Search PubMed⌕ Search

Biomedical subjects

T W Gyorkos

Publications and source records attributed to T W Gyorkos.

At least 19 recordsLinked to original sources
PubMed1999

Effect of consumption of food cooked in iron pots on iron status and growth of young children: a randomised trial.

BACKGROUND: In less-developed countries, novel strategies are needed to control iron-deficiency anaemia, the most common form of malnutrition. METHODS: We undertook a community-based randomised controlled trial to assess the effects of iron or aluminium cooking pots in young Ethiopian children. Analysis was by intention-to-treat. The primary outcomes were change in children's haemoglobin concentration, weight, or length over the study period. We also did a laboratory study of total and available iron in traditional Ethiopian foods cooked in iron, aluminium, and clay pots. FINDINGS: 407 children, one per household, entered the study. The change in haemoglobin concentration was greater in the iron-pot group than in the aluminium-pot group (mean change to 12 months 1.7 [SD 1.5] vs 0.4 [1.0] g/dL; mean difference between groups 1.3 g/dL [95% Cl 1.1-1.6]). The mean differences between the groups in weight and length gain to 12 months (adjusted for baseline weight or length) were 0.6 cm (95% CI 0.1-1.0) and 0.1 kg (-0.1 to 0.3). The laboratory study showed that total and available iron was greatest in foods cooked in iron pots, except for available iron in legumes for which there was no difference between types of pot. INTERPRETATION: Ethiopian children fed food from iron pots had lower rates of anaemia and better growth than children whose food was cooked in aluminium pots. Provision of iron cooking pots for households in less-developed countries may be a useful method to prevent iron-deficiency anaemia.

Aluminum↗
PubMed1999

Risk factors for iron deficiency anaemia in preschool children in northern Ethiopia.

OBJECTIVE: To determine risk factors for anaemia in preschool children. DESIGN: A cross-sectional study. SETTING: Tigray province, northern Ethiopia. SUBJECTS: 2080 of 2373 children aged 6-60 months provided blood to assess anaemia. RESULTS: Anaemia was highly prevalent (42%) and constituted an important nutritional problem in the region. In a sub-sample of 230 anaemic children, 56% had a low red blood cell (RBC) count, and 43% had a serum ferritin of less than 12 microgl(-1) indicating that the anaemia was largely due to iron deficiency. Unlike other regions in developing countries, hookworm (0.4%) and malaria (0.0%) were rare and contributed little to the anaemia. Even though their diet lacked variety, the amount of iron consumed through cereal-based staple foods was adequate. However, the iron in these foods was not readily available and their diets were probably high in iron absorption inhibitors and low in enhancers. Dietary factors associated with anaemia included frequent consumption of inhibitors, such as fenugreek and coffee, and poor health in the child such as diarrhoea and stunting. CONCLUSIONS: Underlying causes of anaemia were lack of safe water and inadequate human waste management, maternal illiteracy and mother being ill, and having no food reserves. The root cause of these factors was poverty. The optimal control strategy for iron deficiency anaemia should have a holistic approach which includes the alleviation of poverty, the empowerment of women and the provision of a safe environment.

Anemia, Iron-Deficiency↗
PubMed1999

Estimation of direct and indirect costs because of common infections in toddlers attending day care centers.

OBJECTIVE: To describe both the direct and the indirect costs of illness in a closely followed cohort of toddlers attending day care centers (DCCs) in Québec, Canada. METHODS: Fifty-two DCCs participated in the study. Parents were invited to fill in a calendar on which they would indicate the occurrence of colds, diarrhea, and vomiting, in addition to any actions taken with respect to this occurrence. The participating parents were called biweekly to report the information. The costs reported in this article are based on a period of 6 months of follow-up. The direct costs included medication and visits to a physician whereas indirect costs included alternative care provided by a family member, a babysitter, or an employed parent who missed work. RESULTS: Two hundred seventy-three toddlers were followed from 35 to 182 days during the study period. During a 6-month period, the adjusted average costs per child for medication and consultation were $47.47 (standard deviation [SD] = 52.76) and $49.10 (SD = 51.34), respectively, whereas they amount to $11.51 (SD = 51.19) for care by a babysitter, $35.68 (SD = 94.74) for care by a family member, and $117.12 (SD = 210.29) for a parent missing work (when using opportunity cost). The overall adjusted average total costs per child incurred to the parents and society was $260.70 (SD = 301.25). CONCLUSIONS: The originality of this study was to comprehensively include all costs associated with the care of an ill child attending DCCs. Future research should aim at finding economical ways to decrease illness frequency in toddlers attending day care centers and subsequently the costs they incur.

