Tuberculosis and the HIV epidemic: increasing annual risk of tuberculous infection in Kenya, 1986-1996.

OBJECTIVES: The purpose of this study was to assess the impact of the increased incidence of tuberculosis (TB) due to HIV infection on the risk of TB infection in schoolchildren. METHODS: Tuberculin surveys were carried out in randomly selected primary schools in 12 districts in Kenya during 1986 through 1990 and 1994 through 1996. Districts were grouped according to the year in which TB notification rates started to increase. HIV prevalence in TB patients and changes in TB infection prevalence were compared between districts. RESULTS: Tuberculous infection prevalence rates increased strongly in districts where TB notification rates had increased before 1994 (odds ratio = 3.1, 95% confidence interval = 2.3, 4.1) but did not increase in districts where notification rates had increased more recently or not at all. HIV prevalence rates in TB patients were 50% in districts with an early increase in notification rates and 28% in the other study districts. CONCLUSIONS: Countries with an increasing prevalence of HIV infection will need additional resources for TB control, not only for current patients but also for the patients in additional cases arising from the increased risk of TB infection.

National tuberculin survey of Kenya, 1986-1990.

SETTING: The first tuberculin survey conducted in Kenya by the World Health Organisation in 1958-1959 found an annual risk of tuberculosis infection (ARTI) of 2.5%. OBJECTIVE: To estimate the ARTI and its trend in recent years and to compare the estimated incidence rates with the notification rates. DESIGN: A tuberculin survey was held in 12 randomly selected districts in the period 1986-1990. Tuberculin testing with 2TU PPD RT 23 + Tween 80 was performed in 40,365 primary schoolchildren aged 6-13. RESULTS: Of 14,984 non BCG-vaccinated children, 1,380 (9.2%) had indurations of > or = 10 mm. Double testing with PPD RT 23 and PPD-scrofulaceum in 980 non BCG-vaccinated children revealed a high level of infections due to mycobacteria other than tuberculosis (MOTT). Therefore, the prevalence of tuberculous infection was based on the sum of 50% of the indurations of 17 mm and all indurations of 18 mm or more multiplied by two. The prevalence of tuberculous infection in schoolchildren aged on average 8.4 years, 'weighted' for the population size according to the provisional results of the 1989 census, was calculated at 5.5%. The corresponding ARTI is 0.6%. CONCLUSION: The ARTI has declined by an average 4.6% per year. The tuberculosis problem differs from one area to the next, with the highest prevalences of infection on the coast and in Eastern Kenya, and the lowest in Western Kenya. Although the average ratio of observed and estimated incidences indicate that 70% of incident cases are notified, considerable inter-district variations are observed.

Essential drugs supply and usage as a reflection of outpatient morbidity in Kirinyaga District, Kenya.

This study was carried out in all the twenty eight Government rural health facilities (RHF's) in Kirinyaga District of Kenya. It aimed at determining whether the quantities and types of drugs supplied to the RHF's matched the morbidity patterns, and also whether the disease patterns continued to be used as a basis for requesting stocks of essential drugs. It also investigated the constraints associated with the programme with an ultimate aim of improving service delivery. The information was obtained through records review of the Bin card books, Out-patients Department (OPD) register, morbidity monthly returns, staff and patient interviews. A highly significant (p < 0.01) variation in morbidity (workload) by season of the year and between the ecological divisions of the district was observed. Significant differences were also observed between the quantities of drugs supplied and the actual monthly requirements in all the RHF's, implying that the disease patterns were not necessarily being used for requesting stocks of essential drugs. A distribution of essential drugs based on two broad ecological divisions of the district was recommended. One of the major constraints found to be associated with the Essential Drugs Programme was the delay in procurement/distribution of essential drugs to the RHF's. This was mainly due to the tendering procedures of Kit 2 by the Ministry of Health (MOH) and also occasional lack of transport at the district level.

Effect of non-tuberculous Mycobacteria infection on tuberculin results among primary school children in Kenya.

Few tuberculosis studies carried out in Kenya since 1948 have reported on the variations of the occurrence and geographical distributions of non-tuberculous Mycobacteria infection. They have however not been able to clearly relate infection outcome to the use of tuberculin tests as epidemiologic and clinical tool. The present survey, conducted by Kenya Medical Research Institute in collaboration with the International Union Against Tuberculosis and Lung Diseases between 1986 and 1990 among school children aged 6-13 years in 18 randomly selected districts, investigated the following: the prevalence of sensitivity to tuberculin PPD RT 23 and PPD scrofulaceum RS 95 sensitin; geographic distribution of the reactions from the tests and; the influence of non-tuberculous Mycobacteria on the tuberculin results. The WHO cluster sampling procedures were used to select 30 schools in each of the 18 districts. Each child was tested with an intradermal dose of 2 TU of PPD RT 23 with Tween 80 (PPD RT 23) on the right hand and 2 TU of PPD Scrofulaceum RS 95 sensitin with tween 80 (PPD RS 95) on the left hand. The results were read after 72 hours of testing. A total of 1015 BCG scar negative children was included in the survey. Of these, 981 were tested and read. Over 47% of the children did not react to both antigens while 6.1% and 22.7% reacted to human type tuberculin and environmental sensitin respectively. There was cross reaction between the two tests in 23.8% of the children from low altitude area who had more and larger reaction to the tests than the middle and higher altitude regions of the country.(ABSTRACT TRUNCATED AT 250 WORDS)