Prevalence of trachoma in six districts of Kenya

OBJECTIVES

To estimate the prevalence of active trachoma (TF) in children aged one to nine years and potentially blinding trachoma (TT) in adults aged 15 years and older in six known trachoma-endemic districts in Kenya.

DESIGN

Community based survey.

SETTING

Six known trachoma endemic districts in Kenya (Samburu, Narok, West Pokot, Kajiado Baringo and Meru North).

SUBJECTS

A total of 6,982 children aged one to nine years and 8,045 adults aged 15 years and older were randomly selected in a two stage random cluster sampling method: Twenty sub-locations (clusters) per district and three villages per sub-location were randomly selected. Eligible children and adults were enumerated and examined for signs of trachoma.

RESULTS

Blinding trachoma was found to be a public health problem in all the surveyed districts. Active trachoma was a district wide public health problem in four districts (Samburu, Narok, West Pokot and Kajiado) and only in some of the sub-locations of the other two (Baringo and Meru North).

CONCLUSIONS

There is need for district trachoma control programmes preferably using the WHO recommended SAFE strategy in all the surveyed districts. Extrapolation of these survey results to the entire country could not be justified. There is need to survey the remaining 12 suspected endemic districts in Kenya.

Gender equity and trichiasis surgery in the Vietnam and Tanzania national trachoma control programmes

AIMS

To calculate the gender distribution of trichiasis cases in trachoma communities in Vietnam and Tanzania, and the gender distribution of surgical cases, to determine if women are using surgical services proportional to their needs.

METHODS

Population based data from surveys done in Tanzania and Vietnam as part of the national trachoma control programmes were used to determine the rate of trichiasis by gender in the population. Surgical records provided data on the gender ratio of surgical cases.

RESULTS

The rates of trichiasis in both countries are from 1.4-fold to sixfold higher in females compared to males. In both countries, the female to male rate of surgery was the same or even higher than the female to male rate of trichiasis in the population.

CONCLUSIONS

These data provide assurance of gender equity in the provision and use of trichiasis surgery services in the national programmes of these two countries. Such simple analyses should be used by other programmes to assure gender equity in provision and use of trichiasis surgery services.

Costs of tuberculosis for households and health care providers in Dar es Salaam, Tanzania

OBJECTIVE

To assess the costs of tuberculosis at household level in Dar es Salaam and to compare them with the provider costs of the national tuberculosis control programme.

DESIGN

Tuberculosis patients were found by active case searching within a routine census in three areas of Dar es Salaam, and by examining records for residents already receiving treatment. Costs at household level were evaluated through a cross-sectional household survey.

RESULTS

One hundred and ninety-one tuberculosis cases were included in the survey. With treatment periods of 8 to 12 months, extrapolated average costs of a period of illness to patients and their families were as follows: US 2 dollars for examination and laboratory costs, between US 17 dollars and US 50 dollars for consultation and drugs, less than US 1 dollar for hospitalization and between US 13 dollars and US 20 dollars for transport. The analysis revealed high costs due to inability to work, ranging from US 154 dollars to US 1384 dollars. These data were compared with the operation costs of the tuberculosis programme and proved to comprise 68% to 94% of total costs.

CONCLUSIONS

For patients and their families, tuberculosis implies three main types of cost: drugs, transportation and, most importantly, financial loss due to inability to work. They represent around two thirds of total cost and are a high economic burden for households, in particular those with a low-income. While assessing tuberculosis control strategies such as direct case finding at home, it is therefore important to also include costs incurred at household level.

The population biology and epidemiology of schistosome and geohelminth infections among schoolchildren in Tanzania

A study of helminth infections was undertaken among 3244 schoolchildren from 28 schools in Morogoro Rural District, Tanzania. Schistosoma haematobium was the most common infection, followed by hookworms, Ascaris lumbricoides, S. mansoni, and Trichuris trichiura. Infection prevalence of each species varied among schools and age groups, but not between sexes. There was no relationship between the prevalences of different infections among schools, except for a strong negative correlation between the prevalence of hookworm and S. mansoni infections. Within each age group, there was little excess overlap in the distribution of each infection; thus the number of multiple infections was low whereas the number of individuals harbouring at least one infection was relatively high. More children than expected carried infections of A. lumbricoides and S. mansoni, and the clustering effect increased with age. Only 2 schools had high overall infection prevalences of both geohelminths and schistosomes. Logistic regression analysis of morbidity and parasitological data indicated that individuals with multiple species infections were not at increased risk of morbidity (on a multiplicative scale) compared to individuals with single species infections. This was attributed in part to the low egg counts observed for each parasite species. The results implied little interaction between schistosome and geohelminth infections in the region, both in parasitological terms and in the context of their combined effects on health. Implications for the feasibility and benefits of combined control of geohelminths and schistosomes are discussed.