Child Day Care Centers↗
PubMed1999

Effectiveness of a training program in reducing infections in toddlers attending day care centers.

The objective of this study was to assess the effectiveness of a hygiene program in reducing the incidence of respiratory and diarrheal diseases in toddlers attending day care centers. A randomized field trial was conducted in 52 day care centers in Quebec, Canada, between September 1, 1996 and November 30, 1997. Absences for any reasons and the daily occurrence of colds and/or diarrhea in toddlers were recorded on calendars by the educators. The number of fecal coliforms on children's hands and on educators' hands was measured during three unannounced visits. Overall, 1,729 children were followed in 47 day care centers for a total of 153,643 child-days. The incidence rate of diarrhea was considerably reduced by the effect of monitoring (IRR = 0.73, 95% CI = 0.54,0.97), and the intervention reduced the incidence rate of upper respiratory tract infections (IRR = 0.80, 95% CI = 0.68,0.93). Monitoring alone also had an important effect in reducing the level of bacterial contamination on children's and educators' hands. The results indicate that both an intervention program and monitoring alone play a role in reducing infections in children attending day care centers.

Child Day Care Centers↗
PubMed1998

Evaluation of rubella screening in pregnant women.

BACKGROUND: The rationale for rubella vaccination in the general population and for screening for rubella in pregnant women is the prevention of congenital rubella syndrome. The objective of this study was to evaluate the effectiveness of the prenatal rubella screening program in Quebec. METHODS: A historical cross-sectional study was designed. Sixteen hospitals with obstetric services were randomly selected, 8 from among the 35 "large" hospitals in the province (500 or more live births/year) and 8 from among the 50 "small" hospitals (fewer than 500 live births/year). A total of 2551 women were randomly selected from all mothers of infants born between Apr. 1, 1993, and Mar. 31, 1994, by means of stratified 2-stage sampling. The proportions of women screened and vaccinated were ascertained from information obtained from the hospital chart, the physician's office and the patient. RESULTS: The overall (adjusted) screening rate was 94.0%. The rates were significantly different between large and small hospitals (94.4% v. 89.6%). Five large hospitals and one small hospital had rates above 95.0%. The likelihood of not having been screened was statistically significantly higher for women who had been pregnant previously than for women pregnant for the first time (4.8% v. 1.4%; p < 0.001). Of the 200 women who were seronegative at the time of screening (8.4%), 79 had been vaccinated postpartum, had a positive serological result on subsequent testing or did not require vaccination, and 59 had not been vaccinated postpartum; for 62, subsequent vaccination status was unknown. INTERPRETATION: Continued improvement in screening practices is needed, especially in small hospitals. Because vaccination rates are unacceptably low, it is crucial that steps be taken to address this issue.

Canada↗
PubMed1997

Sustaining malaria prevention in Benin: local production of bednets.

Through a Benin-Canada participatory research initiative which included both Benin and Canadian non-governmental organizations, a local capacity to produce and market bednets for the prevention of malaria was developed. The development process began following a community-based assessment of local needs and skills. All materials for the manufacture and distribution of the bednets were obtained locally with the exception of the netting which was imported from Canada. The sustainability of the enterprise is enhanced by the community's recognition of the importance of malaria and the culturally acceptable practice of bednet use.

Benin↗
PubMed1996

Common-source outbreak of acute infection due to the North American liver fluke Metorchis conjunctus.

BACKGROUND: We investigated an outbreak of acute clinical illness among 19 people who ate raw fish (sashimi) prepared from the white sucker, Catostomus commersoni, caught in a river north of Montreal, Canada. METHODS: We collected epidemiological, clinical, laboratory, and serological data on 19 individuals who ate the sashimi and six who did not. Because of the suggestive clinical picture, we set out to recover helminth parasites from uneaten fish. FINDINGS: The illness consisted of persistent upper abdominal pain, low grade fever, high blood eosinophil concentrations, and raised liver enzymes. After 10 days, opisthorchild-like eggs were found in stools. Symptoms persisted for 3 days to 4 weeks without treatment, but responded rapidly to praziquantel therapy. Necropsy of golden hamsters infected with metacercariae from uneaten fish revealed adult flukes identified as Metorchis conjunctus. INTERPRETATION: We describe an acute illness caused by the North American liver fluke M conjunctus. This is a new human disease and is the first report of a common-source outbreak of an acute illness caused by liver flukes of the family Opisthorchiidae.

