49 results on '"Tembo G"'
Search Results
2. Economic modelling of a lignocellulosic biomass biorefining industry.
- Author
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Epplin, F. M., primary, Mapemba, L. D., additional, and Tembo, G., additional
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- 2005
- Full Text
- View/download PDF
3. Apparent vertical transmission of human immunodeficiency virus type 1 by breast-feeding in Zambia
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Hira, S.K., Mangrola, U.G., Mwale, C., Chintu, C., Tembo, G., Brady, W.E., and Perine, P.L.
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AIDS (Disease) in children -- Risk factors ,Breast feeding -- Health aspects ,HIV infection -- Demographic aspects ,Health - Abstract
Human immunodeficiency virus type 1 (HIV), the agent which causes AIDS, can be transmitted from mother to child during pregnancy, labor, or the postpartum period. HIV has been found in breast milk, but the significance of this to AIDS transmission has been unclear. To determine whether breast-feeding is a significant source of HIV transmission, the risk factors for maternal HIV infection and for transmission to infants were studied in 1,954 African women who recently gave birth. Of these, 1,720 women tested negative for HIV, but only 634 women returned for follow-up testing one year later. Nineteen women in this group subsequently tested positive for HIV, and 3 of the 19 children became HIV-positive as well. The only known exposure to HIV for these children was through breast-feeding. The risk factors for HIV infection for the women were, from least to greatest risk, husbands with HIV infection; blood transfusions; genital ulcers; and practicing 'dry sex', in which vaginal secretions are removed with a cloth, a practice which may abrade the vagina and facilitate HIV transmission. The study suggests that women who are at high risk of acquiring HIV should not breast-feed their children due to a small risk of transmission. However, in Africa, neither formula feeding nor safe water supplies are generally available or affordable. The advantage of breast-feeding in preventing infant death from diarrheal disease usually is greater than the risk of HIV transmission. (Consumer Summary produced by Reliance Medical Information, Inc.)
- Published
- 1990
4. Perinatal Transmission Of HIV-I In Zambia
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Hira, S. K., Kamanga, J., Bhat, G. J., Mwale, C., Tembo, G., Luo, N., and Perine, P. L.
- Published
- 1989
5. Conservation farming in Zambia
- Author
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Haggblade, S., Tembo, G., and Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase
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Labor costs ,Conservation agriculture ,Soil conservation ,Small-scale farming ,Conservation farming ,Ecosystem Farm/Enterprise Scale Field Scale ,Soil degradation - Abstract
This IFPRI report discusses experiences with conservation farming in Zambia since 1996. The programs discussed focus on dry season land preparation with minimal tillage, retention of crop residue from the prior harvest, planting in fixed planting stations, and nitrogen fixing crop rotations.
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- 2003
6. Early evidence on conservation farming in Zambia
- Author
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Haggblade, S., Tembo, G., Haggblade, S., and Tembo, G.
- Abstract
Conservation farming practices such as minimium tillage, crop residue retention, precision input application, and nitrogen-fixing crop rotations offer some sustainable farming methods for Zambian smallholder farmers. These methods improve soil structure and water retention while increasing crop yields. In 2002/3 about 75,000 Zambian smallholder farmers implemented some of these methods and of these about 15,000 are spontaneous adopters. The remaining 60,000 practice the conservation methods as a condition for receiving their inputs. Adoption rates are highest in areas with sporadic rainfall, strong extension and input supply systems. Conservation farming appears promising although the benefits and problems will only become apparent over time.
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- 2003
7. Conservation farming in Zambia
- Author
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Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase, Haggblade, S., Tembo, G., Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase, Haggblade, S., and Tembo, G.
- Abstract
This IFPRI report discusses experiences with conservation farming in Zambia since 1996. The programs discussed focus on dry season land preparation with minimal tillage, retention of crop residue from the prior harvest, planting in fixed planting stations, and nitrogen fixing crop rotations.
- Published
- 2003
8. Early evidence on conservation farming in Zambia
- Author
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Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase, Haggblade, S., Tembo, G., Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase, Haggblade, S., and Tembo, G.
- Abstract
Conservation farming practices such as minimium tillage, crop residue retention, precision input application, and nitrogen-fixing crop rotations offer some sustainable farming methods for Zambian smallholder farmers. These methods improve soil structure and water retention while increasing crop yields. In 2002/3 about 75,000 Zambian smallholder farmers implemented some of these methods and of these about 15,000 are spontaneous adopters. The remaining 60,000 practice the conservation methods as a condition for receiving their inputs. Adoption rates are highest in areas with sporadic rainfall, strong extension and input supply systems. Conservation farming appears promising although the benefits and problems will only become apparent over time.
- Published
- 2003
9. The impact of human immunodeficiency virus on presentation and diagnosis of tuberculosis in a cohort study in Zambia
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Alison Elliott, Halwiindi B, Rj, Hayes, Luo N, Tembo G, Machiels L, Bem C, Steenbergen G, Jo, Pobee, and Pp, Nunn
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Adult ,Male ,Adolescent ,Tuberculin Test ,Age Factors ,Sputum ,Zambia ,HIV Infections ,Mycobacterium tuberculosis ,Tuberculosis, Pleural ,HIV Antibodies ,Cohort Studies ,Sex Factors ,HIV Seroprevalence ,HIV-1 ,Humans ,Tuberculosis ,Female ,Prospective Studies ,Pericardium ,Tuberculosis, Cardiovascular ,Tuberculosis, Pulmonary - Abstract
Two hundred and forty-nine patients with tuberculosis were recruited to a cohort study to investigate the interaction between tuberculosis and HIV in Lusaka, Zambia; findings at presentation are presented here. One hundred and eighty-two (73%; 95% confidence interval 67-79%) of the cases were HIV-1 antibody positive. The diagnosis of tuberculosis was confirmed by microscopy for acid-alcohol fast bacilli, culture of Mycobacterium tuberculosis, or histology in 74% of all cases. HIV negative and positive cases differed in site of disease: among HIV negative patients 72% had pulmonary disease alone, 16% extrapulmonary disease alone and 12% had both, whereas among HIV positive patients 40% had pulmonary disease alone, 34% extrapulmonary disease alone and 26% both (P0.001). HIV negative and positive cases were compared with regard to outcome of diagnostic procedures: 55% of HIV negative cases could be diagnosed at enrollment by sputum smear, but only 35% of HIV positive cases (P0.01). Among pulmonary cases confirmed by sputum culture, 76% of HIV negative patients had a positive sputum smear, compared with 57% of HIV positive patients (P = 0.09). Pleural and pericardial disease were difficult to confirm, but culture of pleural fluid was positive in 12/46 HIV positive patients, compared with 0/11 HIV negative patients. Lymph node disease was readily confirmed by biopsy. The tuberculin test was positive in only 30/110 (27%) of HIV positive cases, but in 21/38 (55%) of HIV negative cases (P0.01). Mycobacterium tuberculosis was cultured in 57% of HIV negative cases and 54% of HIV positive cases; no atypical mycobacteria were isolated. Initial resistance to isoniazid was present in isolates from 5% of cases with a positive culture.
- Published
- 1993
10. Human Immunodeficiency Virus Infection Dynamics in East Africa Deduced from Surveillance Data
- Author
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Stonebumer, R. L., primary, Low-Beer, D., additional, Tembo, G. S., additional, Mertens, T. E., additional, and Asiimwe-Okiror, G., additional
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- 1996
- Full Text
- View/download PDF
11. National STD trends in Zambia 1987-89.
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Tembo, G, primary
- Published
- 1993
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- View/download PDF
12. Impact of HIV on tuberculosis in Zambia: a cross sectional study.
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Elliott, A M, primary, Luo, N, additional, Tembo, G, additional, Halwiindi, B, additional, Steenbergen, G, additional, Machiels, L, additional, Pobee, J, additional, Nunn, P, additional, Hayes, R J, additional, and McAdam, K P, additional
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- 1990
- Full Text
- View/download PDF
13. Syphilis intervention in pregnancy: Zambian demonstration project.
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Hira, S K, primary, Bhat, G J, additional, Chikamata, D M, additional, Nkowane, B, additional, Tembo, G, additional, Perine, P L, additional, and Meheus, A, additional
- Published
- 1990
- Full Text
- View/download PDF
14. Perinatal transmission of HIV-I in Zambia
- Author
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Hira, S.K., Kamanga, J., Bhat, G.J., Mwale, C., Tembo, G., Luo, N., and Perine, P.L.
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AIDS (Disease) ,AIDS (Disease) in pregnancy -- Statistics ,AIDS (Disease) in children ,AIDS virus carriers -- Statistics ,AIDS (Disease) in pregnancy -- Case studies ,Medical screening -- Evaluation ,Zambia -- Health aspects - Published
- 1989
15. Individual counseling of patients with sexually transmitted diseases. A way to improve partner notification in a Zambian setting?
