Determinants of premature births in two central hospital Harare, Zimbabwe, 2011.

Introduction: Prematurity is a major determinant of neonatal morbidity and mortality in Zimbabwe. Although 8-10% of deliveries are premature , prematurity contributes 33% of neonatal deaths. Identifying local risk factors for prematurity could help incoming up with local intervention and prevention strategies. Design: 1:1 unmatched case control study. Setting: Harare and Parirenyatwa central hospitals maternity units. Subjects: All mothers who delivered in the units June to July 2011. Acase was a mother who had delivered a premature baby and control was a mother who delivered a term baby. Results: We interviewed 188 cases and 188 controls. Independent risk factors for premature delivery were -A previous premature delivery [AOR 3.15 95% CI 1.17 8.49, 4.61] being admitted with a medical complication in pregnancy[AOR 2.15 95% CI 1.18-3.92]. Birth interval > 24 months [AOR 0.26 95% CI 0.12 0.59] being well nourished evidenced by BMI ≥20kg/m [ AOR 0.926 95% CI 0.88 0.97] and MUAC ≥23cm [AOR 0.95 95% CI 0.91 0.95] reduced the risk of premature delivery. HIV test was done on 87% of participants, 12% were positive (66% controls, 33% cases) (p≤0.001). Conclusion: Birth interval < 24 months, previous premature delivery, only one ANC attendance, maternal under nutrition and being hospitalized with complications in pregnancy were associated with premature delivery. There was no association with HIV infection. Efforts should be made to give food supplements to pregnant undernourished women.

Risk factors for mortality in smear-negative tuberculosis suspects: a cohort study in Harare, Zimbabwe.

OBJECTIVE: To investigate mortality rates and risk factors for death among smear-negative tuberculosis (TB) suspects. DESIGN: Cohort study nested within a cluster-randomised trial of community-based active case finding. Smear-negative TB suspects were followed for 12 months, with home tracing where necessary. We calculated mortality rates and used regression analysis to investigate the relationship between clinical characteristics and death. RESULTS: Between February 2006 and June 2007, 1195 smear-negative TB suspects were followed for 1136.8 person-years. Human immunodeficiency virus (HIV) prevalence was 63.3%. During follow-up, 139 participants died (11.6%) and mortality rates remained high throughout; 119 (16.5%) HIV-positive individuals and 13 (3.1%) HIV-negative individuals died (HR = 5.8, 95%CI 3.3-10.4, P < 0.001). Advanced immunosuppression was the main risk factor for death among HIV-positive participants, with CD4 count < 50 cells/µ l associated with a 13-fold increased risk of death. Antiretroviral treatment (ART) was initiated by only 106 (14.7%), with long delays in accessing care. CONCLUSION: HIV-positive smear-negative TB suspects are at high and sustained risk of death. Current guidelines for the management of HIV-infected TB suspects are limited, and this study adds to evidence that specific policies are required to promote earlier HIV and TB diagnosis and reduce delays in ART initiation.

Risk factors associated with cholera in Harare City, Zimbabwe, 2008.

OBJECTIVE: Two suspected cholera cases at Beatrice Road Infectious Diseases Hospital were reported to Harare City Health Department on 14 October 2008 setting in motion investigation and control measures. We determined the extent of the epidemic and risk factors for contracting cholera. METHODS: An unmatched 1:1 case-control study was conducted. CASE: Any resident of Harare City, 2 years and above, with acute watery diarrhoea, with or without vomiting from 30 October 2008 to 01 December 2008. CONTROL: Any resident of Harare City, 2 years and above, neighbour to a case, who did not contract cholera during the same period. RESULTS: From 14 October 2008 to 21 January 2009, 11203 cases were reported with a case fatality rate (CFR) of 3.98%. We interviewed 140 cases and 140 controls. Median age was 28 years (Q1 = 20; Q3 = 37.5) and 28.5 years (Q1 = 23; Q3 = 38) for cases and controls respectively. Having a diarrhoea contact at home [AOR = 12.02; 95% CI (5.46 - 26.44)], having attained less than secondary education [AOR = 4.40; 95% CI (2.28 - 8.48)]; eating cold food [AOR = 4.24; 95% CI (1.53 - 11.70)] were independent risk factors while drinking tap water [AOR = 0.05; 95% CI (0.03 - 0.11)], washing hands after using toilet [AOR = 0.19; 95% CI (0.09 - 0.39)]; eating hot food always [AOR= 0.29; 95% CI (0.17 - 0.49)] were independently protective factors. DISCUSSION: The high CFR may be due to poor case management and staff shortage in treatment camps. Th e cholera outbreak in Harare resulted from poor personal and hygiene practices that occur when water supplies are cut. Lack of water, low knowledge on cholera prevention measures and delays in community health education campaigns contributed to the protracted outbreak. Having a diarrhoea contact at home increases chances of household members acquiring infection. Provision of safe drinking water, community health education, recruitment of staff and training of health workers on cholera case management must be prioritized.

