PubMed Health⌕ Search

Biomedical subjects

L S Stephenson

Publications and source records attributed to L S Stephenson.

53 records · Page 3Linked to original sources
PubMed1982

Intestinal parasitic infections of men in four regions of rural Kenya.

Faecal samples were obtained from 906 men living in four different regions of rural Kenya: the cool Highlands, the humid coastal lowlands, the equatorial Lake Victoria basin and the arid marginal highlands. The prevalence of intestinal parasitic infections is reported and compared, contrasted and discussed in terms of the typical environmental conditions in each region. Almost 70% of men appeared to be infected with intestinal helminths; hookworm was most common. The regional prevalence of hookworm infections appeared to be related to relative humidity.

Environment↗
PubMed1982

A comparative study of the nutritional status, parasitic infections and health of male roadworkers in four areas of Kenya.

The nutritional status, parasitic infections and general health of 801 male roadworkers living in four different areas of Kenya, namely, the highlands, coastal lowlands, Lake Victoria basin and the semiarid north-west, were investigated. Undernutrition was common in all areas but was most marked among men in the semi-arid area. Anaemia was most prevalent in the coastal lowlands where 41% of men had a haemoglobin level less than 13.0 g/dl. Hookworm eggs were seen in the faeces of 40% of all men and in 69% of samples collected in the coastal lowlands. The Lake Victoria basin was a significant focus of infection with Schistosoma mansoni, 51% of faecal samples containing its eggs; S. haematobium also occurred but was most common in the coastal lowlands. Stages of Plasmodium spp. were most commonly observed in blood smears collected from men near Lake Victoria and the coast, two significant foci of malaria. An analysis of variance was used to examine the relationship between variables and indicated that the most significant association was between hookworm infections and low haemoglobin levels.

Adult↗
PubMed1981

Taenia saginata (Cestoda) in western Kenya: the reliability of faecal examinations in diagnosis.

The prevalence of Taenia saginata (Cestoda) among 146 predominantly Pokot tribesmen in western Kenya was studied in an attempt to assess the reliability of detecting infections by faecal examinations. firstly, a single faecal sample was microscopically examined after being processed by a standard ether sedimentation technique. Secondly, all subjects were treated with niclosamide and a purgative and the tapeworms were recovered. In this way the efficiency of diagnosing infections by faecal examinations was estimated. T. saginata eggs were found in the faeces of 68% of the men who were eventually found to be infected. Information was collected by interview from all subjects about whether they were or ever had been infected with tapeworms and about the form of treatment previously sought or taken. Eleven out of 25 men were apparently unaware of their tapeworm infections while no evidence of infection was found among 10 of the 24 reportedly infected men. A change in the pattern of treatment for tapeworms was reported which may have resulted in a recent decline in the prevalence of infection.

Adult↗
PubMed1980

The contribution of Ascaris limbricoides to malnutrition in children.

There is a need for more applied and experimental research to determine more precisely the relationships between nutrition, particularly childhood malnutrition, and intestinal parasitic infections, particularly Ascaris infection. Nevertheless, it is clear that in certain communities Ascaris infection is associated with poor growth in malnourished children and that deworming improves growth. Periodic deworming of children using a mass treatment approach may be needed to control soil-transmitted helminths in areas where parasites and protein energy malnutrition are highly prevalent. The main aims of treatment should be to reduce parasite loads below the level of clinical significance for the individual child and to reduce future environmental contamination with infective faeces for the sake of the community.

Animals↗
PubMed1980

Relationships between Ascaris infection and growth of malnourished preschool children in Kenya.

A longitudinal study in Ascaris-infected and noninfected children was conducted in two Kenyan villages. Anthropometric, clinical, and stool exams were performed three times at 14-week intervals. All children received an anthelmintic drug (levamisole) at the second examination. In the 14 weeks before deworming, children with Ascaris (n = 61) did not differ from controls (n = 125) in percentage expected weight gain. In the 14 weeks after deworming, previously infected children showed higher percentage expected weight gain than controls. Before deworming, there was a statistically significant (P less than 0.0005) decrease in triceps skinfold thickness in Ascaris-infected children versus controls. After deworming, skinfold increased significantly (P less than 0.0005) in previously infected children versus controls. Multiple regression analysis showed that Ascaris infection was by far the most important variable of those studied explaining decrease in skinfold thickness before and increase after deworming. It appears that even light Ascaris infections might adversely influence nutritional status, and deworming might enhance growth.

Anthropometry↗
PubMed1977

Milk consumption by black and by white pupils in two primary schools.

It is heartening to note that relatively well nourished black children in the United States, a number of whom are, in all probability, lactose intolerant and most of whom are destined to become lactose intolerant adults, are able to consume nutritionally valuable quantities of milk with meals and, on the whole, do not report suffering from any abdominal pain or discomfort. It is also encouraging that this population of over two hundred primary school children consumed, on the average, 75 per cent of the 1/2 pt. milk served with lunch, reported drinking an average of three glasses of milk daily, and the vast majority reported liking milk and a number of other dairy products which are important nutrient sources in their diets.

Adolescent↗
PubMed1977

Infection of weanling pigs with known numbers of Ascaris suum fourth stage larvae.