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Faxelid E, Tembo G, Ndulo J, and Krantz I
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- 1996
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16. Participatory evaluation of counselling, medical and social services of The AIDS Support...
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KALEEBA, N., KALIBALA, S., KASEJE, M., SSEBBANJA, P., ANDERSON, S., VAN PRAAG, E., TEMBO, G., and KATABIRA, E.
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AIDS patients ,HUMAN services - Abstract
Summarizes the results of the participatory evaluation of The AIDS Support Organization (TASO) services from August 1993 over a one year period. Overview of AIDS care services; Findings indicating that TASO services were being received by those in need; Instrumentality in bringing about family and community support; Development of a consistent rational monitoring system.
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- 1997
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17. Syphilis intervention in pregnancy: Zambian demonstration project.
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Hira, S K, Bhat, G J, Chikamata, D M, Nkowane, B, Tembo, G, Perine, P L, and Meheus, A
- Abstract
Despite availability of simpler serologic tests for syphilis and near cure with penicillin, unacceptably high prevalence of infectious maternal syphilis exist in many developing countries, including Zambia. It is the foremost risk factor for mid-trimester abortions, stillbirths, prematurity and morbidity and mortality among infants born with congenital syphilis in Zambia. An intervention project was conducted in Lusaka aimed at demonstrating the effectiveness of new health education methods and prenatal screening for syphilis in reducing the adverse outcomes during pregnancy. During pre-intervention phase, approximately 150 consecutive pregnant women from each of the three study and the three control centres were recruited when they presented in labour at the University Teaching Hospital. The intervention phase lasted for one year at the three study centres during which new methods of health education were introduced to improve early attendances during pregnancy. Also, on-site syphilis screening was performed twice during pregnancy and seroreactive women, and in many cases their sexual partners, were treated by the existing prenatal clinic staff. During the post-intervention phase the steps of pre-intervention phase were repeated to evaluate the impact of intervention. Overall, 8.0% of women were confirmed seroreactive for syphilis; there was no difference between the study and the control centres (p greater than 0.05). Fifty seven percent (132/230) of syphilitic pregnancies ended with an adverse outcome, that is, abortion (RR 5.0), stillbirth (RR 3.6), prematurity (RR 2.6) and low birth weight (RR 7.8). The overall risk of adverse outcomes due to syphilis was 8.29 (95% confidence interval 6.53, 10.53). The new methods of health education were effective and the percentage of women who had their first prenatal visit under 16 weeks of gestation improved from 9.4 to 42.5. Although screening and treatment during intervention was suboptimal, the adverse outcomes attributable to syphilis were reduced to 28.3%; this is almost a two-third reduction when compared with 72.4% of adverse outcomes at control centres (p < less than 0.001). The intervention is culturally and politically acceptable in Zambia. The cost of each prenatal screening is US$0.60 and of averting each adverse outcome US$12. In countries with high rates of syphilis, there is an urgent need for STD control and Maternal and Child Health (MCH) programmes to pool their resources together to revitalise the prenatal care. [ABSTRACT FROM PUBLISHER]
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- 1990
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- View/download PDF
18. Perinatal transmission of HIV-1 in Zamibia.
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Hirs, S.K., Kamanga, J., Bhat, G.J., Mwale, C., Tembo, G., Lou, N., and Perine, P.L.
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HIV infection transmission ,HIV-positive women ,PREGNANCY ,INFANT diseases ,DISEASE risk factors - Abstract
Determines the occurrence of vertical transmission of HIV infected (I) pregnant women in Zambia. Prognosis of HIV-I on babies of pregnant women; Prevalence of vertical transmission of HIV-I mothers to infants in the country; Ways for the reduction of HIV perinatal transmission and pediatric AIDS.
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- 1989
19. The impact of HIV on infectiousness of pulmonary tuberculosis: a community study in Zambia
- Author
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Alison Elliott, Rj, Hayes, Halwiindi B, Luo N, Tembo G, Jo, Pobee, Pp, Nunn, and Kp, Mcadam
- Subjects
Adult ,Male ,Adolescent ,Tuberculin Test ,Statistics as Topic ,Infant, Newborn ,Infant ,Zambia ,HIV Infections ,Cohort Studies ,Cross-Sectional Studies ,Risk Factors ,Child, Preschool ,HIV Seropositivity ,HIV-1 ,Humans ,Female ,Contact Tracing ,Child ,Tuberculosis, Pulmonary - Abstract
To examine the impact of HIV on infectiousness of pulmonary tuberculosis (TB).A cross-sectional tuberculin survey carried out among household contacts of HIV-1-positive and negative patients with bacteriologically confirmed pulmonary TB. Contacts were also examined for active TB.Index cases were recruited from patients attending the University Teaching Hospital in Lusaka, Zambia and household contacts were examined during visits to their homes within Lusaka.A total of 207 contacts of 43 HIV-positive patients, and 141 contacts of 28 HIV-negative patients with pulmonary TB were examined.Proportion of contacts of HIV-positive and negative index cases with a positive tuberculin response (diameter of indurationor = 5 mm to a dose of 2 tuberculin units).Fifty-two per cent of contacts of HIV-positive pulmonary TB patients had a positive tuberculin response compared with 71% of contacts of HIV-negative patients (odds ratio, 0.43; 95% CI, 0.26-0.72; P0.001). This difference persisted after allowing for between-household variations in the tuberculin response. Tuberculin response in the contact was related to age of contact, intimacy with the index case and crowding in the household. However, the effect of HIV status of the index case was not confounded by these variables. Tuberculin response in the contact was also related to the number of bacilli seen in the sputum smear of the index case which partially explained the effect of HIV status of the index case. Active TB was diagnosed in 4% of contacts of HIV-positive and 3% of contacts of HIV-negative cases, respectively (P = 0.8).HIV-positive patients with pulmonary TB may be less infectious than their HIV-negative counterparts and this may partly be explained by lower bacillary load in the sputum.Between April and December 1989, the chest clinic of the University Teaching Hospital in Lusaka, Zambia, confirmed pulmonary tuberculosis (TB) in 141 adults, 95 (67%) of whom were HIV-1 seropositive. Health workers made home visits to 71 of the index cases (43 HIV-1 positive and 28 HIV-1 negative) to learn whether the 348 household members would also develop TB, thus allowing researchers to determine the effect of HIV on infectiousness of TB. Contacts of HIV-1 positive patients developed TB at a lower rate than did those of HIV-1 negative patients (52% vs. 71%; odds ratio [OR] = 0.43; p .001). This difference continued even after controlling for between-household variations, indicating that confounding variables did not account for the difference. Age of contact, intimacy with the index case, and crowding in the household were associated with the tuberculin response in the contact, but they did not confound the effect of HIV status. Tuberculin response in the contact was associated with the number of bacilli in the sputum smear (crude OR = 3.13; p = .013, and adjusted OR =1.84; p = .28), suggesting that the number of bacilli somewhat explained the difference in infectiousness between HIV-1 positive and HIV-1 negative patients. 12 contacts (8 of HIV-positive cases and 4 of HIV-negative cases) developed active TB after the TB diagnosis in the index case. These findings clearly demonstrated that infection with Mycobacterium tuberculosis was less likely in household members of HIV-1 positive cases than in those of HIV-1 negative cases. The lower bacillary load in the sputum in HIV- 1 cases may have accounted somewhat for the lower infectiousness of pulmonary TB.
20. Integrated crop and livestock risk modeling
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Tembo, G., Simeon Kaitibie, and Epplin, F.
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fungi ,food and beverages ,Production Economics, Risk and Uncertainty - Abstract
This study was conducted to determine risk efficient production strategies for crop and livestock producers who have the opportunity to produce wheat as a dual-purpose forage and grain crop. Empirical data obtained from field trials were incorporated into an integrated crop and livestock production and marketing risk programming model.
21. Preventive chemotherapy for HIV-associated tuberculosis in Uganda: An operational assessment at a voluntary counselling and testing centre
- Author
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Aisu, T., Mario RAVIGLIONE, Praag, E., Eriki, P., Narain, J. P., Barugahare, L., Tembo, G., Mcfarland, D., and Adatu Engwau, F.