Prevalent infectious tuberculosis in Harare, Zimbabwe: burden, risk factors and implications for control.

SETTING: Harare's high density suburbs. OBJECTIVES: To investigate the burden, duration and risk factors for prevalent tuberculosis (TB) and explore potential control strategies. METHODS: Randomly selected adults had TB culture, symptom screen and human immunodeficiency virus (HIV) serology. Prevalent TB was defined as undiagnosed or still culture-positive. Notification data and HIV prevalence in TB out-patients were used to estimate duration of infectiousness (prevalence/estimated incidence). RESULTS: Among 10 092 participants, 40 (0.40%, 95%CI 0.28-0.54) had prevalent smear-positive TB. HIV (adjusted odds ratio [aOR] 3.1, 95%CI 1.6-6.3, population attributable fraction [PAF] 33%), male sex (aOR 3.1, 95%CI 1.5-6.4, PAF 40%), and overcrowding (PAF 34%) were significant risk factors, with past TB treatment significant for HIV-negative participants only (PAF 7%). Recent household TB contact was not significant (PAF 10%). HIV prevalence was 21.1%; 76.9% of HIV-positive participants were previously untested. Duration of infectiousness was at least 18 weeks in HIV-positive and approximately 1 year in HIV-negative patients. CONCLUSIONS: Overcrowding, male sex and HIV infection were major risk factors for prevalent smear-positive TB. Reducing diagnostic delay may have greater potential to improve the control of prevalent TB than interventions targeted at household contacts, TB treatment outcomes, or TB-HIV interventions under current levels of awareness of HIV status.

Diagnostic accuracy of commercial urinary lipoarabinomannan detection in African tuberculosis suspects and patients.

OBJECTIVE: To evaluate a commercially available antigen capture enzyme-linked immunosorbent assay (ELISA) based on detecting lipoarabinomannan (LAM) in urine for the diagnosis of tuberculosis (TB). DESIGN: Consenting TB suspects and registering TB patients prospectively recruited from three hospitals were asked for two sputum specimens for microscopy and culture, urine for LAM testing and blood for human immunodeficiency virus (HIV) testing, with radiological and clinical follow-up for 2 months. RESULTS: Of 427 participants, complete data were available from 397 (307 adult and 23 adolescent TB suspects, and 67 registering TB patients). HIV prevalence was 77%. TB was diagnosed in 195 (49%), including 161 culture-positive patients, and confidently excluded in 114 (29%) participants. LAM ELISA sensitivity was 44% (95%CI 36-52) for culture-confirmed TB (52% in smear-positive patients). Specificity was 89% (95%CI 81-94). Sensitivity was significantly higher in HIV-related TB (52%, 95%CI 43-62, P < 0.001) compared to HIV-negative TB (21%, 95%CI 9-37). Sensitivity in smear-negative patients was low (28%, 95%CI 13-43) for combined HIV-positive and -negative patients. CONCLUSION: Our findings confirm greater sensitivity of urine LAM detection for HIV-related TB. However, both sensitivity and specificity were suboptimal, suggesting that this version cannot confirm or exclude TB in either HIV-infected or non-infected patients.

Predominance of a single genotype of Mycobacterium tuberculosis in regions of Southern Africa.

SETTING: Zimbabwe and Zambia. OBJECTIVE: To determine the genetic diversity of Mycobacterium tuberculosis strains isolated from tuberculosis (TB) patients in Zimbabwe and Zambia. DESIGN: M. tuberculosis isolates cultured from TB patients presenting at referral hospitals in Zimbabwe and health care clinics in Zambia were characterised by IS6110 genotyping and/or spoligotyping using internationally standardised methods. Genotypic data were compared to those from Cape Town and the SpolDB3.0 database. RESULTS: A predominant group of strains could be identified among 116/246 (47.2%) Zimbabwean isolates by their characteristic IS6110-banding pattern and unique spoligotype signature, where spacers 21-24, 27-30 and 33-36 were deleted. Comparison with strains from Cape Town showed that they were closely related to a family of strains present in 2.3% of Cape Town patients. Comparison of the spoligotypes with those obtained from 114 isolates from Zambia showed that 74 (65%) of these isolates had the same spoligotype signature. Spoligotypes in the SpolDB3.0 database showed that this group of strains was rarely isolated in other parts of the world, but was commonly isolated in Southern Africa. CONCLUSION: A predominant group of strains infecting approximately half of the patients in the study are major contributors to the TB epidemic in this region. We have designated this group of strains the Southern Africa 1 (SAF1) family.