Nineteen weanling pigs were each infected per os with 200 fourth stage Ascaris serum larvae and were fed either a low protein or a high protein diet for 8 weeks. Worms expelled during the 8 weeks were recovered and all worms remaining in the gastrointestinal tract at slaughter were collected. Fifty-four percent of all worms were recovered at slaughter. Ten of the 19 animals maintained an infection for 8 weeks; the other 9 showed no signs of A. suum infection. A total of 377 worms were recovered. Average worm burdens were 37.7 worms per pig, 50.8 worms per low protein pig, and 30.8 worms per high protein pig. Times of and possible causes for expulsion are discussed. Procedure for infection of pigs is discussed in detail and possible improvements in technique are suggested.

Animals↗
PubMed1975

Rapid and portable methods of lactose tolerance test administration.

Abbreviated, portable methods of lactose tolerance test administration were investigated. Results obtained with the Ames Reflectance Meter/Dextrostix system for blood glucose determination during lactose tolerance testing were compared with those obtained from a standard method, the AutoAnalyzer. Subjects who had maximum blood glucose rises below 20 mg/100 ml were considered to have a flat lactose tolerance curve and were designated lactose nondigesters. Results of the two methods were very similar for determination of maximum rise in blood sugar over fasting level, for obtaining values of individual blood sugar determinations, and for diagnosis of lactose nondigesters. The effect of omission of the final blood sample on tolerance test results was examined. It was found that maximum rises in blood glucose occurred before the final sample in 31 of 35 cases on the AutoAnalyzer and in 26 of 27 cases on the Reflectance Meter. In no case did omission of the final sample change the results of the lactose tolerance test.

Adult↗
PubMedDate not supplied

Improvements in physical fitness of Kenyan schoolboys infected with hookworm, Trichuris trichiura and Ascaris lumbricoides following a single dose of albendazole.

We studied physical fitness with the Harvard step test (HST), in primary schoolboys infected with hookworm (91% baseline prevalence), Trichuris trichiura (94%) and Ascaris lumbricoides (39-40%) who received a single 400 mg dose of albendazole or an identical placebo. Boys were examined, allocated at random to placebo or albendazole groups, treated, and re-examined 7 weeks later. The 2 groups did not differ significantly before treatment in age, anthropometry, haemoglobin levels, prevalence or intensity of the 3 helminth infections, or in initial HST fitness scores and heart rates. Seven weeks after treatment, the albendazole group (n = 18) exhibited significant improvements in fitness scores and heart rates at 1, 2, 3, and 4 min after the HST while in the placebo group (n = 15) these quantities had not changed significantly. After treatment, the albendazole group had significant decreases in the logarithmic egg counts for hookworm (80% reduction in arithmetic means) and A. lumbricoides (100% reduction); T. trichiura egg counts did not change significantly. The placebo group showed a borderline increase in the logarithms of hookworm egg counts and no significant change in T. trichiura and A. lumbricoides egg counts. Multiple regression analysis showed that the significant linear predictors of increase in HST score after treatment were decrease in resting heart rate after treatment, and decreases in hookworm egg counts and logarithms of A. lumbricoides egg counts after treatment. We conclude that single dose treatment with albendazole, despite continual exposure to reinfection, can allow improved physical fitness in schoolboys in areas where soil-transmitted helminths and protein-energy malnutrition are highly prevalent.

Albendazole↗
PubMedDate not supplied

The use of human faeces for fertilizer is associated with increased intensity of hookworm infection in Vietnamese women.

To investigate different factors associated with hookworm infections we conducted 2 studies in a commune in northern Viet Nam. The first was part of a larger study on anaemia and covered 213 women (15-49 years of age) and their 92 children (6 months to 5 years of age) in one commune; 90% of the families reported using human faeces for fertilizer. Women who reported using fresh human faeces as fertilizer had significantly higher hookworm egg counts than women who either used treated human faeces or who did not use human faeces as fertilizer. The second study examined how human faeces were used for fertilizer in 30 selected families. Women participated in preparation and application of human faeces to crops in 81% of the families using human faeces for fertilizer. Two methods of preparing the faeces were described: 48% of the families mixed the faeces with ash before applying them to the field; 18% mixed the faeces with water; 33% used both methods.

Adolescent↗
PubMedDate not supplied

Improvements in growth following iron supplementation in young Kenyan school children.

The study was conducted to determine whether provision of oral supplementary iron to primary school children in Kenya would improve their growth. Children in the two lowest grades who satisfied study criteria were allocated to either an iron-supplementation group (n = 29) or a placebo group (n = 26). At the baseline before intervention the groups did not differ significantly in age, sex ratio, prevalence and intensity of intestinal helminthic infections, most anthropometric measurements or hemoglobin levels. Although the study lasted for 32 weeks, children only took iron or placebos on school days thus omitting weekends and school holidays. Examination at the end of the study showed that the iron-supplemented children had grown significantly more in terms of weight, weight for height, arm circumference and skinfold thickness compared with the placebo group. Hemoglobin levels had also improved significantly. We conclude that where iron deficiency anemia and undernutrition are prevalent in children, iron supplementation will improve growth and hemoglobin levels.

Anemia, Hypochromic↗