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Caesarean section rate for maternal indication in sub-Saharan Africa: a systematic review.

INTRODUCTION: Rates of caesarean sections in more-developed countries have been rising since 1970, and vary greatly between less-developed countries. Present estimates, based on data from more-developed countries need to be validated with data from less-developed countries. We estimated the need for caesarean section for maternal indication in a population of pregnant women in west Africa (MOMA survey). METHODS: The expected caesarean section rate was calculated from the rate of obstetric risk in the MOMA population, and rates of caesarean section in published work. FINDINGS: Three-quarters of women from hospitals of sub-Saharan Africa were delivered by caesarean section for maternal reasons. Such intervention was needed for six main reasons, protracted labour, abruptio placentae, previous caesarean section, eclampsia, placenta praevia, and malpresentation. Although the observed rate of caesarean section in west African women is 1.3%, our results, combined with those of published work suggest a range of 3.6-6.5% (median, 5.4%). INTERPRETATION: Our method might not be strictly accurate, but it is simple and provides informative findings that can help policy makers and health planners in sub-Saharan Africa to design and follow up programmes to reach the optimum caesarean section rate. Moreover, application of this method to hospital data could improve practitioners' assessments in these countries.

Africa South of the Sahara↗

First 5 years of measles elimination in southern Africa: 1996-2000.

BACKGROUND: Measles is the leading cause of vaccine-preventable death in Africa. Regional measles elimination is considered feasible using current vaccines and a series of WHO-recommended strategies. We aimed to interrupt transmission of measles, and to use case-based surveillance to show the effect of such interruption. METHODS: In southern Africa from 1996, seven countries with a total population of approximately 70 million and with relatively high routine vaccination coverage implemented measles elimination strategies. In addition to routine measles immunisation at 9 months of age, these included nationwide catch-up campaigns among children aged 9 months to 14 years, then follow-up campaigns every 3-4 years among children aged 9-59 months, and the establishment of case-based measles surveillance with serological diagnostic confirmation. RESULTS: Nearly 24 million children aged 9 months to 14 years were vaccinated, with overall vaccination coverage of 91%. Reported clinical measles cases declined from 60000 in 1996 to 117 laboratory-confirmed measles cases in 2000. Reported measles deaths declined from 166 in 1996 to zero in 2000. No increase in adverse events was noted after the measles vaccination campaign. CONCLUSION: A reduction in measles mortality and morbidity can be achieved in very low-income countries, in countries that split their vaccination campaigns by geographical area or by age-group of the target population, and where initial routine measles vaccination coverage among infants was <90%, even when prevalence of HIV/AIDS was extremely high. Continued high-level national commitment will be crucial to implementation and maintenance of proven strategies in southern Africa.

Adolescent↗

Cost-effectiveness of HIV/AIDS interventions in Africa: a systematic review of the evidence.

BACKGROUND: Evidence for cost-effectiveness of interventions for HIV/AIDS in Africa is fragmentary. Cost-effectiveness is, however, highly relevant. African governments face difficult choices in striking the right balance between prevention, treatment, and care, all of which are necessary to deal comprehensively with the epidemic. Reductions in drug prices have raised the priority of treatment, though treatment access is restricted. We assessed the existing cost-effectiveness data and its implications for value-for-money strategies to combat HIV/AIDS in Africa. METHODS: We undertook a systematic review using databases and consultations with experts. We identified over 60 reports that measured both the cost and effectiveness of HIV/AIDS interventions in Africa. 24 studies met our inclusion criteria and were used to calculate standardised estimates of the cost (US$ for year 2000) per HIV infection prevented and per disability-adjusted life-year (DALY) gained for 31 interventions. FINDINGS: Cost-effectiveness varied greatly between interventions. A case of HIV/AIDS can be prevented for $11, and a DALY gained for $1, by selective blood safety measures, and by targeted condom distribution with treatment of sexually transmitted diseases. Single-dose nevirapine and short-course zidovudine for prevention of mother-to-child transmission, voluntary counselling and testing, and tuberculosis treatment, cost under $75 per DALY gained. Other interventions, such as formula feeding for infants, home care programmes, and antiretroviral therapy for adults, cost several thousand dollars per infection prevented, or several hundreds of dollars per DALY gained. INTERPRETATION: A strong economic case exists for prioritisation of preventive interventions and tuberculosis treatment. Where potentially exclusive alternatives exist, cost-effectiveness analysis points to an intervention that offers the best value for money. Cost-effectiveness analysis is an essential component of informed debate about priority setting for HIV/AIDS.

AIDS-Related Opportunistic Infections↗

HIV-1/AIDS and the control of other infectious diseases in Africa.