The use of morbidity questionnaires to identify communities with high prevalences of schistosome or geohelminth infections in Tanzania

Parasitic infections were investigated in Morogoro Rural District, Tanzania, between October 1992 and June 1993. A total of 4589 schoolchildren (aged 7-17 years) from 30 primary schools was screened for infection with Ascaris lumbricoides, Trichuris trichiura, hookworms (3456 children only), Schistosoma mansoni and S. haematobium. The children were also asked about their recent experiences of the following: diarrhoea, abdominal pain, blood in stool, perception of suffering from schistosomiasis, and worm infection and examined for spleen and liver enlargement. Among schools, there were correlations between the prevalence of S. mansoni infection and bloody stools, spleen enlargement and liver enlargement, and between S. haematobium infection and the presence of blood in urine. To exclude ecological explanations for the correlations, logistic regression was used to estimate the adjusted odds ratio (OR) for each infection and each sign or symptom. No sign or symptom was significantly associated with any geohelminth infection. Reported blood in stool was significantly associated with S. mansoni infection (OR = 1.62, P = 0.045). Reported blood in urine was significantly associated with S. haematobium infection (OR = 7.71, P < 0.001), as was reported blood in stool (OR = 11.52, P < 0.001), indicating that presence of blood in either form of excreta was related to the local term for schistosomiasis. These results support the possibility of using reported blood in stool as a means of rapid assessment for identifying communities with a high prevalence of S. mansoni infection.

Utilisation of government and private health services in Dar es Salaam

Following the liberalisation of medical practice in Tanzania since the early 1990's, and the introduction of user fees in public hospitals in 1993, a household survey evaluated utilisation of health care in Dar es Salaam. A sample of 6,589 inhabitants was interviewed in April 1995 by means of a two-stage cluster sampling technique. Of the respondents, 32% reported some use of health care within the previous two weeks. Among these respondents, 35% had used government health services, 41% had used private services and self-treatment was chosen by 27%. The user patterns identified reveal that adults aged 15-49 years used government health service least often. Use of government services clearly decreased as the level of education, socioeconomic class and wealth status of the zone of residence of the ill person increased. Conversely in the study sample, there was an apparent tendency for people with a high level of education or belonging to a rich socio-economic class to use private facilities more often. The data also indicate that already after two years the private sector plays an important role in providing medical care and that a two-tier system of health care delivery is developing. In order to render the private sector complementary to public services, there is need for a coherent policy on legislation, development, regulation and control of private sector health services as well as a monitoring system to reinforce the policies.

Validation of reagent sticks in diagnosing urinary schistosomiasis in an urban setting

In view of the established potential of reagent sticks for detecting haematuria, a pilot survey to validate their use in the diagnosis of urinary schistosomiasis in an urban setting was done at Kinyerezi primary school of Ilala district in Dar es salaam. From 404 pupils screened for the disease, 273 were positive for the eggs by microscopy (filtration method), giving a prevalence of 67.6% and 253 (92.6%) of those who were positive by microscopy were also positive for haematuria by reagent sticks. Out of 131 who had no disease, 113 (86.2%) were negative for haematuria by the reagent sticks. These findings indicate a high sensitivity and specificity of microhaematuria by the reagent sticks (92.6% and 86.2%) respectively. Taking microscopy as a standard test, macrohaematuria had a sensitivity and specificity of 40.6% and 90% respectively, for urinary schistosomiasis. The accuracy of microhaematuria by reagent sticks was 90% compared to macrohaematuria which was only 56.6%. The use of reagent sticks test in detecting microhaematuria is thus recommended as a valid and rapid diagnostic test for urinary schistosomiasis in the present setting.

Quality of primary outpatient services in Dar-es-Salaam: a comparison of government and voluntary providers

This study aimed to test whether voluntary agencies provide care of better quality than that provided by government with respect to primary curative outpatient services in Dar-es-Salaam. All non-government primary services were included, and government primary facilities were randomly sampled within the three districts of the city. Details of consultations were recorded and assessed by a panel who classed consultations as adequate, inadequate but serious consequences unlikely, and consultations where deficiencies in the care could have serious consequences. Interpersonal conduct was assessed and exit interviews were conducted. The study found that government registers of non-government 'voluntary' providers actually contained a high proportion of for-profit private providers. Comparisons between facilities showed that care was better overall at voluntary providers, but that there was a high level of inadequate care at both government and non-government providers.

Rapid, low-cost, two-step method to screen for urinary schistosomiasis at the district level: the Kilosa experience

The operational and diagnostic performance of a two-step method for the cost-effective screening of urinary schistosomiasis was investigated in the Kilosa District of east-central Tanzania. In the first step a simple questionnaire was administered to 15,073 primary schoolchildren by their class teachers over a 4-week period. The answers to the questionnaires had a high negative predictive value for schistosomiasis, and this permitted the safe exclusion of schools where the risk of the disease was low. In the second step, the head-teachers of the 49 high-risk schools and of 26 low-risk schools were instructed on the use of reagent sticks to detect haematuria. Each head-teacher then performed this test on 80 children selected at random in their schools (5750 children were screened within 6 weeks). Crosschecks of the results in 18 schools confirmed the reliability of the head-teachers' testing and their findings were therefore used to prepare an epidemiological map of the district and to arrange for treatment of positive children. This two-step approach relied entirely on the existing school system and permitted screening of a rural district of area 15,000 km2 (population, 350,000) over a 4-month period at a cost of only US$3000.