Amos Kahwa

National Institute for Medical Research (NIMR), Dār es Salām, Dar es Salaam, Tanzania

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Publications (15)19.21 Total impact

  • Tropical Medicine & International Health 11/2013; · 2.94 Impact Factor
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    ABSTRACT: To estimate the accuracy of self-screening for contraindications to combined oral contraceptive pills (COCs) and to estimate the proportion of women with contraindications to hormonal methods among those using drug shops in Tanzania. Trained nurses interviewed 1651 women aged 18-39years who self-screened for contraindications to COCs with the help of a poster at drug shops in Tanzania. Nurse assessment of the women served as the gold standard for comparison with self-assessment. Blood pressure was also measured onsite. Nurses reported that 437 (26.5%) women were not eligible to use COCs, compared with 485 (29.4%) according to self-report. Overall, 133 (8.1%) women who said that they were eligible were deemed ineligible by nurses. The rate of ineligibility was artificially high owing to participant and nurse assessments that were incorrectly based on adverse effects of pill use and cultural reasons, and because of the sampling procedure, which intercepted women regardless of their reasons for visiting the drug shop. Adjusted rates of ineligibility were 8.6% and 12.7%, respectively, according to nurse and participant assessment. Both nurses and women underestimated the prevalence of hypertension in the present group. Self-screening among women in rural and peri-urban Tanzania with regard to contraindications to COC use was comparable to assessment by trained nurses.
    International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics 07/2013; · 1.41 Impact Factor
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    ABSTRACT: We developed and piloted a methodology to establish TB related work load at primary care level for clinical and laboratory staff. Workload is influenced by activities to be implemented, time to perform them, their frequency and patient load. Of particular importance is the patient pathway for diagnosis and treatment and the frequency of clinic visits. Using observation with checklists, clocking, interviews and review of registers, allows assessing the contribution of different factors on the workload.
    Human Resources for Health 05/2012; 10:11. · 1.83 Impact Factor
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    ABSTRACT: Cardiovascular disease (CVD) is the leading cause of adult mortality in low-income countries but data on the prevalence of cardiovascular risk factors such as hypertension are scarce, especially in sub-Saharan Africa (SSA). This study aims to assess the prevalence of hypertension and determinants of blood pressure in four SSA populations in rural Nigeria and Kenya, and urban Namibia and Tanzania. We performed four cross-sectional household surveys in Kwara State, Nigeria; Nandi district, Kenya; Dar es Salaam, Tanzania and Greater Windhoek, Namibia, between 2009-2011. Representative population-based samples were drawn in Nigeria and Namibia. The Kenya and Tanzania study populations consisted of specific target groups. Within a final sample size of 5,500 households, 9,857 non-pregnant adults were eligible for analysis on hypertension. Of those, 7,568 respondents ≥ 18 years were included. The primary outcome measure was the prevalence of hypertension in each of the populations under study. The age-standardized prevalence of hypertension was 19.3% (95%CI:17.3-21.3) in rural Nigeria, 21.4% (19.8-23.0) in rural Kenya, 23.7% (21.3-26.2) in urban Tanzania, and 38.0% (35.9-40.1) in urban Namibia. In individuals with hypertension, the proportion of grade 2 (≥ 160/100 mmHg) or grade 3 hypertension (≥ 180/110 mmHg) ranged from 29.2% (Namibia) to 43.3% (Nigeria). Control of hypertension ranged from 2.6% in Kenya to 17.8% in Namibia. Obesity prevalence (BMI ≥ 30) ranged from 6.1% (Nigeria) to 17.4% (Tanzania) and together with age and gender, BMI independently predicted blood pressure level in all study populations. Diabetes prevalence ranged from 2.1% (Namibia) to 3.7% (Tanzania). Hypertension was the most frequently observed risk factor for CVD in both urban and rural communities in SSA and will contribute to the growing burden of CVD in SSA. Low levels of control of hypertension are alarming. Strengthening of health care systems in SSA to contain the emerging epidemic of CVD is urgently needed.
