti in rural areas in Tamil Nadu state, south India. Fifteen villages (population approximately 26,800) were included in the study: 5 villages each were randomly assigned to community-wide treatment with DEC or ivermectin or placebo. People over 14 kg bodyweight received DEC 6 mg/kg, ivermectin 400 micrograms/kg or a placebo, all identically packaged. After 2 cycles of treatment at a 6-month interval, the code was broken and the study continued as an open trial, with third and fourth cycles of treatment at a 12-month interval; 54-77% of eligible people (20,872) received treatment during the 4 cycles. Microfilaraemia prevalence and GMI fell by 48% and 65% with DEC and 60% and 80% with ivermectin respectively after 4 cycles of treatment. There was no change in the incidence of acute adenolymphangitis. Infection in resting mosquitoes fell significantly in all arms: 82%, 78% and 42% in the ivermectin, DEC and placebo arm, respectively. Landing mosquitoes also showed the same trend. The decline in infectivity was significant for resting (P < 0.05) and landing mosquitoes (P < 0.05) with ivermectin and DEC (P < 0.05), and for neither in the placebo group (P > 0.05). Transmission intensity was reduced by 68% with ivermectin and 63% with DEC. Transmission was apparently interrupted in 1 village with ivermectin, but infected resting mosquitoes were consistently found in this village. Single-dose community-level treatment with DEC or ivermectin is effective in reducing W. bancrofti infection in humans and mosquitoes, and may result in total interruption of transmission after several years of control. There is an immediate need to define the role of vector, parasite and community factors that influence the elimination of lymphatic filariasis, particularly the duration of treatment vis-à-vis efficacy of drugs, treatment compliance and efficiency of vectors.

The effects of sex and age of responders on the reliability of self-diagnosed infection: a study of self-reported urinary schistosomiasis in Tanzanian school children.

Self-reported schistosomiasis has been proven to be a reliable estimation of the prevalence of infection in school children. For the first time, this paper presents an investigation into the use of self-reported schistosomiasis to estimate the prevalence of urinary schistosomiasis, due to Schistosoma haematobium, in school children with particular emphasis on whether the age and sex of respondents influences the reliability of diagnosis. It is shown first, that the prevalence and intensity of infection vary with sex; infection in boys is always more prevalent and more intense than in girls of the same age and second, that age and sex influence the reliability of self-reported schistosomiasis as a diagnostic method. Age and sex are factors that should be considered when implementing control measures in endemic areas.

Multiple helminth infections in children: impact and control.

Parasitic worm infections are amongst the most widespread of all chronic human infections. It is estimated that there are more than 3 billion infections in the world today. In many low income countries it is often more common to be infected than not to be. Indeed, a child growing up in an endemic community can expect be infected soon after weaning, and to be infected and constantly reinfected for the rest of her or his life. Infection is most common amongst the poorest and most disadvantaged communities, and is typically most intense in children of school going age. As the risk of morbidity is directly related to intensity of infection, it follows that children are the most at risk from the morbid effects of disease. Multiparasite infections are also common in such communities and there is evidence that individuals harbouring such infections may suffer exacerbated morbidity, making children even more vulnerable. Thus, these infections pose a serious threat to the health and development of children in low income countries. For many years, the need to control these infections has lain uncontested, and with the advent of broad-spectrum anthelminthic drugs that are cheap, safe and simple to deliver, control has at last become a viable option for many communities. Furthermore, there is now increased emphasis being placed on a multispecies approach as a cost-effective mechanism to control the morbidity of virtually all the major helminthic infections of humans.

The potential of rapid screening methods for Schistosoma mansoni in western Kenya.

Data from 46 schools in western Kenya were used to investigate the performance of school-based questionnaires, on reported blood in stool and water-contact patterns, as indicators of the prevalence of human infection with Schistosoma mansoni. Prevalence of infection was associated with the prevalence of self-reported blood in stool, recent history of swimming and recent history of fishing. It was shown that use of a threshold of 30% of subjects reporting blood in stool would identify 42.9% of the 'high-prevalence' schools (i.e. prevalence > or = 50%) and 87.5% of the 'low-prevalence' schools (i.e. prevalence < 50%). A threshold of 25% reporting swimming would identify 57.1% and 93.7% of the high- and low-prevalence schools, respectively. Blood in stool appears to be too coarse an indicator to identify schools for mass treatment correctly. Although the use of multiple questions improved the diagnostic performance of the questionnaire in identifying the high-prevalence schools, it was unclear how questions can best be combined in other settings. However, there is a direct relationship between prevalence of S. mansoni infection and distance of the school from the lakeshore; analysis indicated that use of a threshold of 5 km from the lakeshore would correctly identify most (90%) of both the low- and high-prevalence schools. Distance to the lakeshore may therefore be used to screen schools in much of East Africa (i.e. those areas close to the Great Lakes where the infection is known to be prevalent and where much of the region's population is concentrated). In other areas of transmission, such as irrigation areas, further studies are still required.

Anaemia in schoolchildren in eight countries in Africa and Asia.

OBJECTIVE: To report on the haemoglobin concentrations and prevalence of anaemia in schoolchildren in eight countries in Africa and Asia. DESIGN: Blood samples were collected during surveys of the health of schoolchildren as a part of programmes to develop school-based health services. SETTING: Rural schools in Ghana, Indonesia, Kenya, Malawi, Mali, Mozambique, Tanzania and Vietnam. SUBJECTS: Nearly 14 000 children enrolled in basic education in three age ranges (7-11 years, 12-14 years and > or =15 years) which reflect the new UNICEF/WHO thresholds to define anaemia. RESULTS: Anaemia was found to be a severe public health problem (defined as >40% anaemic) in five African countries for children aged 7-11 years and in four of the same countries for children aged 12-14 years. Anaemia was not a public health problem in the children studied in the two Asian countries. More boys than girls were anaemic, and children who enrolled late in school were more likely to be anaemic than children who enrolled closer to the correct age. The implications of the four new thresholds defining anaemia for school-age children are examined. CONCLUSIONS: Anaemia is a significant problem in schoolchildren in sub-Saharan Africa. School-based health services which provide treatments for simple conditions that cause blood loss, such as worms, followed by multiple micronutrient supplements including iron, have the potential to provide relief from a large burden of anaemia.

Health and cultural factors associated with enrolment in basic education: a study in rural Ghana.

This inter-disciplinary study compares the health status of school-age children in Ghana, both enrolled and non-enrolled, and examines these results within a wider socio-economic and socio-cultural context including kinship and livelihood. Children matched for age and sex who were not enrolled in Primary School were significantly shorter and more stunted than enrolled children were, and 70% of all Primary school-age children were anaemic. Young children from farming communities were significantly more undernourished than children from fishing communities. Adolescent non-enrolled boys were more heavily infected with Schistosoma haematobium, and were more likely to be anaemic than enrolled adolescent boys. The data indicate how health and health related factors may influence and affect enrolment and how socio-economic indicators, livelihood, and kinship may also constrain enrolment and, in turn, affect child health. This study sheds light on the complex factors that may influence enrolment in education and provides novel data on the similarities and differences between the health of enrolled and non-enrolled children in rural Ghana.

Autoradiography.

This overview provides a thorough discussion of the theory and application of autoradiography for determining the spatial distribution of radioisotope-labeled substances within a membrane or specimen material. The various types of film are discussed along with instructions on their correct handling. Quantitative autoradiography is described as a means of calibrating experimental results. Importantly, specific guidelines are given for pre-flashing film, along with exposure and processing procedures.