- Subjects
Counseling ,Male ,AIDS-Related Opportunistic Infections ,Tuberculin Test ,Cost-Benefit Analysis ,Immunology ,Mycobacterium tuberculosis ,Infectious Diseases ,Isoniazid ,Humans ,Tuberculosis ,Immunology and Allergy ,Female ,Uganda - Abstract
To assess the operational aspects of isoniazid preventive chemotherapy (IPT) for tuberculosis in persons dually infected with HIV and Mycobacterium tuberculosis identified at an independent HIV voluntary counselling and testing centre in Kampala, Uganda.HIV-infected persons were counselled, had active tuberculosis excluded by medical examination, and were offered purified protein derivative (PPD) skin testing. PPD-positive persons were offered isoniazid 300 mg daily for 6 months. Drugs were supplied, and toxicity and compliance were assessed monthly. Utilization of service, cost, and sustainability were also assessed.Between 14 June 1991 and 30 September 1992, 9862 persons tested HIV-positive. Of 5594 HIV-infected clients who returned to collect test results, only 1524 (27%) were enrolled. Of those, 1344 were tuberculin-tested (88%); 180 were not tested because of active tuberculosis, serious illnesses, refusal, and other reasons. Of the 1344, 250 (19%) did not return for test reading and 515 were negative (47% of tests read). Of 579 tuberculin-positive persons, 59 (10%) were excluded from preventive chemotherapy because of tuberculosis and other respiratory illnesses. Of 520 persons given isoniazid, 62% collected at least 80% of their drug supplies. No major toxicity was observed. One case of tuberculosis occurred in the first month of treatment. Cost of HIV counselling and testing was US $18.54 per person and cost of follow-up counselling and social support was US $7.89.Important factors were identified which caused attrition, such as limited motivation by counsellors to discuss tuberculosis issues during HIV pre- and post-test counselling, insufficient availability of medical screening, shifting of sites to collect pills, and frequent tuberculin-negative tests. Active tuberculosis among 6% of persons screened suggests that voluntary counselling and testing sites may be important for tuberculosis case finding and underscores the need to exclude tuberculosis carefully before starting IPT. In developing countries, further studies assessing the feasibility of IPT within tuberculosis and HIV/AIDS programme conditions are needed. Cost-effectiveness of IPT, compared with passive case finding, and its sustainability should be assessed before national policies are established.Those infected with human immunodeficiency virus (HIV) have a 5-10% risk per year of developing active tuberculosis, and this disease may accelerate the clinical course of HIV infection. Thus, a study was conducted in Uganda to assess the cost-effectiveness and acceptability of isoniazid preventive chemotherapy (IPT) for patients dually diagnosed with HIV and Mycobacterium tuberculosis. Of the 1344 HIV-infected patients at an independent HIV testing and counseling center in Kampala who were initially screened for participation in this study, 6% had signs of active tuberculosis. Selected for participation in the study were 520 subjects with no signs of active tuberculosis. Of these, 322 (62%) were considered compliant with the treatment regimen on the basis of their appearance for all scheduled appointments for pill distribution. One case of active tuberculosis occurred during the first month of IPT and most likely represented a case that went undetected in the screening process. No treatment-associated toxicity was reported. The cost of the HIV testing and counseling was US$18.54 per patient; that of follow-up counseling and support was $7.89. When administrative costs for the study were included in the calculation, the cost of IPT increased to $60.19 per person. Although reactivation of tuberculosis may have been prevented in up to 62% of subjects who received IPT, numerous factors mitigate against the routine implementation of such a treatment program, most notably its high cost and a shortage of voluntary HIV centers in developing countries. Needed are studies that evaluate the long-term community health, social, and economic benefits of such a program as well as further investigations of the impact of tuberculosis on the pace of progression from HIV to acquired immunodeficiency syndrome (AIDS).
22. Preventive chemotherapy for HIV-associated tuberculosis in Uganda: an operational assessment at a voluntary counseling and testing centre
- Author
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Aisu, T., Raviglione, M.C., Vanpraag, E., Eriki, P., Narain, J.P., Barugahare, L., Tembo, G., Mcfarland, D., and Engwau, F.A.
- Subjects
Tuberculosis -- Prevention ,Isoniazid -- Health aspects - Abstract
According to the authors' abstract of an article published in AIDS, "OBJECTIVE: To assess the operational aspects of isoniazid preventive chemotherapy (IPT) for tuberculosis in persons dually infected with HIV [...]
- Published
- 1995
23. Change in sexual behaviour and decline in HIV infection among young pregnant women in urban Uganda
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Asiimweokiror, G., Opio, A.A., Musinguzi, J., Madraa, E., Tembo, G., and Carael, M.
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HIV infection in pregnancy -- Demographic aspects ,Young adults -- Sexual behavior ,Uganda -- Health aspects - Abstract
HIV/AIDS (Sexual Behavior) Asiimweokiror, G.; Opio, A.A.; Musinguzi, J.; Madraa, E.; Tembo, G.; Carael, M. "Change in Sexual Behaviour and Decline in HIV Infection among Young Pregnant Women in Urban [...]
- Published
- 1998
24. National STD trends in Zambia 1987-89.
- Author
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Tembo, G
- Published
- 1993
- Full Text
- View/download PDF
25. Natural carriage of Streptococcus pneumoniae is associated with increased experimental pneumococcal carriage but reduced conjugate vaccine efficacy in a human challenge model.
- Author
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Galafa B, Chikaonda T, Kudowa E, Sichone S, Sibale L, Thole F, Mkandawire C, Dula D, Nsomba E, Tembo G, Chaponda M, Chirwa AE, Nkhoma V, Ngoliwa C, Kamng'ona R, Toto N, Makhaza L, Muyaya A, Howard A, Nyazika TK, Ndaferankhande J, Chimgoneko L, Banda NPK, Chiwala G, Rylance J, Ferreira D, Jambo KC, Morton B, Henrion MYR, and Gordon SB
- Abstract
Background: In Malawi, the national pneumococcal conjugate vaccine (PCV13) demonstrated less herd immunity than the USA, likely due to higher natural pneumococcal carriage rates. We assessed PCV13 efficacy against experimental pneumococcal carriage in healthy Malawian adults. We explored how natural carriage (pneumococcal carriage of any other serotype apart from 6B) influenced experimental carriage rates and vaccine efficacy., Methods: Healthy adults aged 18-40 were randomly assigned PCV13 (n=98) or saline (n=106), followed by intranasal SPN 6B inoculation at 20,000 (n=40), 80,000 (n=74), or 160,000 (n=90) CFU/100µl, 28 days post-vaccination. We evaluated natural and experimental pneumococcal carriage before and after vaccination on days 2, 7, and 14 post-inoculation using culture and multiplex qPCR targeting lytA/cpsA genes and compared carriage rates by vaccination status., Results: Of 204 participants, 19.6% (40) exhibited experimental carriage, detected by culture and 25.5% (52) by qPCR. Vaccinated individuals had lower experimental carriage rates (10.2%, n=10/98) compared to the placebo group (28.3%, n=30/106). This difference in vaccine efficacy was more pronounced in participants without natural carriage (PCV13=8% n=6/75 vs. placebo=25.9%, n=21/81) compared to those with natural carriage (PCV13=14.8%, n=4/27 vs. placebo=26.5%, n=9/34). Using a log-binomial model, vaccine effectiveness (VE) was 62%, whether assessed by culture or qPCR. Natural carriers had a lower VE of 52% compared to participants with no natural carriage (VE=69%)., Conclusion: We have shown that PCV13 VE estimate (62%) is robust whether carriage is assessed by culture or qPCR. PCV13 had lower VE in natural carriers compared to those without natural carriage at the inoculation visit., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
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- 2024
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- View/download PDF
26. Differences in condom access and use and associated factors between persons with and without disabilities receiving social cash transfers in Luapula province, Zambia-A cross-sectional study.
- Author
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Chipanta D, Estill J, Stöckl H, Toska E, Chanda P, Mwanza J, Kaila K, Matome C, Tembo G, and Keiser O
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- Humans, Female, Male, Zambia, Adult, Adolescent, Cross-Sectional Studies, Young Adult, Middle Aged, HIV Infections epidemiology, HIV Infections prevention & control, HIV Infections economics, Health Services Accessibility statistics & numerical data, Health Services Accessibility economics, Condoms statistics & numerical data, Disabled Persons statistics & numerical data
- Abstract
Persons with disabilities are disadvantaged in accessing sexual and reproductive health services, including condoms. In this study, we investigated whether condom access and use and their associated factors differed between persons with and without disabilities. We used data from adults in households receiving the Government of Zambia social cash transfers (SCT) in four districts of Luapula province. Condom access and use was the outcome. Disability, defined by the Washington Group Short Set Questions on Disability, was the main predictor. We performed logistic regression analyses to determine the associations between condom access and use and disability. In multivariable analyses, we controlled for covariates including age, sex, marital status, poverty status, HIV testing, and receiving the SCT. The sample comprised 1,143 people aged 16-49, with a median age of 21 years (interquartile range 18-28); 57.4% (n = 656) were female, 86.5% (n = 989) accessed and used condoms, and 17.9% (n = 205) were disabled, rating themselves with a 3 or a 4 on a scale of 1 = "not limited" to 4 = "cannot at all" in performing any of the six daily functions (seeing, hearing, walking, cognition, self-care, or communicating). Nearly sixty percent(58.5% (n = 120)) of persons with disabilities were female, 79.5% (n = 163) reported being very poor, 87.8% (n = 180) reported receiving SCT, and 86.3% (n = 177) reported accessing and using condoms. Condom access and use did not differ between persons with and without disabilities (adjusted odds ratio: 1.09; 95% confidence interval [CI]: 0.60-1.98]). We found no differences between persons with and without disabilities in condom access and use. We established that individual-level factors such as age, sex, marital status, and knowledge of being HIV positive might play a more important role in condom access and use than disability. Condom promotion interventions should account for these factors., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Chipanta et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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27. Effect of 13-valent pneumococcal conjugate vaccine on experimental carriage of Streptococcus pneumoniae serotype 6B in Blantyre, Malawi: a randomised controlled trial and controlled human infection study.