Adult↗
PubMed1996

Randomized controlled trial of artesunate plus tetracycline versus standard treatment (quinine plus tetracycline) for uncomplicated Plasmodium falciparum malaria in Brazil.

A triple-blind, randomized, clinical trial was undertaken in a Brazilian Amazon region to compare the effectiveness of oral artesunate (seven days, total dose = 0.75 g) plus tetracycline (seven days, total dose = 10.5 g) (AT) and oral quinine (three days, total dose = 6 g) plus tetracycline (seven days, total dose = 10.5 g) (QT) against uncomplicated Plasmodium falciparum malaria. Effectiveness was assessed by cure rates (World Health Organization [WHO]) and parasite clearance at day 2. Patients were randomized, 88 to each group. The groups had similar baseline clinical characteristics. The incidence of side effects was much higher in the QT group (82%) than in the AT group (50%) (P < 0.001). Cure rates were similar: 80% in the AT group and 77% in the QT group (P = 0.68). Parasitemia (by day 2) cleared faster in the AT group than in the QT group (98.5% versus 47.6%, respectively; P < 0.001). These results indicate that the combination of artesunate plus tetracycline is effective in the treatment of uncomplicated falciparum malaria and may provide a useful alternative to other treatment regimens.

Adolescent↗
PubMed1995

Imported malaria. Clinical presentation and examination of symptomatic travelers.

BACKGROUND: The diagnosis of malaria in nonendemic countries presents a continuing challenge. Increasing physician awareness of the variability in its clinical presentation will improve clinical management and health outcomes. METHODS: Charts of patients in whom malaria was diagnosed at two hospital-based tropical disease centers between September 1, 1980, and December 31, 1991, were reviewed. RESULTS: Of a total of 482 cases, 182 were caused by Plasmodium falciparum and 246 by Plasmodium vivax. Fifty-two patients with P falciparum malaria were hospitalized; 13 were classified as having severe falciparum malaria. Nineteen patients with P vivax malaria required hospitalization. The only death was caused by P vivax. Chemoprophylaxis was used by, or prescribed for, 46% of patients; however, of these, only half were compliant in taking their medication. Eighty-seven percent of patients with falciparum malaria presented within 6 weeks of return from travel to an endemic area. One third of patients with P vivax malaria presented more than 6 months after travel. The average time between onset of symptoms and physician contact was 6.7 days. Diagnosis was often delayed in those who sought care outside the referral center. Almost all patients had a history of fever, but only half were febrile at presentation. Presenting symptoms and signs were non-specific. Fifty percent of patients were thrombocytopenic. Other laboratory abnormalities were mild. CONCLUSIONS: Since the presentation of malaria is vague and nonspecific, the diagnosis should be considered in any appropriately symptomatic patient with a history of travel to a malaria-endemic area, and appropriate testing should be done. Up-to-date information on chemoprophylaxis should be provided to all travelers to malaria-endemic regions.

Adult↗
PubMed1995

Bayesian estimation of disease prevalence and the parameters of diagnostic tests in the absence of a gold standard.

It is common in population screening surveys or in the investigation of new diagnostic tests to have results from one or more tests investigating the same condition or disease, none of which can be considered a gold standard. For example, two methods often used in population-based surveys for estimating the prevalence of a parasitic or other infection are stool examinations and serologic testing. However, it is known that results from stool examinations generally underestimate the prevalence, while serology generally results in overestimation. Using a Bayesian approach, simultaneous inferences about the population prevalence and the sensitivity, specificity, and positive and negative predictive values of each diagnostic test are possible. The methods presented here can be applied to each test separately or to two or more tests combined. Marginal posterior densities of all parameters are estimated using the Gibbs sampler. The techniques are applied to the estimation of the prevalence of Strongyloides infection and to the investigation of the diagnostic test properties of stool examinations and serologic testing, using data from a survey of all Cambodian refugees who arrived in Montreal, Canada, during an 8-month period.

