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A R Wickremasinghe

Publications and source records attributed to A R Wickremasinghe.

30 records · Page 2Linked to original sources

Clinical diagnosis of uncomplicated malaria in Sri Lanka.

To assess the possibility of developing a protocol for the clinical diagnosis of malaria, a study was done at the regional laboratory of the Anti-Malaria Campaign in Puttalam, Sri Lanka. Of a group of 502 patients, who suspected they were suffering from malaria, 97 had a positive blood film for malaria parasites (71 Plasmodium vivax and 26 P. falciparum). There were no important differences in signs and symptoms between those with positive and those with negative blood films. It is argued that it is unlikely that health workers can improve on the diagnosis of malaria made by the patients themselves, if laboratory facilities are not available. For Sri Lanka the best option is to expand the number of facilities where microscopic examination for malaria parasites can take place.

Adolescent↗

Optimizing the malaria data recording system through a study of case detection and treatment in Sri Lanka.

The potential of using malaria incidence data routinely collected from endemic regions for disease control and research has increased with the availability of advanced computer-based technologies, but will depend on the quality of the data itself. We report here an investigation into the relevance of malaria statistics provided by the routine data collection system in Moneragala, a rural malaria-endemic region in Sri Lanka. All patients (n = 321) treated for malaria in 2 clusters of health care centres (HCCs) of both the private and the public sector in the administrative regions of Moneragala and Buttala Divisional Secretariat (D.S.). Divisions were studied in December 1995/ January 1996. The catchment area of these HCCs included a population resident in 53 Grama Niladhari (GN) areas, the smallest administrative units of the country. Almost equal numbers of malaria patients were detected and treated at Government and private health care institutions, and in 70% of them treatment was based on a diagnosis confirmed by microscopy. The routine data recording system, however, included only statistics from the Government sector, and only of patients whose diagnosis was microscopically confirmed. In compiling data, the origin of a case of malaria is attributed to the D.S. Division in which the institution (at which the patient was treated) was located, rather than the area in which the patient was resident, which was inaccurate because 90% of malaria patients sought health care at institutions located closest to their residence, thus crossing administrative boundaries. It also led to a loss of resolution of spatial data because patients' addresses recorded at the Government HCCs to the village-level are replaced in the statistics by the D.S. Division, which is a coarse spatial unit. Modifications to the system for malaria case recording needed to correct these anomalies are defined here. If implemented, these could result in major improvements to the quality of data, a valuable resource for the future of malaria control. The paper reiterates the call for the use of a standard spatial unit within a country to facilitate exchange of data among health and other sectors for the control of tropical diseases.

Data Collection↗

Early diagnosis and treatment of malaria in a refugee population in Sri Lanka.

To provide early diagnosis and prompt treatment for malaria, two interventions were compared in refugee camps in Kalpitiya, Sri Lanka. Community health volunteers (HV's) were trained in diagnosis and management of malaria on clinical grounds, while a field laboratory was established in another group of camps providing treatment after laboratory confirmation of a malarial infection. Patients with fever sought treatment from HV's on average after 2.74 days and from the field laboratory after 3.20 days. Although acceptance of both interventions was high, the effective catchment areas, especially of the HV's were small. Large numbers of health volunteers would be needed to cover all families, making it difficult to sustain supervision and necessary logistic support. For every malaria patient treated by HV's, three others would receive anti-malarial drugs unnecessarily. The maintenance of a field laboratory with a microscopist of the Anti-Malaria Campaign is not an economically viable option. Training of HV's in microscopy with a mechanism for cost recovery should be given serious consideration. HV's and diagnosis and treatment centers should be able to handle a wide spectrum of common diseases. A better option for Sri Lanka in the short term might be to improve existing general health facilities that are accessible to the refugee population.

Adult↗

Development of the VIIIth nerve compound action potential evoked by low-intensity tone pips in the Mongolian gerbil.

Maturation of the cochlea and afferent auditory units is reflected by changes in VIIIth nerve compound action potential (CAP) parameters. We studied auditory nerve CAPs evoked by low-intensity stimuli in Mongolian gerbils (Meriones unguiculatus) ranging in age from 22 to 92 days after birth. The gerbil CAP development is characterized by marked changes in latency, threshold, and amplitude during the first few weeks of life. CAP latency and CAP threshold reach adult-like values at about 1 month of age. In contrast, the CAP amplitude continues to grow in size even after 2 months. This dichotomy suggests that the development of afferent auditory nerve function in the gerbil is preceded by maturation of the mechanical processes of the middle ear and cochlea.

Acoustic Stimulation↗

Development of contralateral suppression of the VIIIth nerve compound action potential (CAP) in the Mongolian gerbil.

