Vitamin a deficiency and anaemia in young children living in a malaria endemic district of western Kenya.

BACKGROUND: Vitamin A deficiency makes children vulnerable to infections and influences the outcome of various infections. In 1993 vitamin A deficiency was found to be a public health problem in Bungoma district of western Kenya. OBJECTIVE: To determine the prevalence of vitamin A deficiency, anaemia and malaria parasitaemia and to correlate these with haemoglobin, ferritin and acute phase response. DESIGN: A cross-sectional study. SETTING: Bungoma district of western Kenya. SUBJECTS: Three hundred and three children aged one to three years were studied. MAIN OUTCOME MEASURES: Serum retinol, haemoglobin, serum ferritin, alpha-1 acid glycoprotein, C-reactive protein and malaria parasite density. RESULTS: Twentynine percent of the children had severe vitamin A deficiency, 92% had anaemia (haemoglobin less than 10 g/dl) 24(7%) of these were severely anaemic while 76% had malaria parasitaemia. There was no significant difference in the retinol levels of children with malaria parasitaemia and those without malaria parasitaemia (P = 0.6). Retinol levels were significantly lower among children with high C-reactive protein (P < 0.001). Malaria parasitaemia negatively correlated with haemoglobin (r = -0.13, P < 0.05) and C-reactive protein (r = 0.21, P < 0.01). There was no difference in haemoglobin level of children with normal serum retinol and those with low serum retinol (P = 0.16). Ferritin did not differ significantly among children with normal haemoglobin and those with low haemoglobin (P = 0.13). CONCLUSION: Vitamin A deficiency and anaemia are a public health problem among the children studied. The high prevalence of vitamin A deficiency may have resulted from acute phase response induced by infections.

Vitamin A deficiency in pre-school children in Kenya.

OBJECTIVE: To determine the prevalence of vitamin A in pre-school children in Kenya. DESIGN: Cross-sectional survey. SETTING: Fourteen districts randomly selected from the eight provinces in Kenya. SUBJECTS: Six thousand four hundred and twenty five pre-school children (3298 boys and 3127 girls) aged 6-72 months in 27 clusters randomly selected from fourteen districts. MAIN OUTCOME MEASURES: Serum retinol levels and xerophthalmia were determined using High Pressure Liquid Chromatography (HPLC) and ophthalmological assessment respectively. RESULTS: The mean serum retinol was 0.84 mmol/l +/- 0.58 SD. The mean serum retinol by sex was 0.82 +/- 0.51 SD and 0.87 +/- 65 SD (p=0.005) for boys and girls respectively. Over seven per cent of the children were severely vitamin A deficient (<0.35 mmol/l) and 32.9% had marginal vitamin A deficiency (0.70 mmol/l). In the age group six to eleven months, 11.2% and 40.7% of the children were severely and marginally vitamin A deficient, respectively. Clinical examination results indicated that 0.1% of children had corneal xerosis (X2), and one per cent of the children had Bitot's spots (XIB). Geographically, the results show that the problem is most prevalent in Kwale, Mombasa, Kitui, Baringo, Kisumu, Kisii, Bungoma, Garissa and Mandera. CONCLUSION: This survey demonstrated that regardless of the assessment method used, vitamin A deficiency is a significant public health problem in Kenya which requires urgent interventions. The group at highest risk was children aged six to twenty three months. Boys were at more risk than girls.

Prevalence of malnutrition in Kenya.

BACKGROUND: Prevalence of malnutrition among pre-school children can be used to determine the need for nutrition surveillance, nutritional care, or appropriate nutritional intervention programmes. Such data also indicate the target groups and where interventions are required. OBJECTIVE: To determine the at risk groups, extent and magnitude, and regional distribution of malnutrition. DESIGN: A cross sectional study. SETTING: The survey was conducted in 14 districts representative of the eight provinces of Kenya. SUBJECTS: Six thousand, four hundred and nineteen children (3294 males and 3125 females) aged six to 72 months selected using the cluster sampling technique from eight provinces were studied. MAIN OUTCOME MEASURES: Anthropometric measures of height/length and weight were used to do the assessment. RESULTS: The prevalence of stunting, wasting and underweight were 37%, 6% and 27% respectively. Stunting was highest among the 12-23 months age group (44.8%). A statistically significant difference (p = < 0.005) was found between boys and girls with regard to stunting. This difference was more remarkable when the two were stratified by age group where 29% of the boys were stunted compared to 20% of the girls. Geographically, it was found that there exists great regional disparities with a low (22.6%) in Kiambu and a high (56.5%) in Kwale districts. CONCLUSION: These results show that malnutrition is still a serious public health problem in Kenya and requires urgent attention. The problem since the first survey in 1977 shows an upward trend, suggesting deterioration over the years. Well thought out and targeted intervention programmes are long overdue. The results of this survey and others emphasize the importance of having a well established surveillance system which would ensure necessary and timely action.

PIP: This cross-sectional study examined the prevalence, severity, regional differences and age-sex distribution of malnutrition in Kenya. About 6419 children (3294 males and 3125 females) from 14 districts in Kenya were examined using two anthropometric measurements: weight and height. The three nutritional status indicators used were stunting, wasting, and underweight, with an overall prevalence of 36%, 6%, and 27%, respectively. Findings indicated that stunting was lowest among the 6-12 month age group and highest among the 12-23 month age group, with a prevalence 15 times higher among boys. On the other hand, both growth stunting and wasting were most serious between 12 and 23 months of age, similar to previous reports. The most pressing form of malnutrition in Kenya is protein-energy malnutrition, which largely affects infants, preschool, and school children. Regional disparities in malnutrition were also observed, with a low malnutrition rate in Kiambu (22.6%) and a high malnutrition rate in Kwale (56.5%) districts. This study, as well as the results of previous findings, confirms the seriousness of malnutrition in Kenya. This paper suggests the implementation and development of monitoring and evaluation mechanisms to assess the impact of implemented program activities, particularly in districts with high malnutrition rates.