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Dula D, Morton B, Chikaonda T, Chirwa AE, Nsomba E, Nkhoma V, Ngoliwa C, Sichone S, Galafa B, Tembo G, Chaponda M, Toto N, Kamng'ona R, Makhaza L, Muyaya A, Thole F, Kudowa E, Howard A, Kenny-Nyazika T, Ndaferankhande J, Mkandawire C, Chiwala G, Chimgoneko L, Banda NPK, Rylance J, Ferreira D, Jambo K, Henrion MYR, and Gordon SB
- Subjects
- Adult, Child, Humans, Malawi epidemiology, Vaccines, Conjugate, Serogroup, Streptococcus pneumoniae, Pneumococcal Vaccines therapeutic use
- Abstract
Background: The effect of childhood pneumococcal conjugate vaccine implementation in Malawi is threatened by absence of herd effect. There is persistent vaccine-type pneumococcal carriage in both vaccinated children and the wider community. We aimed to use a human infection study to measure 13-valent pneumococcal conjugate vaccine (PCV13) efficacy against pneumococcal carriage., Methods: We did a double-blind, parallel-arm, randomised controlled trial investigating the efficacy of PCV13 or placebo against experimental pneumococcal carriage of Streptococcus pneumoniae serotype 6B (strain BHN418) among healthy adults (aged 18-40 years) from Blantyre, Malawi. We randomly assigned participants (1:1) to receive PCV13 or placebo. PCV13 and placebo doses were prepared by an unmasked pharmacist to maintain research team and participant masking with identification only by a randomisation identification number and barcode. 4 weeks after receiving either PCV13 or placebo, participants were challenged with 20 000 colony forming units (CFUs) per naris, 80 000 CFUs per naris, or 160 000 CFUs per naris by intranasal inoculation. The primary endpoint was experimental pneumococcal carriage, established by culture of nasal wash at 2, 7, and 14 days. Vaccine efficacy was estimated per protocol by means of a log-binomial model adjusting for inoculation dose. The trial is registered with the Pan African Clinical Trials Registry, PACTR202008503507113, and is now closed., Findings: Recruitment commenced on April 27, 2021 and the final visit was completed on Sept 12, 2022. 204 participants completed the study protocol (98 PCV13, 106 placebo). There were lower carriage rates in the vaccine group at all three inoculation doses (0 of 21 vs two [11%] of 19 at 20 000 CFUs per naris; six [18%] of 33 vs 12 [29%] of 41 at 80 000 CFUs per naris, and four [9%] of 44 vs 16 [35%] of 46 at 160 000 CFUs per naris). The overall carriage rate was lower in the vaccine group compared with the placebo group (ten [10%] of 98 vs 30 [28%] of 106; Fisher's p value=0·0013) and the vaccine efficacy against carriage was estimated at 62·4% (95% CI 27·7-80·4). There were no severe adverse events related to vaccination or inoculation of pneumococci., Interpretation: This is, to our knowledge, the first human challenge study to test the efficacy of a pneumococcal vaccine against pneumococcal carriage in Africa, which can now be used to establish vaccine-induced correlates of protection and compare alternative strategies to prevent pneumococcal carriage. This powerful tool could lead to new means to enhance reduction in pneumococcal carriage after vaccination., Funding: Wellcome Trust., Competing Interests: Declaration of interests DF declares grant funding from Pfizer to her institution for separate projects and consulting fees from Pfizer, MSD, and Sanofi. All other authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)
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- 2023
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28. Women with disabilities in hearing: the last mile in the elimination of mother-to-child transmission of HIV - a cross-sectional study from Zambia.
- Author
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Chipanta D, Stöckl H, Toska E, Amo-Agyei S, Chanda P, Mwanza J, Kaila K, Matome C, Tembo G, Thiabaud A, Keiser O, and Estill J
- Subjects
- Cross-Sectional Studies, Female, Hearing, Humans, Infectious Disease Transmission, Vertical prevention & control, Pregnancy, Zambia epidemiology, Disabled Persons, HIV Infections diagnosis, HIV Infections epidemiology, Pregnancy Complications, Infectious
- Abstract
This article explored the differences in HIV testing in the elimination of mother-to-child transmission of HIV (EMTCT) between women with and without disabilities aged 16-55 years, reported being pregnant and receiving the social cash transfers (SCT) social safety nets in Luapula province, Zambia. We tested for associations between HIV testing in EMTCT and disability using logistic regression analyses. We calculated a functional score for each woman to determine if they had mild, moderate or severe difficulties and controlled for age, intimate partner sexual violence, and the SCT receipt. Of 1692 women, 29.8% (504) reported a disability, 724 (42.8%) mild, 203 (12.0%) moderate, and 83 (4.9%) severe functional difficulties (adjusted odds ratio [aOR] 1.33; 95% confidence interval [CI] 1.04-1.70). Women with moderate (aOR 2.04; 95% CI 1.44-2.88) or mild difficulties (aOR 1.66; 95% CI 1.32-2.08) or with a disability in cognition (aOR 1.67 95% CI 1.22-2.29) reported testing more for HIV than women without disabilities; Women with a disability in hearing (aOR 0.36 CI 0.16-0.80) reported testing less for HIV. Disability is common among women receiving the SCT in the study area accessing HIV testing in the EMTCT setting. HIV testing in EMTCT is challenging for women with disabilities in hearing.
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- 2022
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29. Facing the quality of life: physical illness, anxiety, and depression symptoms among people living with HIV in rural Zambia - a cross-sectional study.
- Author
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Chipanta D, Stöckl H, Toska E, Chanda P, Mwanza J, Kaila K, Matome C, Tembo G, Estill J, and Keiser O
- Subjects
- Adolescent, Adult, Anxiety epidemiology, Cross-Sectional Studies, Depression epidemiology, Female, Humans, Middle Aged, Young Adult, Zambia epidemiology, HIV Infections epidemiology, Quality of Life
- Abstract
Widespread access to ART has not improved the quality of life (QoL) for people living with HIV (PLHIV). We used the United Nations Disability project (UNPRPD) evaluation data to examine how physical illness, anxiety, and depression shape the QoL of PLHIV in households receiving the social cash transfers safety nets in Luapula, Zambia. We explored associations between each outcome - physical illness, anxiety, depression symptoms - and age, gender, poverty, hunger and disability, using univariable and multivariable regressions. We adjusted p -values for multiple hypothesis testing with sharpened Qs. The sample comprised 1925 respondents 16-55 years old, median age 31 (IQR 22-42 years), majority women ( n = 1514, 78.6%). Two-thirds (1239, 64.4%) reported having a physical illness, a third (671, 34.9%) anxiety, and nine per cent (366) depression symptoms. More HIV positive people had a disability (34.6%, 53 versus 28.3%, 502; Q = 0.033), were physically ill (72.5%, 111 versus 63.7%, 1128; Q = 0.011), and two-fold (aOR 1.97 95% CI 1.31-2.94) more likely to report depression symptoms than HIV negative peers. Food insecurity and disability among PLHIV may worsen their physical illnesses, anxiety, depression symptoms, and other QoL domains. More research on the quality of life of PLHIV in poverty is required.
- Published
- 2022
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30. AstraZeneca COVID-19 vaccine induces robust broadly cross-reactive antibody responses in Malawian adults previously infected with SARS-CoV-2.