We studied whether same-frequency contralateral tones of 65 dB pSPL (peak Sound Pressure Level) suppress the VIIIth nerve compound action potential (CAP) evoked by 40-45 dB pSPL tone pips in the Mongolian gerbil from 22 to 92 days after birth (DAB). The primary stimuli were tone pips of 1, 2, 4, 8, and 10 kHz; only the 1 kHz CAP amplitude was suppressed significantly by tones of the same frequency. The suppression was seen at 22 DAB, and underwent little relative change with development.

Acoustic Stimulation↗

Testing specific hypotheses by fitting underlying distributions to categorical data.

The problem of estimating parameters and testing hypotheses pertaining to categorical data is well known in statistical analysis. Much of the literature on the subject specifies and fits linear models to multinomial data using methods such as weighted least squares. This article describes maximum-likelihood estimation and likelihood ratio tests for ordered categorical response variates with either discrete or continuous underlying probability distributions. Emphasis is on fitting and making inferences about parameters of mixture distributions, especially mixtures of normal distributions. Goodness-of-fit tests are given to check the adequacy of the fitted distributional models.

Data Interpretation, Statistical↗

Adolescent pregnancy: maternal weight effects on fetal heaviness: possible route to improved outcomes.

In a previous report of a zinc supplementation trial in pregnant adolescents zinc effect varied according to maternal weight (wt) status--normal (90-110% of expected wt), light or heavy, prompting this analysis of effects of wt status and gestational wt gain on fetal heaviness relative to length and gestational age (GA) and other pregnancy outcomes. One-third of adolescents shifted in or out of normal wt by delivery, creating seven outcome groups--light-light, light to normal, normal to light, normal-normal, normal to heavy, heavy to normal, and heavy-heavy. These wt class change groups varied significantly as to intrauterine growth (SGA, low AGA, high AGA, and LGA); by weekly grams gain per cm height (ht), birth wt, infant wt/length ratio, and occurrence of low birth wt (LBW). Infants with above average intrauterine growth had an advantage in: absolute size, length of hospital stay, rates of LBW, fetal demise, rates of low Apgar score, and "other" complications. This association between intrauterine growth and maternal wt class change suggests that promotion of wt gain might lower rates of LBW. Birthwt varied by quartiles of weekly wt change (gm) per cm ht in women grouped by their percent of expected wt: in the lowest quartile (Q1) only one group in seven reached average Bwt (3025 grams); with Q4 gain all groups did. Thus, the parameter wt gain/wk/cm ht deserves study as a tool for monitoring wt status and gain to identify those pregnant adolescents in greatest need for nutritional counseling and to set wt gain goals.

Adolescent↗

Anthropometric indicators of children's nutrition in two Nigerian communities.

On a sample of some 2000 children living in two ecologically different zones (the Wooded and Guinea savanna) in Kwara state, Nigeria, body measurements were taken, to serve as indicators of the state of nutrition. There was more undernutrition in the Guinea savanna than in the Wooded. More males than females were undernourished in the Guinea savanna but not in the Wooded. It is argued that the differences between districts stem from social and cultural variables.

Adolescent↗

Birthweight and sociobiological factors in Ilorin, Nigeria.

Social and biological factors influencing birthweight of 3053 Ilorin babies were studied. The mean birth weights were 2.998 kg +/- 0.133 (SD) for males and 2.932 kg +/- 0.154 (SD) for females. Multiple regression analysis showed that maternal weight, height, age, education and ethnicity, and child's sex, significantly affected birthweight of infants. Some quadratic and interaction terms also contributed significantly to the prediction of birthweight. The strategies to control the incidence of low birth weight are discussed.

Birth Weight↗

Cognitive performance at school entry of children living in malaria-endemic areas of Sri Lanka.

In a cross-sectional study, carried out in January 1997 at the beginning of the school year, the impact of repeated attacks of malarial infection on the cognitive performance of children at school entry in moderate malaria-endemic areas of Sri Lanka was investigated. The cognitive performance of 325 schoolchildren in grade 1 (mostly aged 5-6 years) in 2 districts of Sri Lanka which are endemic for malaria (Anuradhapura and Moneragala) was assessed by an entry performance test developed by the National Institute of Education, Sri Lanka. The indices assessed included writing, language and mathematical skills. There was no difference in any of the cognitive performance indices between children from Anuradhapura and Moneragala districts. The scores of most of the indices decreased as the number of malaria infections experienced by a child increased and the ability to identify letters was significantly impaired by the number of malaria infections a child had experienced after controlling for socio-economic and nutritional status. These findings suggests that repeated attacks of malaria in children can have an adverse impact on their development.

Child↗