    PLoS ONE 01/2012; 7(3):e32638. · 3.73 Impact Factor
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    ABSTRACT: Setting. Tanzania. Objective. To compare microscopy as conducted in direct observation of treatment, short course centers to pouched rats as detectors of Mycobacterium tuberculosis. Design. Ten pouched rats were trained to detect tuberculosis in sputum using operant conditioning techniques. The rats evaluated 910 samples previously evaluated by smear microscopy. All samples were also evaluated through culturing and multiplex polymerase chain reaction was performed on culture growths to classify the bacteria. Results. The patientwise sensitivity of microscopy was 58.0%, and the patient-wise specificity was 97.3%. Used as a group of 10 with a cutoff (defined as the number of rat indications to classify a sample as positive for Mycobacterium tuberculosis) of 1, the rats increased new case detection by 46.8% relative to microscopy alone. The average samplewise sensitivity of the individual rats was 68.4% (range 61.1-73.8%), and the mean specificity was 87.3% (range 84.7-90.3%). Conclusion. These results suggest that pouched rats are a valuable adjunct to, and may be a viable substitute for, sputum smear microscopy as a tuberculosis diagnostic in resource-poor countries.
    Tuberculosis research and treatment. 01/2012; 2012:716989.
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    ABSTRACT: This article describes Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling (APOPO) recent use of specially trained African giant pouched rats as detectors of pulmonary tuberculosis in people living in Tanzania. It summarizes the achievements and challenges encountered over the years and outlines future prospects. Since 2008, second-line screening by the rats has identified more than 2000 tuberculosis-positive patients who were missed by microscopy at Direct Observation of Treatment – Short Course centres in Tanzania. Moreover, data that are reviewed herein have been collected with respect to the rats’ sensitivity and specificity in detecting tuberculosis. Findings strongly suggest that scent-detecting rats offer a quick and practical tool for detecting pulmonary tuberculosis and within the year APOPO’s tuberculosis-detection project will be extended to Mozambique. As part of its local capacity building effort, APOPO hires and trains Tanzanians to play many important roles in its TB detection project and provides research and training opportunities for Tanzanian students.
    Tanzania journal of health research 01/2012; 14(2).
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    ABSTRACT: Resource-limited settings in sub-Saharan African countries. To utilise African giant pouched rats (Cricetomys gambianus) for the diagnosis of tuberculosis (TB) in human sputum. A specially designed cage with 10 sniffing holes and cassette-carrier was used. The sputum samples were put in the sample cassette, containing 10 samples in line, placed under matching sniffing holes. Rats were trained to sniff each consecutive sample, and indicate TB positives by fixing their nose for 5 seconds at the sniffing hole. This behaviour was maintained by food reinforcement upon correct indications. A total of 3416 samples were used. Of the 20 trained rats, 18 were able to discriminate positive from negative sputum samples, with average daily sensitivities ranging from 72% to 100%, and average daily false-positives ranging from 0.7% to 8.1%. The use of multiple rats significantly increased sensitivity and negative predictive value. Utilising trained sniffer rats for TB detection is a potentially faster screening method and is at least as sensitive as smear microscopy. This method could therefore be suitable for active case finding, especially where large numbers of samples are to be analysed in resource-limited settings, to complement existing diagnostic techniques.