- Author
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Chibwana MG, Moyo-Gwete T, Kwatra G, Mandolo J, Hermanaus T, Motlou T, Mzindle N, Ayres F, Chaponda M, Tembo G, Mwenechanya P, Mitole N, Jassi C, Kamng'ona R, Afran L, Mzinza D, Mwandumba HC, Gordon SB, Jere K, Madhi S, Moore PL, Heyderman RS, and Jambo KC
- Subjects
- Antibody Formation, COVID-19 Vaccines, Humans, Immunization, Passive, Prospective Studies, SARS-CoV-2, COVID-19 Serotherapy, COVID-19 prevention & control, COVID-19 therapy, Viral Vaccines pharmacology
- Abstract
Background: Binding and neutralising anti-Spike antibodies play a key role in immune defence against SARS-CoV-2 infection. Since it is known that antibodies wane with time and new immune-evasive variants are emerging, we aimed to assess the dynamics of anti-Spike antibodies in an African adult population with prior SARS-CoV-2 infection and to determine the effect of subsequent COVID-19 vaccination., Methods: Using a prospective cohort design, we recruited adults with prior laboratory-confirmed mild/moderate COVID-19 in Blantyre, Malawi, and followed them up for 270 days (n = 52). A subset of whom subsequently received a single dose of the AstraZeneca COVID-19 vaccine (ChAdOx nCov-19) (n = 12). We measured the serum concentrations of anti-Spike and receptor-binding domain (RBD) IgG antibodies using a Luminex-based assay. Anti-RBD antibody cross-reactivity across SARS-CoV-2 variants of concern (VOC) was measured using a haemagglutination test. A pseudovirus neutralisation assay was used to measure neutralisation titres across VOCs. Ordinary or repeated measures one-way ANOVA was used to compare log10 transformed data, with p value adjusted for multiple comparison using Šídák's or Holm-Šídák's test., Results: We show that neutralising antibodies wane within 6 months post mild/moderate SARS-CoV-2 infection (30-60 days vs. 210-270 days; Log ID
50 6.8 vs. 5.3, p = 0.0093). High levels of binding anti-Spike or anti-RBD antibodies in convalescent serum were associated with potent neutralisation activity against the homologous infecting strain (p < 0.0001). A single dose of the AstraZeneca COVID-19 vaccine following mild/moderate SARS-CoV-2 infection induced a 2 to 3-fold increase in anti-Spike and -RBD IgG levels 30 days post-vaccination (both, p < 0.0001). The anti-RBD IgG antibodies from these vaccinated individuals were broadly cross-reactive against multiple VOCs and had neutralisation potency against original D614G, beta, and delta variants., Conclusions: These findings show that the AstraZeneca COVID-19 vaccine is an effective booster for waning cross-variant antibody immunity after initial priming with SARS-CoV-2 infection. The potency of hybrid immunity and its potential to maximise the benefits of COVID-19 vaccines needs to be taken into consideration when formulating vaccination policies in sub-Saharan Africa, where there is still limited access to vaccine doses., (© 2022. The Author(s).)- Published
- 2022
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31. Associations of Sustainable Development Goals Accelerators With Adolescents' Well-Being According to Head-of-Household's Disability Status-A Cross-Sectional Study From Zambia.
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Chipanta D, Estill J, Stöckl H, Hertzog L, Toska E, Chanda P, Mwanza J, Kaila K, Matome C, Tembo G, Keiser O, and Cluver L
- Subjects
- Adolescent, Adult, Cross-Sectional Studies, Female, Humans, Poverty, Young Adult, Zambia, Adolescent Health, Sustainable Development
- Abstract
Objectives: We examined associations between accelerators (interventions impacting ≥2 SDG targets) and SDG-aligned well-being indicators among adolescents 16-24 years old in Zambia. Methods: We surveyed adults from 1,800 randomly sampled households receiving social cash transfers. We examined associations between accelerators (social cash transfers, life-long learning, mobile phone access) and seven well-being indicators among adolescents using multivariate logistic regressions. Results: The sample comprised 1,725 adolescents, 881 (51.1%) girls. Mobile phone access was associated with no poverty (adjusted Odds Ratio [aOR] 2.08, p < 0.001), informal cash transfers (aOR 1.82, p = 0.004), and seeking mental health support (aOR 1.61, p = 0.020). Social cash transfers were associated with no disability-related health restrictions (aOR 2.56, p = 0.004) and lesser odds of seeking mental health support (aOR 0.53, p = 0.029). Life-long learning was associated with informal cash transfers (aOR 3.49, p < 0.001) and lower school enrollment (aOR 0.70, p = 0.004). Adolescents with disabled head-of-household reported worse poverty, good health but less suicidal ideation. Conclusions: Social cash transfers, life-long learning, and mobile phone access were positively associated with well-being indicators. Adolescents living with disabled head-of-household benefited less. Governments should implement policies to correct disability-related inequalities., Competing Interests: CM and GT were employed by Palm Associates Limited. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Chipanta, Estill, Stöckl, Hertzog, Toska, Chanda, Mwanza, Kaila, Matome, Tembo, Keiser and Cluver.)
- Published
- 2022
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32. Can unconditional cash transfers raise long-term living standards? Evidence from Zambia.
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Handa S, Natali L, Seidenfeld D, Tembo G, and Davis B
- Abstract
In Africa, state-sponsored cash transfer programs now reach nearly 50 million people. Do these programs raise long-term living standards? We examine this question using experimental data from two unconditional cash transfer programs implemented by the Zambian Government. We find far-reaching effects of the programs both on food security and consumption as well as on a range of productive outcomes. After three years, household spending is on average 67 percent larger than the value of the transfer received, implying a sizeable multiplier effect, which works through increased non-farm activity and agricultural production.
- Published
- 2018
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33. Does money buy happiness? Evidence from an unconditional cash transfer in Zambia.
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Natali L, Handa S, Peterman A, Seidenfeld D, and Tembo G
- Abstract
The relationship between happiness and income has been at the center of a vibrant debate, with both intrinsic and instrumental importance, as emotional states are an important determinant of health and social behavior. We investigate whether a government-run unconditional cash transfer paid directly to women in poor households had an impact on self-reported happiness. The evaluation was designed as a cluster-randomized controlled trial in rural Zambia across 90 communities. The program led to a 7.5 to 10 percentage point impact on women's happiness after 36- and 48-months, respectively (or 0.19-0.25 standard deviations over the control group mean). In addition, women have higher overall satisfaction regarding their young children's well-being, including indicators of satisfaction with their children's health and positive outlook on their children's future. Complementary analysis suggests that self-assessed relative poverty (as measured by comparison to other households in the community) is a more important mediator of program effects on happiness than absolute poverty (as measured by household consumption expenditures). Although typically not the focus of such evaluations, impacts on psychosocial indicators, including happiness, should not be discounted as important outcomes, as they capture different, non-material, holistic aspects of an individual's overall level of well-being.
- Published
- 2018
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34. The Social and Productive Impacts of Zambia's Child Grant.
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Handa S, Seidenfeld D, Davis B, and Tembo G
- Abstract
Accumulated evidence from dozens of cash transfer programs across the world suggest that there are few interventions that can match the range of impacts and cost-effectiveness of a small, predictable monetary transfer to poor families in developing countries. However, individual published impact assessments typically focus on only one program and one outcome. This article presents two-year impacts of the Zambian Government's Child Grant, an unconditional cash transfer to families with children under age five, across a wide range of domains including consumption, productive activity and women and children's outcomes, making this one of the first studies to assess both protective and productive impacts of a national unconditional cash transfer program. We show strong impacts on consumption, food security, savings and productive activity. However, impacts in areas such as child nutritional status and schooling depend on initial conditions of the household, suggesting that cash alone is not enough to solve all constraints faced by these poor, rural households. Nevertheless, the apparent transformative effects of this program suggest that unconditional transfers in very poor settings can contribute to both protection and development outcomes.
- Published
- 2016
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35. Income Transfers and Maternal Health: Evidence from a National Randomized Social Cash Transfer Program in Zambia.
- Author
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Handa S, Peterman A, Seidenfeld D, and Tembo G
- Subjects
- Adult, Child, Preschool, Developing Countries, Female, Humans, Infant, Infant, Newborn, Maternal Health Services statistics & numerical data, Poverty, Preventive Health Services economics, Preventive Health Services statistics & numerical data, Regression Analysis, Zambia, Financing, Government economics, Health Services Accessibility economics, Income, Maternal Health, Maternal Health Services economics
- Abstract
There is promising recent evidence that poverty-targeted social cash transfers have potential to improve maternal health outcomes; however, questions remain surrounding design features responsible for impacts. In addition, virtually no evidence exists from the African region. This study explores the impact of Zambia's Child Grant Program on a range of maternal health utilization outcomes using a randomized design and difference-in-differences multivariate regression from data collected over 24 months from 2010 to 2012. Results indicate that while there are no measurable program impacts among the main sample, there are heterogeneous impacts on skilled attendance at birth among a sample of women residing in households having better access to maternal health services. The latter result is particularly interesting because of the overall low level of health care availability in program areas suggesting that dedicated program design or matching supply-side interventions may be necessary to leverage unconditional cash transfers in similar settings to impact maternal health., (Copyright © 2015 John Wiley & Sons, Ltd.)
