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)

BCG scar survey among primary school children in Kenya (1986-1990).

Bacillus Calmette Guerin (BCG) vaccination is essential in the control of tuberculosis (TB) especially in countries like Kenya where TB is still a public health problem and BCG is given to all children at birth as a matter of policy. The present survey was launched in 1986 to assess both BCG vaccination coverage and to compare its findings with the 1979/81 BCG scar survey results. Using random cluster sampling procedures, all primary school children aged 6-13 years from schools in each of 12 districts were included in the survey. A total of 46357 school children were registered. Of these, 3642 (7.9%) were excluded from the survey for a variety of reasons. Of the remaining 42715 (92.1%) children, 26781 (62.7%) had BCG scars present. Overall there was a significant upward trend of 15% in BCG vaccination coverage in the country. However, in some districts the coverage was found to have fallen quite significantly.

PIP: In 1986-1990, researchers conducted a BCG scar survey in 360 randomly selected primary schools in 12 districts in Kenya to determine BCG vaccination coverage. They used primary schools because more than 70% of all school age children were enrolled in school. They compared this survey's findings with those of the 1979-1981 BCG scar house-to-house survey. The districts included Elgeyo Marakwet, Kakamega, Kilifi, Kisii, Kitui, Siagya, Kwale, Meru, Muranga, Nakuru, Nairobi, and South Nyanza. The ages of the 42,715 healthy children ranged from 6-13 years old. 26,781 (62.7%) children had a BCG scar, indicating that the National Tuberculosis Control Program had not yet reached its target of 70% BCG vaccination coverage. Nairobi had the highest BCG coverage, while Kisii district had the lowest BCG coverage (82.73% vs. 44.01%). BCG coverage decreased as age increased (p .001). For example, 6-year-old males and females had a BCG coverage rate of 64.43% and 62.39%, respectively, while the corresponding figures for 13-year-olds were 52.93% and 49.13%. BCG vaccination coverage increased significantly between the two surveys (an increase of 15%) (60.8% vs. 62.7%; p .01). South Nyanza district experienced the greatest improvement in BCG coverage between the 2 surveys, while Kilifi district experienced the greatest decline in coverage. The greatest upward trend was observed in the Western and Rift Valley provinces, while the greatest downward trend was observed in the Coast and Eastern provinces.

Tuberculin survey among primary school children in Kenya

In Kenya; the first national tuberculin testing was conducted in 1958/59 by WHO/UNICEF. For the 30 years or so that followed; the National Tuberculosis Control Programme has depended on this old data and the unreliable; incomplete and inaccurate hospital records. The present tuberculin survey was launched in 1986 in 12 randomly selected districts using WHO standard mantoux testing and reading procedures to assess the skin sensitivity after BCG vaccination; the prevalence of tuberculosis infection; the annual risk of tuberculous infection and to compare the findings with the 1958/59 results. Its field work was completed in early 1990. Using radom cluster sampling procedure; all the schoolchildren in standard 1-3 from the 360 randomly selected schools in the 12 districts were included in the survey. The results from the study indicate that a total of 46;357 children were registered. 42;715 of them were examined for the presence of BCG scar and 37.3 were found to be non vaccinated. 93 of the tuberculin tested children were read and 36.5 of those children reacted with indurations of less than 2mm to 2 TU PPD RT 23 with Tween 80 40.6 of the BCG vaccinated and 29.5 of the non-vaccinated group had similar reactions. The prevalence of tuberculosis was found to be 8.7 and the annual risk of infection 1.1. This is a decline of 1.1 and 1.4 respectively since the last tuberculin survey. Enhanced research on tuberculosis is recommended

Epidemiology of acute respiratory tract infections among young children in Kenya.

The epidemiology of acute respiratory tract infection (ARI) was investigated in a rural community 80 km north of Nairobi, Kenya. This research was conducted prospectively on 250 families with 470 children less than 5 years of age who were contacted every 8 days during the 3-year study. The yearly incidence of respiratory tract infections decreased from 5.2 to 3.4 during the study; less than 5% of these infections involved the lower respiratory tract. The incidence was inversely related to age, and the illnesses were generally mild and brief in length. Fifteen children died during the study period. The precise causes of death are unknown, but respiratory infections possibly played a role in most cases. This study emphasizes the importance of determining the risk factors responsible for unusually severe morbidity and high mortality in children with ARI in developing countries.