    The international journal of tuberculosis and lung disease: the official journal of the International Union against Tuberculosis and Lung Disease 07/2009; 13(6):737-43. · 2.61 Impact Factor
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    ABSTRACT: Hemorrhage is the leading cause of obstetric mortality. Studies show that Active Management of Third Stage of Labor (AMTSL) reduces Post Partum Hemorrhage (PPH). This study describes the practice of AMTSL and barriers to its effective use in Tanzania. A nationally-representative sample of 251 facility-based vaginal deliveries was observed for the AMTSL practice. Standard Treatment Guidelines (STG), the Essential Drug List and medical and midwifery school curricula were reviewed. Drug availability and storage conditions were reviewed at the central pharmaceutical storage site and pharmacies in the selected facilities. Interviews were conducted with hospital directors, pharmacists and 106 health care providers in 29 hospitals visited. Data were collected between November 10 and December 15, 2005. Correct practice of AMTSL according to the ICM/FIGO definition was observed in 7% of 251 deliveries. When the definition of AMTSL was relaxed to allow administration of the uterotonic drug within three minutes of fetus delivery, the proportion of AMTSL use increased to 17%. The most significant factor contributing to the low rate of AMTSL use was provision of the uterotonic drug after delivery of the placenta. The study also observed potentially-harmful practices in approximately 1/3 of deliveries. Only 9% out of 106 health care providers made correct statements regarding the all three components of AMTSL. The national formulary recommends ergometrine (0.5 mg/IM) or oxytocin (5 IU/IM) on delivery of the anterior shoulder or immediately after the baby is delivered. Most of facilities had satisfactory stores of drugs and supplies. Uterotonic drugs were stored at room temperature in 28% of the facilities. The knowledge and practice of AMTSL is very low and STGs are not updated on correct AMTSL practice. The drugs for AMTSL are available and stored at the right conditions in nearly all facilities. All providers used ergometrine for AMTSL instead of oxytocin as recommended by ICM/FIGO. The study also observed harmful practices during delivery. These findings indicate that there is a need for updating the STGs, curricula and training of health providers on AMTSL and monitoring its practice.
    Health Research Policy and Systems 05/2009; 7:6. · 1.38 Impact Factor
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    A. Kahwa, G.S. Mfinanga, M.Thiede
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    ABSTRACT: Background: The impact of the HIV pandemic in Tanzania has been profound and has affected all sectors. The availability of free antiretroviral therapy (ART) showed to significantly prolong and improve quality of life of people infected with HIV. Objectives: Establish the socioeconomic status of those who benefit most from the provision of free ARV in terms of utilization in urban and rural settings. Methodology: cross-sectional study to HIV patients who access free antiretroviral therapy in the selected rural and urban district hospitals. The questions were synchronized with the Tanzania Demographic and Health Survey (TDHS) and an asset index was constructed based on household ownership of durable goods and housing characteristics using principal components analysis (PCA). Findings: Overall, the uptake of free antiretroviral treatment in public facilities in Tanzania is relatively higher within the less poor population groups. This pattern is more pronounced in urban areas than rural areas. The study, however, could not assess utilization with respect to health care needs. Conclusion: targeting of free ARV provision in Tanzania should be improved. It is hoped that the findings from the study will help policy makers to set clear policy guidelines, which prioritize vulnerable, poor and marginalized groups of the population. Key words: ARV, HIV, Socio-Economic Status, Quintiles
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    ABSTRACT: Patient's satisfaction with both private and public laboratory services is important for the improvement of the health care delivery in any country. A cross-sectional survey was conducted in 24 randomly selected health facilities with laboratories that are conducting HIV related testing, in Mainland Tanzania. The study assessed patient's satisfaction with the laboratory services where by a total of 295 patients were interviewed. Of data analyzed for a varying totals from 224 to 294 patients, the percentage of dissatisfaction with both public and private laboratory services, ranged from 4.3% to 34.8%, with most of variables being more than 15%. Patients who sought private laboratory services were less dissatisfied with the cleanness (3/72, 4.2%) and the privacy (10/72, 13.9%) than those sought public laboratory service for the same services of cleanness (41/222, 18.5%) and privacy (61/222, 27.5%), and proportional differences were statistically significant (X2 = 8.7, p = 0.003 and X2 = 5.5, p = 0.01, respectively). Patients with higher education were more likely to be dissatisfied with privacy (OR = 1.8, 95% CI: 1.1-3.1) and waiting time (OR = 2.5, 95% CI: 1.5 - 4.2) in both private and public facilities. Patients with secondary education were more likely to be dissatisfied with the waiting time (OR = 5.2; 95%CI: 2.2-12.2) and result notification (OR = 5.1 95%CI (2.2-12.2) than those with lower education. About 15.0% to 34.8% of patients were not satisfied with waiting time, privacy, results notification cleanness and timely instructions. Patients visited private facilities were less dissatisfied with cleanness and privacy of laboratory services than those visited public facilities. Patients with higher education were more likely to be dissatisfied with privacy and waiting time in both private and public facilities.