- Published
- 2016
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36. The impact of Zambia's unconditional child grant on schooling and work: results from a large-scale social experiment.
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Handa S, Natali L, Seidenfeld D, and Tembo G
- Abstract
This paper reports the impact on child schooling and work of the Government of Zambia's Child Grant Program (CGP), an unconditional cash transfer program targeted to households with children under age 3 years in three districts of the country. Although the CGP's focus is on very young children, we look to see if the program has impacts on older children who are not the explicit target group. We use data from a large-scale social experiment involving 2,519 households, half of whom were randomized out to a delayed-entry control group, that was implemented to assess the impact of the program. We find that the CGP has no discernable impact on school enrollment of children age 7-14. However when we break the sample by older (11-14) and younger (7-10) children - based on the grade structure of the Zambian schooling system - we find a significant impact among children age 11-14 which coincided with the exact age range where sharp drop-out begins to occur in Zambia with point estimates in the range of 7-8 percentage points. Finally, we provide evidence on the potential pathways through which the unconditional cash transfer impacts on enrollment. Households in the CGP spend more on education, and in particular on uniforms and shoes, two items cited as key barriers to school enrollment in study areas.
- Published
- 2016
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37. The effect of food insecurity on mental health: panel evidence from rural Zambia.
- Author
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Cole SM and Tembo G
- Subjects
- Adult, Female, Humans, Linear Models, Male, Middle Aged, Retrospective Studies, Seasons, Surveys and Questionnaires, Zambia, Food Supply, Mental Health, Rural Population
- Abstract
A growing number of studies show support for a positive association between food insecurity and poor mental health in developing countries. Few of these studies, however, explore the relationship statistically employing longitudinal data. This study combines ethnography with randomly sampled household-level panel data (two waves) collected in 2009 to examine the association between food insecurity and mental health in rural Zambia. Mental health was measured using the Self-Reporting Questionnaire and food insecurity was assessed utilizing a modified 7-item scale based on local coping strategies used during food shortages. A multilevel linear regression model was employed with repeated measures nested within individuals (N = 280 observations) living in 81 households nested within 16 villages. Regression results confirm the postulated positive association between poor mental health and food insecurity. Food insecurity during the dry season, the time of year in rural Zambia when many households are typically food secure, had a subsequent greater effect on mental health than food insecurity during the rainy season. The difference in the effect was statistically significant at the five-percent level. In a country where mental health care resources are severely lacking, policy and applied efforts aimed at improving access to key agricultural resources, thereby increasing agricultural output, could potentially produce beneficial mental health outcomes., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
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38. Change in sexual behaviour and decline in HIV infection among young pregnant women in urban Uganda.
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Asiimwe-Okiror G, Opio AA, Musinguzi J, Madraa E, Tembo G, and Caraël M
- Subjects
- Adolescent, Adult, Age Factors, Condoms statistics & numerical data, Female, HIV Infections epidemiology, Humans, Male, Mass Screening, Pregnancy, Pregnancy Complications, Infectious epidemiology, Prevalence, Sexual Partners, Sexually Transmitted Diseases epidemiology, Uganda epidemiology, Urban Population, HIV Infections prevention & control, Pregnancy Complications, Infectious prevention & control, Sexual Behavior
- Abstract
Objective: To describe sexual behaviour that may partly explain a decline in HIV seroprevalence in pregnant women in urban settings in Uganda, East Africa., Settings: Two major urban districts in Uganda., Methods: Repeated population-based behavioural surveys in 1989 and 1995, and repeated HIV serological surveys in consecutive pregnant women attending antenatal clinics from 1989 to 1995., Results: During the study period, a 2-year delay in the onset of sexual intercourse among youths aged 15-24 years and a 9% decrease in casual sex in the past year in male youths aged 15-24 years were reported. Men and women reported a 40% and 30% increase in experience of condom use, respectively. In the same study area, over the same period, there was an overall 40% decline in the rates of HIV seroprevalence among pregnant women attending antenatal clinics. It can be hypothesized that the observed declining trends in HIV correspond to a change in sexual behaviour and condom use, especially among youths., Conclusions: This is the first report of a change over a period of 6 years in male and female sexual behaviour, assessed at the population level, that may partly explain the observed decline in HIV seroprevalence in young pregnant women in urban Uganda. This result should encourage AIDS control programmes to pursue their prevention activities.
- Published
- 1997
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39. Human immunodeficiency virus infection dynamics in east Africa deduced from surveillance data.
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Stoneburner RL, Low-Beer D, Tembo GS, Mertens TE, and Asiimwe-Okiror G
- Subjects
- Acquired Immunodeficiency Syndrome epidemiology, Adolescent, Adult, Age Distribution, Child, Disease Outbreaks statistics & numerical data, Female, Humans, Incidence, Male, Middle Aged, Models, Statistical, Morbidity trends, Prevalence, Sex Distribution, Uganda epidemiology, HIV Infections epidemiology, HIV-1, Population Surveillance
- Abstract
Knowledge of human immunodeficiency virus type 1 (HIV) incidence patterns in East African HIV epidemics like that in Uganda is fundamental for guiding interventions and forecasting the future course of the pandemic, yet they are difficult to determine from surveillance data. The authors deduce hypotheses of HIV incidence dynamics from birth cohort analyses of Ugandan acquired immunodeficiency syndrome (AIDS) incidence from 1987 to 1992 and from the age and sex distribution of sexually transmitted disease: an age dependency for HIV risk; a period effect of varying HIV incidence growth; and a replenishment of HIV-susceptible populations through demographic renewal. The hypotheses are tested by incorporating them into a model that generates patterns of HIV incidence, prevalence, and AIDS cases that are consistent with empiric data. When applied to Uganda, the modeled HIV incidence is characterized by a short temporal concentration of high incidence, followed by a decline, stabilization, and concentration in younger ages. The ensuing HIV dynamics result in a rapid build-up and subsequent stabilization of prevalence and mortality in years 10 and 13, respectively, after epidemic onset. When this model is used to forecast scenarios from 1980 to 2000, HIV prevalence declines in some populations, which is different from earlier scenarios. The techniques presented provide an empiric basis to better direct interventions, forecast epidemic impacts, and evaluate determinants of changing incidence and prevalence patterns.
- Published
- 1996
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40. Preventive chemotherapy for HIV-associated tuberculosis in Uganda: an operational assessment at a voluntary counselling and testing centre.
- Author
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Aisu T, Raviglione MC, van Praag E, Eriki P, Narain JP, Barugahare L, Tembo G, McFarland D, and Engwau FA
- Subjects
- AIDS-Related Opportunistic Infections economics, Cost-Benefit Analysis, Female, Humans, Male, Mycobacterium tuberculosis, Tuberculin Test, Tuberculosis economics, Uganda, AIDS-Related Opportunistic Infections prevention & control, Counseling economics, Isoniazid therapeutic use, Tuberculosis prevention & control
- Abstract
Objective: To assess the operational aspects of isoniazid preventive chemotherapy (IPT) for tuberculosis in persons dually infected with HIV and Mycobacterium tuberculosis identified at an independent HIV voluntary counselling and testing centre in Kampala, Uganda., Design: HIV-infected persons were counselled, had active tuberculosis excluded by medical examination, and were offered purified protein derivative (PPD) skin testing. PPD-positive persons were offered isoniazid 300 mg daily for 6 months. Drugs were supplied, and toxicity and compliance were assessed monthly. Utilization of service, cost, and sustainability were also assessed., Results: Between 14 June 1991 and 30 September 1992, 9862 persons tested HIV-positive. Of 5594 HIV-infected clients who returned to collect test results, only 1524 (27%) were enrolled. Of those, 1344 were tuberculin-tested (88%); 180 were not tested because of active tuberculosis, serious illnesses, refusal, and other reasons. Of the 1344, 250 (19%) did not return for test reading and 515 were negative (47% of tests read). Of 579 tuberculin-positive persons, 59 (10%) were excluded from preventive chemotherapy because of tuberculosis and other respiratory illnesses. Of 520 persons given isoniazid, 62% collected at least 80% of their drug supplies. No major toxicity was observed. One case of tuberculosis occurred in the first month of treatment. Cost of HIV counselling and testing was US $18.54 per person and cost of follow-up counselling and social support was US $7.89., Conclusions: Important factors were identified which caused attrition, such as limited motivation by counsellors to discuss tuberculosis issues during HIV pre- and post-test counselling, insufficient availability of medical screening, shifting of sites to collect pills, and frequent tuberculin-negative tests. Active tuberculosis among 6% of persons screened suggests that voluntary counselling and testing sites may be important for tuberculosis case finding and underscores the need to exclude tuberculosis carefully before starting IPT. In developing countries, further studies assessing the feasibility of IPT within tuberculosis and HIV/AIDS programme conditions are needed. Cost-effectiveness of IPT, compared with passive case finding, and its sustainability should be assessed before national policies are established.