The effect of HIV-1 on other infectious diseases in Africa is an increasing public health concern. In this review, we describe the role that three major infectious diseases--malaria, sexually transmitted diseases (STDs), and tuberculosis--have had in the HIV-1 epidemic. The high prevalence of untreated STD infections has been a major factor facilitating the spread of HIV-1 in Africa; with the synergistic interaction between HIV-1 transmission and genital herpes being of special concern for control of both diseases. Increased susceptibility to tuberculosis after infection with HIV-1 has led to a rising incidence and threat of increased transmission of tuberculosis. Clinical malaria occurs with an increased frequency and severity in HIV-1-infected individuals, especially during pregnancy. As with tuberculosis, STDs, and other communicable HIV-1-associated diseases, the net effect of HIV-1 might include increased rates of malaria transmission across communities. In addition to enhancing access to HIV-1 prevention and care, public health surveillance and control programmes should be greatly intensified to cope with the new realities of infectious disease control in Africa.

AIDS-Related Opportunistic Infections↗

Tuberculosis in sub-Saharan Africa: opportunities, challenges, and change in the era of antiretroviral treatment.

Rapid scale-up of antiretroviral treatment programmes is happening in Africa, driven by international advocacy and policy directives and supported by unprecedented donor funding and technical assistance. This welcome development offers hope to millions of HIV-infected Africans, among whom tuberculosis is the major cause of serious illness and death. Little in the way of HIV diagnosis or care was previously offered to patients with tuberculosis, by either national tuberculosis or AIDS control programmes, with tuberculosis services focused exclusively on diagnosis and treatment of rising numbers of patients. Tuberculosis control in Africa has yet to adapt to the new climate of antiretroviral availability. Many barriers exist, from drug interactions to historic differences in the way that tuberculosis and HIV are perceived, but failure to successfully integrate HIV and tuberculosis control will threaten the viability of both programmes. Here, we review tuberculosis epidemiology in Africa and policy implications of HIV/AIDS treatment scale-up.

AIDS-Related Opportunistic Infections↗

Rates of complication in first-trimester manual vacuum aspiration abortion done by doctors and mid-level providers in South Africa and Vietnam: a randomised controlled equivalence trial.

BACKGROUND: We assessed whether the safety of first-trimester manual vacuum aspiration abortion done by health-care providers who are not doctors (mid-level providers) is equivalent to that of procedures done by doctors in South Africa and Vietnam, where mid-level providers are government trained and accredited to do first-trimester abortions. METHODS: We did a randomised, two-sided controlled equivalence trial to compare rates of complication in abortions done by the two groups of providers. An a-priori margin of equivalence of 4.5% with 80% power and 95% CI (alpha=0.05) was used. 1160 women participated in South Africa and 1734 in Vietnam. Women presenting for an induced abortion at up to 12 weeks' gestation were randomly assigned to a doctor or a mid-level provider for manual vacuum aspiration and followed-up 10-14 days later. The primary outcome was complication of abortion. Complications were recorded during the abortion procedure, before discharge from the clinic, and at follow-up. Per-protocol and intention-to-treat analyses were done. This trial is registered at with the identifier . FINDINGS: In both countries, rates of complication satisfied the predetermined statistical criteria for equivalence: rates per 100 patients in South Africa were 1.4 (eight of 576) for mid-level providers and 0 for doctors (difference 1.4, 95% CI 0.4 to 2.7); in Vietnam, rates were 1.2 (ten of 824) for mid-level providers and 1.2 (ten of 812) for doctors (difference 0.0, 95% CI -1.2 to 1.1). There was one immediate complication related to analgesics. Delayed complications were caused by retained products and infection. INTERPRETATION: With appropriate government training, mid-level health-care providers can provide first trimester manual vacuum aspiration abortions as safely as doctors can.

Abortion, Induced↗

Effect of a structural intervention for the prevention of intimate-partner violence and HIV in rural South Africa: a cluster randomised trial.