    BMC Health Services Research 02/2008; 8:167. · 1.77 Impact Factor
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    ABSTRACT: A comprehensive care and treatment program requires a well functioning laboratory services. We assessed satisfaction of medical personnel to the laboratory services to guide process of quality improvement of the services. A cross-sectional survey in 24 randomly selected health facilities in Mainland Tanzania was conducted to assess the satisfaction of the medical personnel with the laboratory services. Of 235 medical personnel interviewed, 196 were valid for analysis and about one quarter were dissatisfied with the laboratory services. Personnel dissatisfied with the services were 38.3% in timely test result, 24.5% in correct and accurate results and 22.4% in clear complete results. The personnel in public laboratories were more dissatisfied with timely test results (OR = 3.6, 95% CI 1.8, 7.3), correct results (OR = 4.1, 95% CI 1.6, 10.8) and clear complete results (OR = 5.0 95% CI 1.6, 15.2). Personnel dissatisfied with the services in 15 laboratories sending specimens to referral laboratories, varied from 13% in availability of equipment to 57% in timely results feedback from the referral laboratories. Personnel dissatisfied with the services in 14 referral laboratories, varied from 28.6% in properly identified specimen to 42.9% in clear, accurate test request and communication. About one quarter of medical personnel in sending or receiving laboratories were dissatisfied with the services. Comparing the personnel in public and private, the personnel in public laboratories were 4 times more dissatisfied with the timely test and correct results; and 5 times more dissatisfied with clear and complete test results.
    BMC Health Services Research 02/2008; 8:171. · 1.77 Impact Factor
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    ABSTRACT: To assess the magnitude and factors responsible for delay in TB management. A cross sectional hospital based survey in Dar es Salaam region, May 2006. We interviewed 639 TB patients. A total of 78.4% of patients had good knowledge on TB transmission. Only 35.9% had good knowledge on the symptoms. Patient delay was observed in 35.1% of the patients, with significantly (X2 = 5.49, d.f. = 1, P = 0.019) high proportion in females (41.0%) than in males (31.5%). Diagnosis delay was observed in 52.9% of the patients, with significantly (X2 = 10.1, d.f. = 1, P = 0.001) high proportion in females (62.1%) than in males (47.0%). Treatment delay was observed in 34.4% of patients with no significant differences among males and females. Several risk factors were significantly associated with patient's delays in females but not in males. The factors included not recognizing the following as TB symptoms: night sweat (OR = 1.92, 95% CI 1.20, 3.05), chest pain (OR = 1.62, 95% CI 1.1, 2.37), weight loss (OR = 1.55, 95% CI 1.03, 2.32), and coughing blood (OR = 1.47, 95% CI 1.01, 2.16). Other factors included: living more than 5 Km from a health facility (OR = 2.24, 95% CI 1.41, 3.55), no primary education (OR = 1.74, 95% CI 1.01, 3.05) and no employment (OR = 1.77, 95% CI 1.20, 2.60). In multiple logistic regression, five factors were more significant in females (OR = 2.22, 95% CI 1.14, 4.31) than in males (OR = 0.70, 95% CI 0.44, 1.11). These factors included not knowing that night sweat and chest pain are TB symptoms, a belief that TB is always associated with HIV infection, no employment and living far from a health facility. There were significant delays in the management of TB patients which were contributed by both patients and health facilities. However, delays in most of patients were due to delay of diagnosis and treatment in health facilities. The delays at all levels were more common in females than males. This indicates the need for education targeting health seeking behaviour and improvement in health system.