- Published
- 1995
41. The impact of human immunodeficiency virus on response to treatment and recurrence rate in patients treated for tuberculosis: two-year follow-up of a cohort in Lusaka, Zambia.
- Author
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Elliott AM, Halwiindi B, Hayes RJ, Luo N, Mwinga AG, Tembo G, Machiels L, Steenbergen G, Pobee JO, and Nunn PP
- Subjects
- Adult, Drug Therapy, Combination, Female, Follow-Up Studies, Humans, Male, Prospective Studies, Recurrence, Survival Analysis, Treatment Outcome, Urban Health, Zambia, AIDS-Related Opportunistic Infections drug therapy, Antitubercular Agents therapeutic use, HIV-1, Tuberculosis drug therapy
- Abstract
To examine the effect of HIV on response to treatment and recurrence rate in patients with tuberculosis (TB), we have followed 239 previously untreated, adult, TB patients in a prospective cohort study in Lusaka, Zambia. One hundred and seventy-four (73%) were HIV-1 antibody positive. Patients with sputum smear positive, miliary, or meningeal TB were prescribed 2 months daily streptomycin, thiacetazone, isoniazid, rifampicin, pyrazinamide followed by 6 months thiacetazone and isoniazid; others, 2 months streptomycin, thiacetazone and isoniazid followed by 10 months thiacetazone and isoniazid. Thirty-five per cent of HIV-positive (HIV+ve) and 9% of HIV-negative (HIV-ve) patients were known to have died before the scheduled end of treatment. Surviving HIV+ve patients showed weight gain and improvement in symptoms and laboratory and radiological findings similar to HIV-ve patients. The risk of cutaneous drug reaction was 17% (95% CI: 12-25%) in HIV+ve, and 4% (1-13%) in HIV-ve patients. Severe rashes were attributed to thiacetazone. Recurrence of active TB was examined among 64 HIV+ve and 37 HIV-ve patients who successfully completed treatment, with mean follow-up after the end of treatment of 13.5 and 16.8 months, respectively. The rate of recurrence was 22/100 person years (pyr) for HIV+ve patients and 6/100 pyr for HIV-ve patients, giving a recurrence rate ratio of 4.0 (95% CI 1.2-13.8, P = 0.03).
- Published
- 1995
42. The impact of human immunodeficiency virus on mortality of patients treated for tuberculosis in a cohort study in Zambia.
- Author
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Elliott AM, Halwiindi B, Hayes RJ, Luo N, Mwinga AG, Tembo G, Machiels L, Steenbergen G, Pobee JO, and Nunn P
- Subjects
- AIDS-Related Opportunistic Infections complications, Adolescent, Adult, Aged, Antitubercular Agents therapeutic use, Cause of Death, Cohort Studies, Female, Humans, Male, Middle Aged, Patient Compliance, Prednisolone therapeutic use, Prospective Studies, Risk Factors, Survival Analysis, Tuberculosis complications, Tuberculosis drug therapy, Zambia epidemiology, AIDS-Related Opportunistic Infections mortality, HIV-1, Tuberculosis mortality
- Abstract
We have examined the impact of human immunodeficiency virus (HIV) on mortality of patients treated for tuberculosis in a prospective study in Lusaka, Zambia. Patients with sputum smear-positive, miliary, or meningeal tuberculosis were prescribed 2 months' daily streptomycin, thiacetazone, isoniazid, rifampicin, and pyrazinamide followed by 6 months thiacetazone and isoniazid; others, 2 months streptomycin, thiacetazone and isoniazid followed by 10 months thiacetazone and isoniazid. 239 patients (65 HIV-negative and 174 HIV-positive) were followed to 2 years from start of treatment. The crude mortality rate ratio for HIV-positive compared with HIV-negative patients over 2 years was 5.00 (95% confidence interval 2.30-10.86). Median survival for HIV-positive patients from the start of treatment was 22 months. At least 34% of HIV-positive patients for whom cause of death was known died from tuberculosis, three-quarters of these during the first month of treatment. Risk factors for death in HIV-positive patients included multi-site tuberculosis, history of prolonged diarrhoea or fever, oral thrush, splenomegaly, anergy to tuberculin, low weight, anaemia or lymphopenia, and poor compliance with regimens containing rifampicin and pyrazinamide. Tuberculosis, even treated, was a major cause of death in patients with HIV infection.
- Published
- 1995
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43. Tuberculin sensitivity and HIV-1 status of patients attending a sexually transmitted diseases clinic in Lusaka, Zambia: a cross-sectional study.
- Author
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Duncan LE, Elliott AM, Hayes RJ, Hira SK, Tembo G, Mumba GT, Ebrahim SH, Quigley M, Pobee JO, and McAdam KP
- Subjects
- AIDS-Related Opportunistic Infections epidemiology, AIDS-Related Opportunistic Infections immunology, Cross-Sectional Studies, Female, HIV Seropositivity epidemiology, HIV Seropositivity immunology, Humans, Male, Prevalence, Random Allocation, Risk Factors, Sexually Transmitted Diseases epidemiology, Tuberculin Test, Tuberculosis epidemiology, Tuberculosis immunology, Zambia epidemiology, AIDS-Related Opportunistic Infections complications, HIV Seropositivity complications, HIV-1, Tuberculosis complications
- Abstract
A cross-sectional study to estimate the prevalence of latent tuberculosis (TB) in a group of Zambians at high risk of human immunodeficiency virus type 1 (HIV-1) infection and to examine the effect of HIV-1 infection on the tuberculin response was conducted in the University Teaching Hospital in Lusaka, Zambia during July to September 1990. Patients were selected from those presenting to the out-patient clinic for first referral with either sexually transmitted or skin disease. 268 adults were included in the study; 158 (59%; 95% confidence interval [CI] = 53-65%) were HIV-1 antibody positive. Of 82 HIV-1 negative participants who returned for Mantoux skin test reading, 51 (62%; 95% CI = 57-67%) had a positive test reaction (diameter > or = 10 mm) after receiving 2 units of RT-23 tuberculin. Of 106 HIV-1 positive participants who returned, only 32 (30%; 95% CI = 26-34%) had a diameter > or = 10 mm. Nine (28%) of the HIV-1 positive and Mantoux positive participants had large reactions > or = 30 mm, compared to 4 (8%) of the HIV-1 negative, Mantoux positive participants (P = 0.03). Results in the HIV-1 negative group indicated a prevalence of latent TB of 62% in this population. HIV-1 infection was associated with a much higher frequency of negative response to tuberculin and with a few large skin test responses. Thus, in populations where HIV seropositivity is high, Mantoux skin tests cannot be used to assess those with latent TB who might benefit from chemoprophylaxis.
- Published
- 1995
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44. Bed occupancy due to HIV/AIDS in an urban hospital medical ward in Uganda.
- Author
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Tembo G, Friesan H, Asiimwe-Okiror G, Moser R, Naamara W, Bakyaita N, and Musinguzi J
- Subjects
- Adult, Female, HIV Infections mortality, HIV Seronegativity, HIV Seropositivity mortality, Hospital Units statistics & numerical data, Humans, Male, Morbidity, Uganda, World Health Organization, Acquired Immunodeficiency Syndrome epidemiology, Bed Occupancy statistics & numerical data, HIV Infections epidemiology, HIV Seropositivity epidemiology, Hospitals, Urban statistics & numerical data
- Abstract
Objective: To determine the proportion of patients with HIV-related illness admitted to a medical ward., Design: A prospective study., Setting: Rubaga Hospital, the third largest hospital in Kampala, the capital of Uganda., Participants: A total of 449 patients admitted to the medical ward between September and November 1992., Results: Of the 449 patients, 390 (86.8%) agreed to provide a blood sample for HIV serology. Of these, 55.6% (95% confidence interval, 50.7-60.5%) were positive for HIV. Eighty-six (22.2%) of all patients [71 (33%) of the seropositives and six (3.5%) of the seronegatives] met the World Health Organization case definition for AIDS in Africa. The HIV-seropositives had a mortality rate of 17.4%, significantly higher (P = 0.00057) than the 5.8% rate observed in the seronegative group. The overall mortality rate was 13.7% and was significantly associated with HIV infection (P = 0.0005)., Conclusion: HIV infection is a major contributor to morbidity and mortality in Uganda. Over 50% of the medical admissions were HIV-positive revealing the serious impact of HIV on the health-care system.