Mortality patterns in a rural Kenyan community.

Causes of death of 239 children below the age of 5 years in a rural community were determined using structured questionnaires. It was found that mortality was highest in infancy, accounting for 63% of all deaths with a trend of decreasing mortality with increasing age. The commonest cause of death was ARI (pneumonia and measles) accounting for 49% of the deaths, followed by diarrhoeal illnesses (8.8%). Only half of the deaths (51.5%) occurred at some health facility, though 77% of all children had been taken to a health facility for treatment during the fatal illness.

Verbal autopsy: a tool for determining cause of death in a community.

Verbal autopsy was used to determine causes of death in 239 children under the age of 5 years. The diagnosis derived from verbal autopsy was corroborated with hospital diagnosis in 39 cases. There was concurrence of diagnosis in 72% of the cases. Using the diagnosis of bronchopneumonia to validate the method, verbal autopsy was found to have a sensitivity of 71%, specificity of 92%, a positive predictive value of 85%. Reliability index of agreement was 0.654. Recall period up to 29 months after death was found to be reliable.

Oral rehydration therapy and social marketing in rural Kenya.

In just a few years, oral rehydration therapy (ORT) has become the standard treatment to reduce infant diarrhoeal disease mortality in the developing world. The paper describes an ORT intervention campaign in a rural area in Western Kenya (Kakamega District). After about a year of careful preparation, the campaign was launched in January 1986 and compared the use of a value-added product (flavoured sachets) sold through private outlets in addition to primary care distribution of an unflavoured sachet in an experimental cell (Bukura Division). In a control cell (Novakholo Division), only unflavoured sachets were distributed free of charge through primary health care facilities. Using local perceptions of diarrhoeal disease management, the campaign in the experimental cell was carefully designed and mass communication techniques employed and adapted accordingly. Outcome assessments of the campaign, which lasted until March 1987, included the overall ORT utilisation over time. Changes in perceptions towards diarrhoeal disease management, direct assessments of mixing a 'safe and effective' solution accurately and other relevant process parameters were evaluated. Comparing several recent ORT intervention projects, the paper concludes that a combination of a commercial approach and mass communication techniques can further ORS use. If a proper incentive system for shopkeepers is installed and message design and ORS product are fully tailored to the perception and preferences of the target population, the commercial availability of ORS will create an extra demand of the product. However, this will not replace distribution of ORS salts delivered free of charge through primary care sources.

A study of the use of maternity and child welfare clinics in case-finding for pulmonary tuberculosis in Kenya.

This investigation is the seventh in a series of case-finding studies in Kenya. It explores the potential value of questioning mothers attending maternity and child welfare (M & CW) clinics to identify tuberculosis suspects (individuals aged 6 years or more with a cough for 1 month or more or hemoptysis) living in their households. The study was carried out in all the eight M & CW clinics in two divisions (populations 86,000 and 112,000) of two different districts. The mothers were asked to give a standard letter, which explained the possible importance of a chronic cough, to each suspect they identified and invited the suspect to attend the district hospital chest clinic. Each suspect attending the clinic was entered in a special register and two sputum specimens were collected. For those who failed to attend, the specimens were collected at a home visit. Of the total of 342 suspects living in the two study areas who were registered at the M & CW clinics during 1 year, 261 were identified by the mothers but 19 denied having received the standard letter. The remaining 81 had not been identified by mothers but had attended the M & CW clinics on their own initiative. Of the 242 suspects who received the letter, 89 (39%) attended the hospital chest clinic, 74% within a week of the letter being issued from the M & CW clinic. The main reasons given for not attending the hospital chest clinic by the remaining suspects were financial or because their cough had improved or disappeared. Sputum was collected from 238 suspects and examined bacteriologically: in six (2.5%) it was positive for tubercle bacilli on smear and culture and in a further two (0.8%) the sputum was positive on culture only. Of those attending the hospital chest clinic 2.9% were smear- and culture-positive and 4.7% were culture positive. This method of case-finding has yielded disappointing results, for only 4% of the estimated annual incidence of smear-positive cases was detected.