Bayes Theorem↗
PubMed1995

Compliance with antimalarial chemoprophylaxis and the subsequent development of malaria: a matched case-control study.

To determine if there is a difference in compliance with antimalarial chemoprophylaxis between febrile travelers with and without malaria, 157 patients with malaria, a history of fever, and recent travel to a malaria-endemic area were compared with 157 matched controls. Antimalarial prophylaxis had been taken by 48% of all patients. Chemoprophylaxis use was correlated with region and purpose of travel. Cases were less likely to have taken prophylaxis (53%) than controls (76%) (odds ratio = 0.35, confidence interval = 0.27, 0.73), even after controlling for region of travel, purpose of travel, and previous exposure to malaria. Chemoprophylaxis was effective in reducing malaria risk. Travel agents and health practitioners should provide all travelers to malaria-endemic areas with adequate information about chemoprophylaxis and its importance.

Adult↗
PubMed1995

Diagnosis of malaria in the febrile traveler.

To determine if clinical presentation can be used for predicting malaria infection in febrile patients with recent travel to a malaria-endemic area, 157 patients with malaria, a history of fever, and recent travel to a malaria-endemic area were compared with 157 matched controls in case-control study. Fever pattern, symptom duration, temperature, splenomegaly, and platelet count were correlated with malaria infection. These criteria, however, either singly or in combination, had low sensitivity for accurately identifying patients with malaria. Because no criterion could accurately predict the presence of malaria, it is concluded that microscopic examinations of blood for malaria parasites should be done in all symptomatic patients with a history of travel to a malaria-endemic area.

Case-Control Studies↗
PubMed1994

Modified technique for efficient detection of microsporidia.

Changes in temperature (from room temperature to 50 degrees C) and staining time (from 90 to 10 min) were evaluated as a means of improving the detection of microsporidia from stool specimens. A blinded and independent comparison of 50 known positive matched-specimen pairs by three technologists resulted in consistently easier microscopic detection. The background is clearer, and spores stain more intensely. Staining time is reduced by 80 min.

AIDS-Related Opportunistic Infections↗
PubMed1993

Screening for schistosomiasis, filariasis, and strongyloidiasis among expatriates returning from the tropics.

The clinical utility of eosinophil determinations, stool examinations, and serological studies for detection of parasitic infection was examined in an asymptomatic expatriate population by retrospective chart review. The screened population consisted of 1,605 patients attending a tropical medicine clinic. The sensitivity of eosinophil counts as a screening test for infection with filaria, schistosomes, or Strongyloides stercoralis was 38%, and its positive predictive value was 9%. A cost-efficacy analysis of the use of three diagnostic tests in screening for infection with filaria (n = 23), schistosomes (n = 34), or Strongyloides (n = 7) was performed. The use of stool examination and serological screening together had a sensitivity of 89%, at a total cost similar to that of a conventional strategy involving a stool examination and an eosinophil count, which would have picked up only 61% of our cases. In this population, eosinophil counts contribute little to the diagnostic accuracy obtained with stool examination and serological screening, and the low specificity of eosinophil counts generates high costs.

Adolescent↗
PubMed1993

Antimalarial drug utilization by women in Ethiopia: a knowledge-attitudes-practice study.

A survey was undertaken between December 1991 and February 1992 to assess the knowledge, attitudes, and practices with respect to malaria of 300 women from six randomly selected rural communities in central Ethiopia. A total of 85% were able to recognize one or more of the common symptoms of the disease; however, the modes of transmission were generally misunderstood and only 23% believed that transmission could be prevented. More women preferred to obtain antimalarials from government clinics rather than from private drug shops, mission clinics, unofficial suppliers of injections, open markets, or from leftover sources. Under-5-year-olds were identified as the most malaria-vulnerable group and given priority for treatment; severity of illness was the principal determinant in seeking treatment. Decisions about treatment were generally made jointly by both parents. Knowledge about the transmissibility of malaria decreased with increasing distance from a health unit (odds ratio: 0.48; 95% confidence interval: 0.27, 0.86). A logistic regression analysis indicated that literacy and village were the most important variables associated with knowledge about preventing malaria.

Adolescent↗