BACKGROUND: HIV infection and intimate-partner violence share a common risk environment in much of southern Africa. The aim of the Intervention with Microfinance for AIDS and Gender Equity (IMAGE) study was to assess a structural intervention that combined a microfinance programme with a gender and HIV training curriculum. METHODS: Villages in the rural Limpopo province of South Africa were pair-matched and randomly allocated to receive the intervention at study onset (intervention group, n=4) or 3 years later (comparison group, n=4). Loans were provided to poor women who enrolled in the intervention group. A participatory learning and action curriculum was integrated into loan meetings, which took place every 2 weeks. Both arms of the trial were divided into three groups: direct programme participants or matched controls (cohort one), randomly selected 14-35-year-old household co-residents (cohort two), and randomly selected community members (cohort three). Primary outcomes were experience of intimate-partner violence--either physical or sexual--in the past 12 months by a spouse or other sexual intimate (cohort one), unprotected sexual intercourse at last occurrence with a non-spousal partner in the past 12 months (cohorts two and three), and HIV incidence (cohort three). Analyses were done on a per-protocol basis. This trial is registered with ClinicalTrials.gov, number NCT00242957. FINDINGS: In cohort one, experience of intimate-partner violence was reduced by 55% (adjusted risk ratio [aRR] 0.45, 95% CI 0.23-0.91; adjusted risk difference -7.3%, -16.2 to 1.5). The intervention did not affect the rate of unprotected sexual intercourse with a non-spousal partner in cohort two (aRR 1.02, 0.85-1.23), and there was no effect on the rate of unprotected sexual intercourse at last occurrence with a non-spousal partner (0.89, 0.66-1.19) or HIV incidence (1.06, 0.66-1.69) in cohort three. INTERPRETATION: A combined microfinance and training intervention can lead to reductions in levels of intimate-partner violence in programme participants. Social and economic development interventions have the potential to alter risk environments for HIV and intimate-partner violence in southern Africa.

Adolescent↗

History of salt supplies in West Africa and blood pressures today.

Excess salt consumption has been implicated in the rising prevalence of essential hypertension in West Africa. It has been suggested that low supplies of salt in West African history were responsible for a genetic mutation that predisposes Blacks to high blood pressure. However, historical evidence concerning salt supplies in West Africa suggests that availability was not uniform. For instance, in Senegal and Gambia salt production has been extensive since ancient times, whereas in ancient Nigeria the population had to depend on local vegetables salts or meagre imports of the mineral. Reports that blood-pressures in Senegalese and Gambians are lower than those in Nigerians may be a reflection of historical differences in salt supply. The difference in blood pressure between members of a racial group also casts serious doubt on the concept of racial homogeneity often accepted in the medical sciences, and the relation between blood-pressure and salt availability in West Africa reveals that insights can be obtained from a study of history.

Africa, Western↗

Vector-parasite transmission complexes for onchocerciasis in West Africa.

BACKGROUND: In West Africa, there are two strains of the filarial parasite Onchocerca volvulus, which differ in their ability to induce ocular disease. Transmission studies have suggested that six sibling species of the parasite vector, the black fly Simulium damnosum sensu lato, allow development of the two strains of O volvulus with varying efficiency. We aimed to test the hypothesis of parasite-vector complexes, whereby the two parasite strains, known as forest and savanna, are preferentially transmitted by distinct groups of the species of S damnosum S l. METHODS: During 1993 and 1994, wild black flies were collected from 11 river basins within the area covered by the Onchocerciasis Control Programme (OCP). The flies were dissected and filarial larvae, ovaries, and malpighian tubules removed. Genomic DNA was extracted from larvae, and PCR amplification was used to classify O volvulus parasites as forest or savanna strains. PCR-amplified DNA from ovaries and malpighian tubules was used to distinguish sibling species of S damnosum s l. S yahense and S squamosum were distinguished by body colour. FINDINGS: 214 of 105105 flies dissected were infected with filarial larvae; 84 of these were infected with mature O volvulus parasites. Of the 35 savanna-dwelling infected flies. 17 carried forest-strain parasites and 18 savanna-strain parasites. Of the 45 infected flies identified as the forest dwelling sibling species. 20 carried savanna-strain parasites and 25 forest-strain parasites. No significant differences were found in the numbers of mature larvae of each strain carried by the forest-dwelling species of fly or in the number of forest and savanna larvae in savanna-dwelling vector species. INTERPRETATION: Vector-parasite transmission complexes do not currently play a part in the biology of O volvulus transmission in the area of the OCP in West Africa. This finding has important strategic implications for the future of efforts to control onchocerciasis in West Africa.

Africa, Western↗

Possible aetiological factors in leukaemias in Africa.