    BMC Health Services Research 01/2008; 8:158. · 1.77 Impact Factor
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    ABSTRACT: Previous studies have shown that the cost of HIV/AIDS on the health care sector will exert impacts on other sectors, thus a big challenge to the country's health system. To determine source of fund and the cost associated with laboratory test of HIV related infections in Tanzania. The cost analysis was limited to seven out of the 26 regions of the United Republic of Tanzania. In each region, the costing process was undertaken at different levels of health facilities in order to cater for any variations in the types and cost of the laboratory services delivered at each level. The total number of 53926 people took HIV related tests which is equivalent of about 6114 people in every laboratory per a year. The financial cost of HIV related test services of the capita assets is estimated at USD 58,000 while annual economic cost on HIV related test services is estimated at USD 9.4 M. It was also found that USD 16,900 was spent on training overall total of 88 staff. The total cost of laboratory supplies and consumables used for testing was USD 550,300 of which USD 504,000 were used on HIV related tests. Recurrent/variable cost claimed 95% of the total cost of delivering HIV test related services of which about 85% was spent on laboratory supplies and consumables while capital cost was only 5%. The findings show that in order to scale up HIV test services putting enough money for lab supplies and consumables is important. The main source of funding for buildings and staff time is the Government because HIV test services take place within the existing structure of health facility in Tanzania while lab equipment, lab supplies and lab consumables are funded mainly by non government agencies. INTRODUCTION people living with HIV and AIDS (WHO, 2004). It is HIV/AIDS is one of the major public health problems to be infected with HIV. According to Laurent and with adverse effects on the socio-economic development Diakhote (2002) HIV/AIDS is the leading cause of adult of many developing countries. Current statistics indicate deaths in sub-Saharan Africa. In the year 2000 alone, an that over 42 million people worldwide are infected with estimated 2.4 million out of the global total of 3 million HIV among whom over 27 million are in sub-Saharan adult and child deaths from HIV/AIDS occurred in the Africa (WHO, 2004). The epidemic has claimed almost African region. Tanzania is one of the highly affected 19 million lives over the past 2 decades including 4 million countries in Sub-Saharan Africa with about 2.5 million children. Further, the epidemic is one of the contributing people infected with HIV and an estimated prevalence of factors to orphaned children. 9.6% (NACP, 2005). Studies indicate that HIV/AIDS has left over The impact of the HIV pandemic in Tanzania has 15 million children orphaned in its wake (WHO, 2004). been p rofound and has affected all sectors. Today, Sub-Saharan Africa is the world's most severely affected HIV/AIDS is recognized not only as a major public health region, with only 10% of the world's population concern but also as social, economic and development harbouring about two thirds of the global total number of problem in Tanzania as in most in Sub-Saharan African estimated that one in 12 adults in this region is reported
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    01/2008;
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    ABSTRACT: Tanzania is scaling up prevention, treatment, care and support of individuals affected with HIV. There is therefore a need for high quality and reliable HIV infection testing and AIDS staging. The objective of this study was to assess laboratories capacities of services in terms of HIV testing and quality control. A baseline survey was conducted from December 2004 to February 2005 in 12 laboratories which were conveniently selected to represent all the zones of Tanzania. The questionnaires comprised of questions on laboratory particulars, internal and external quality control for HIV testing and quality control of reagents. Source and level of customer satisfaction of HIV test kits supply was established. Of 12 laboratories, nine used rapid tests for screening and two used rapid tests for diagnosis. In the 12 laboratories, four used double ELISA and five used single ELISA and three did not use ELISA. Confirmatory tests observed were Western Blot in three laboratories, DNA PCR in two laboratories, CD4 counting in seven laboratories, and viral load in two laboratories. Although all laboratories conducted quality control (QC) of the HIV kits, only two laboratories had Standard Operating Procedures (SOPs). Internal and external quality control (EQC) was done at varied proportions with the highest frequency of 55.6% (5/9) for internal quality control (IQC) for rapid tests and EQC for ELISA, and the lowest frequency of 14.3% (1/ 7) for IQC for CD4 counting. None of the nine laboratories which conducted QC for reagents used for rapid tests and none of the five which performed IQC and EQC had SOPs. HIV kits were mainly procured by the Medical Store Department and most of laboratories were not satisfied with the delay in procurement procedures. Most of the laboratories used rapid tests only, while some used both rapid tests and ELISA method for HIV testing. In conclusion, the survey revealed inadequacy in Good Laboratory Practice and poor laboratory quality control process for HIV testing reagents, internal and external quality control.
    Tanzania health research bulletin 02/2007; 9(1):44-7.