- Published
- 1994
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45. Limitations of the WHO/CDC clinical case definition for AIDS in Africa.
- Author
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Duncan LE, Elliott AM, Tembo G, Hira SK, and McAdam KP
- Subjects
- Africa, Humans, World Health Organization, Acquired Immunodeficiency Syndrome
- Published
- 1994
- Full Text
- View/download PDF
46. The impact of HIV on infectiousness of pulmonary tuberculosis: a community study in Zambia.
- Author
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Elliott AM, Hayes RJ, Halwiindi B, Luo N, Tembo G, Pobee JO, Nunn PP, and McAdam KP
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Cohort Studies, Contact Tracing, Cross-Sectional Studies, Female, HIV Infections epidemiology, HIV Seropositivity complications, HIV Seropositivity epidemiology, HIV-1 isolation & purification, Humans, Infant, Infant, Newborn, Male, Risk Factors, Statistics as Topic, Tuberculin Test, Tuberculosis, Pulmonary epidemiology, Zambia epidemiology, HIV Infections complications, HIV-1 pathogenicity, Tuberculosis, Pulmonary complications
- Abstract
Objective: To examine the impact of HIV on infectiousness of pulmonary tuberculosis (TB)., Design: A cross-sectional tuberculin survey carried out among household contacts of HIV-1-positive and negative patients with bacteriologically confirmed pulmonary TB. Contacts were also examined for active TB., Setting: Index cases were recruited from patients attending the University Teaching Hospital in Lusaka, Zambia and household contacts were examined during visits to their homes within Lusaka., Patients, Participants: A total of 207 contacts of 43 HIV-positive patients, and 141 contacts of 28 HIV-negative patients with pulmonary TB were examined., Main Outcome Measures: Proportion of contacts of HIV-positive and negative index cases with a positive tuberculin response (diameter of induration > or = 5 mm to a dose of 2 tuberculin units)., Results: Fifty-two per cent of contacts of HIV-positive pulmonary TB patients had a positive tuberculin response compared with 71% of contacts of HIV-negative patients (odds ratio, 0.43; 95% CI, 0.26-0.72; P < 0.001). This difference persisted after allowing for between-household variations in the tuberculin response. Tuberculin response in the contact was related to age of contact, intimacy with the index case and crowding in the household. However, the effect of HIV status of the index case was not confounded by these variables. Tuberculin response in the contact was also related to the number of bacilli seen in the sputum smear of the index case which partially explained the effect of HIV status of the index case. Active TB was diagnosed in 4% of contacts of HIV-positive and 3% of contacts of HIV-negative cases, respectively (P = 0.8)., Conclusions: HIV-positive patients with pulmonary TB may be less infectious than their HIV-negative counterparts and this may partly be explained by lower bacillary load in the sputum.
- Published
- 1993
- Full Text
- View/download PDF
47. The impact of human immunodeficiency virus on presentation and diagnosis of tuberculosis in a cohort study in Zambia.
- Author
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Elliott AM, Halwiindi B, Hayes RJ, Luo N, Tembo G, Machiels L, Bem C, Steenbergen G, Pobee JO, and Nunn PP
- Subjects
- Adolescent, Adult, Age Factors, Cohort Studies, Female, HIV Antibodies blood, HIV Infections epidemiology, HIV Seroprevalence, Humans, Male, Mycobacterium tuberculosis drug effects, Mycobacterium tuberculosis isolation & purification, Pericardium, Prospective Studies, Sex Factors, Sputum microbiology, Tuberculin Test, Tuberculosis diagnosis, Tuberculosis, Cardiovascular complications, Tuberculosis, Cardiovascular diagnosis, Tuberculosis, Pleural complications, Tuberculosis, Pleural diagnosis, Tuberculosis, Pulmonary complications, Tuberculosis, Pulmonary diagnosis, Zambia epidemiology, HIV Infections complications, HIV-1 immunology, Tuberculosis complications
- Abstract
Two hundred and forty-nine patients with tuberculosis were recruited to a cohort study to investigate the interaction between tuberculosis and HIV in Lusaka, Zambia; findings at presentation are presented here. One hundred and eighty-two (73%; 95% confidence interval 67-79%) of the cases were HIV-1 antibody positive. The diagnosis of tuberculosis was confirmed by microscopy for acid-alcohol fast bacilli, culture of Mycobacterium tuberculosis, or histology in 74% of all cases. HIV negative and positive cases differed in site of disease: among HIV negative patients 72% had pulmonary disease alone, 16% extrapulmonary disease alone and 12% had both, whereas among HIV positive patients 40% had pulmonary disease alone, 34% extrapulmonary disease alone and 26% both (P < 0.001). HIV negative and positive cases were compared with regard to outcome of diagnostic procedures: 55% of HIV negative cases could be diagnosed at enrollment by sputum smear, but only 35% of HIV positive cases (P < 0.01). Among pulmonary cases confirmed by sputum culture, 76% of HIV negative patients had a positive sputum smear, compared with 57% of HIV positive patients (P = 0.09). Pleural and pericardial disease were difficult to confirm, but culture of pleural fluid was positive in 12/46 HIV positive patients, compared with 0/11 HIV negative patients. Lymph node disease was readily confirmed by biopsy. The tuberculin test was positive in only 30/110 (27%) of HIV positive cases, but in 21/38 (55%) of HIV negative cases (P < 0.01). Mycobacterium tuberculosis was cultured in 57% of HIV negative cases and 54% of HIV positive cases; no atypical mycobacteria were isolated. Initial resistance to isoniazid was present in isolates from 5% of cases with a positive culture.
- Published
- 1993
48. Perinatal transmission of HIV-I in Zambia.
- Author
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Hira SK, Kamanga J, Bhat GJ, Mwale C, Tembo G, Luo N, and Perine PL
- Subjects
- Acquired Immunodeficiency Syndrome mortality, Acquired Immunodeficiency Syndrome transmission, Adolescent, Adult, Blotting, Western, Female, Follow-Up Studies, HIV Antibodies analysis, Humans, Infant, Infant, Newborn, Pregnancy, Pregnancy Outcome, Prognosis, Risk Factors, Zambia epidemiology, HIV Seropositivity transmission, HIV-1 immunology, Maternal-Fetal Exchange, Pregnancy Complications, Infectious
- Abstract
OBJECTIVE--To determine the occurrence of vertical transmission of HIV-I from women positive for the virus and the prognosis for their babies. DESIGN--Women presenting in labour were tested for HIV-I. Their newborn babies were also tested. Women positive for the virus were followed up with their babies for two years. SETTING--Teaching hospital in Lusaka, Zambia. SUBJECTS--1954 Women, of whom 227 were seropositive. Of 205 babies, 192 were positive for HIV-I. After birth 109 seropositive mothers and their babies and 40 seronegative mothers and their babies were available for follow up. MAIN OUTCOME MEASURES--Serological examination of mothers and their babies by western blotting. Birth weight and subsequent survival of babies. Women and babies were tested over two years for signs of seroconversion and symptoms of infection with HIV, AIDS related complex, and AIDS. RESULTS--Of the 109 babies born to seropositive mothers and available for follow up, 18 died before 8 months, 14 with clinical AIDS. Of the 91 remaining, 23 were seropositive at 8 months. By 24 months 23 of 86 surviving babies were seropositive, and a further five infected babies had died, four were terminally ill, 17 had AIDS related complex, and two had no symptoms. The overall rate of perinatal transmission was 42 out of 109 (39%). The overall mortality of infected children at 2 years was 19 out of 42 (44%). Before the age of 1 year infected children had pneumonia and recurrent coughs, thereafter symptoms included failure to thrive, recurrent diarrhoea and fever, pneumonia, candidiasis, and lymphodenopathy. All babies had received live attenuated vaccines before 8 months with no adverse affects. CONCLUSIONS--Vertical transmission from infected mothers to their babies is high in Zambia and prognosis is poor for the babies. Perinatal transmission and paediatric AIDS must be reduced, possibly by screening young women and counselling those positive for HIV-I against future pregnancy.
- Published
- 1989
- Full Text
- View/download PDF
49. Rift Valley fever in Chisamba, Zambia.
- Author
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Watts TE, Tembo G, and Ng'andu NH
- Subjects
- Animals, Cattle, Female, Humans, Male, Rift Valley Fever transmission, Sheep, Zambia, Disease Outbreaks, Rift Valley Fever epidemiology
- Published
- 1984
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