Predictors of low birthweight at the community level.

The outcome of pregnancy was studied in 148 women over a two year period in a rural area of Kenya as part of a prospective longitudinal study whose main objective was to study the functional effects of mild to moderate malnutrition. Data were collected on maternal anthropometric variables monthly, haemoglobin levels were determined by blood samples taken every six months, food intake was based on two days each month of actual weight and recall. Each woman's past reproductive history was established at the beginning of the study. Birth weight was taken and recorded within seventy two hours of delivery. Discriminant analysis was used to identify predictors of low birthweight. The analysis was based on 123 cases who had complete data on all the variables used in the equation. Of those included in the analysis, 14 women (11%) delivered low birthweight babies and 109 had normal birthweight babies. Results of the discriminant analysis showed that mid upper arm circumference (MUAC), body mass index (BMI), Blood haemoglobin levels (HB) and socioeconomic status (SES), are the best predictors of low birthweight. Ranked in order of relative contribution to birthweight they are BMI, HB, MUAC and SES. Low birthweight prevalence was determined as being 11.2 per cent. Eighty per cent of all known cases were correctly classified using the four variables. As a screening tool for low birthweight this model with four variables has 93% sensitivity, 78.4% specificity, 35.13% positive predictive value and 98.98% negative predictive value. The results suggest that it is possible to identify women at high risk for delivering low birthweight babies at the community level.

Evaluation of the QBC method to detect malaria infections in field surveys.

The conventional peripheral blood film method used to diagnose malaria is characterized by low sensitivity in scanty parasitaemia and can be time consuming when required to rule out infection. The Quantitative Buffy Coat (QBC) method has been proposed to be quicker and more sensitive. We conducted a malaria survey in April 1992 among school-children in Kisumu (holoendemic) and Webuye (hypoendemic) areas of Western Kenya. Peripheral blood samples were examined by thick blood smear (TBS) stained with Giemsa solution, and by the QBC method. A total of 360 paired samples were analyzed. There were 175 (49%) positive TBS and 201 (56%) positive QBC. Of the 185 TBS classified as negative, 30 (16%) were positive by QBC. When parasite density by TBS was > or = 100/300 WBCs, the sensitivity of QBC was 100%. Overall sensitivity for QBC was 98%, with a specificity of 84%. Negative predictive value for the QBC was 98%, and had a calculated accuracy of 92%. It took an average of 44 minutes to process a TBS and a further average of 2.6 minutes to examine a negative TBS. For the QBC the mean time to process and to examine was 7.09 and 1.04 minutes respectively. We conclude that the QBC is quicker, with high sensitivity, and will prove useful in clinical and epidemiological screening, especially when parasitaemia is low.

The effect of permethrin impregnated sisal curtains on vector density and malaria incidence: a pilot study.

Impregnation of bednets and curtains with suitable pyrethroids may reduce entomological inoculation rates (EIR) and malaria incidence. We conducted a quasi-experimental pilot study over 3 months in Western Kenya on 20 houses with 54 children. Ten houses in the experimental site received sisal curtains treated with permethrin at either 0.5g/m2 or 0.1g/m2. Control houses had untreated curtains or none. Mosquito vector density (MVD), man biting rates (MBR), and residual insecticidal effects (RIE) of permethrin were determined every two weeks. MVD was reduced by 97.7% and 98.7% in houses from the 2 experimental groups with a 60% reduction with unimpregnated curtains. MBR varied from 6.4 (no curtains), 1.7 (unimpregnated), 0.7 (0.5g/m2 curtains) to 0.4 (1.0g/m2 curtains). RIE begun to decline after the fourth month. Malaria incidence remained similar at the two sites. We conclude that covering of eaves and windows with permethrin impregnated sisal curtains can reduce MVD and the number of mosquito bites to individuals sleeping in protected houses.

The effect of permethrin impregnated sisal curtains on vector densities and malaria incidence: a pilot study

Malaria is a major public health problem in the tropics and sub-tropics and has been shown to be a major cause of days of healthy life lost. Impregnation of bednets and curtains has been reported to reduce vector inoculation rates and malaria incidence. We conducted a qausi-exiperimental pilot study for three months in western Kenya on 20 houses with 54 children. 10 houses in the control area received either no sisal curtains or unimpregnated curtains while 10 others in the experimental site received impregnated curtains but at different concentration levels viz:0.5 g/m2 and 1.0 g/m2). Vector densities and man biting rates were monitored once every two weeks using the spray sheet collection and the human bait catches. Bioassays using the standard WHO cone-method were done fortnightly. Malaria morbidity was monitored among the 54 children (22 in control and 32 in experimental) fortnightly by taking blood smears and temperature. In houses with impregnated curtains at 0.5 g/m2 vector densities were reduced by 97.7 while in the houses with 1.0 g/m2 the density reduction was 98.7. A 50 reduction was also observed in houses with unimpregnated curtains. On average man biting rates in houses with no curtains were 6.4 bites per man per night. In the houses with curtains the average bites per man per night were 1.7 (unimpregnated); 0.7 (0.5 g/m2curtains) and 0.4 (1.0 g/m2curtains). All mosquitoes exposed toimpregnated curtains (at both concentration levels) died; up to the fourth month;aftre which therewas decline in residual effect. There was no significant difference in malaria incidence at the two sites. We conclude that covering for eaves and windows with permethrin impregnated sisal curtains can reduce mosquito densities in the houses as well as the number of mosquito bites to individuals sleeping in those houses