The hypothesis that the true incidence of c-ALL is relatively uniform throughout the world is not supported by experience in tropical Africa, where ALL is uncommon under five years of age. A high rate of spontaneous somatic mutation in pre-B cells may initiate the development of c-ALL, but its progress could be determined by (i) a leukaemogenic agent causing a second genetic event, (ii) the effects of intense antigenic barrage, either stimulating or suppressing pre-B-cell mitosis, or (iii) genetic determinants. Epidemiological patterns in populations of low, intermediate and high socio-economic status may be classified I-III with increasing incidence of diagnosed T-ALL in children over five years and c-ALL in younger children, and subclassified A and B with decreasing incidence of BL. There may be two forms of AML, one similar to that seen in industrialized countries, the other occurring at high prevalence in African children of low socio-economic status, often presenting with chloroma, and perhaps associated with immune suppression secondary to malnutrition, malaria and other intercurrent infections. Uncontrolled exposure to petroleum and other chemicals, and the use of alkylating agents in treatment of neoplasms in young patients could emerge as important causes of ANLL in Africa. There are two varieties of CLL also, one similar to that seen in the western world, the other prevalent in adults below 45 years of age, especially women: transmission of a leukaemogenic agent is postulated, to which women are more susceptible due to immunosuppression during normal pregnancy. The human population and some subhuman primates of subSaharan Africa are the largest reservoir of HTLV-1, which shows association with B-CLL over 50 years of age and ATL.

Africa↗

Tuberculosis in Africa: clinical presentation and management.

In the last decade, sub-Saharan Africa has experienced an explosive increase in tuberculosis (TB) cases, largely as a result of the co-epidemic of human immunodeficiency virus (HIV) infection. This article reviews the essential background epidemiology of TB in sub-Saharan Africa. The clinical features and diagnostic problems of pulmonary/extrapulmonary TB in adults and children are discussed, particularly in relation to HIV infection. Different treatment regimens, their cost, adverse reactions, the ways in which HIV infection influences treatment response and the extent of drug resistance are reviewed. The recommended approaches to TB control in Africa, including methods used to prevent TB through Bacillus Calmette-Guerin and chemoprophylaxis are examined. The success achieved by good National TB Control Programmes in some African countries allows cautious optimism that this epidemic can be controlled.

Adult↗

Polymorphisms and mutations found in the regions flanking exons 5 to 8 of the TP53 gene in a population at high risk for esophageal cancer in South Africa.

A previous study in esophageal cancer (EC) patients from South Africa showed that 17% of tumors contained somatic mutations, including small deletions, insertions, and point mutations, resulting in frameshifts or amino acid changes in exons 5-8 of the TP53 gene. In the present study, polymerase chain reaction single-strand conformation polymorphism and DNA sequence analysis were used to search for sequence variation in the regions flanking exons 5-8 in a series of 74 primary human esophageal squamous cell carcinomas (ESCC). DNA from blood from 37 of the same EC patients and 118 blood samples from the same ethnic group, originating from the Transkei region of South Africa, a high-risk area for EC, served as controls. Mutations were rarely found in the regions flanking exons 5-8, but polymorphisms were frequent. Two mutations (G-->A, codon 331; G-->T, donor splice site) were found in the exon 9 region, while four polymorphisms occurred in intron 3 (16 bp duplication) and exon 4 (C-->A, codon 34; G-->C, codon 36; G-->C, codon 72) regions. Loss of heterozygosity occurred for the 16 bp polymorphism in the EC patients, but not in the controls. Certain genotypes were common in the EC group while others were common in the control group. Graphic representation illustrates the various mutations/polymorphisms found in the TP53 gene in samples from EC patients from South Africa. The results indicate that various small deletions and insertions occur at direct repeat sequences and can be explained by slipped mispairing. The point mutations include the polymorphism in codon 72 (Arg-->Pro), which has recently been associated with an increased risk of developing human papilloma virus-associated cancers.

Black People↗

Radiation therapy in Africa: distribution and equipment.

BACKGROUND AND PURPOSE: Africa is the least developed continent as regards radiation oncology resources. The documented ASR of cancer is of the order of 1 to 2 per 1000. With improving health care this is becoming more significant. This review was undertaken to help develop priorities for the region. MATERIALS AND METHODS: Radiation Oncology departments in Africa were identified and a survey of their equipment performed. These were compared to the reported situation in 1991. Population tables for the year 2000 were compared to available megavoltage machines. RESULTS: Of 56 countries in Africa, only 22 are confidently known to have megavoltage therapy concentrated in the southern and northern extremes of the continent. The 155 megavoltage machines operating represents over 100% increase over the past 8 years. The population served by each megavoltage machine ranges from 0.6 million to 70 million per machine. Overall, only 50% of the population have some access to Radiation Oncology services. CONCLUSION: Progress has been made in initiating radiation oncology in Ghana, Ethiopia and Namibia. There has been some increase in machines in Algeria, Egypt, Libya, Morocco and Tunisia. However, a large backlog exists for basic radiation services.

Africa↗

Genetic heterogeneity of bovine viral diarrhoea viruses isolated in Southern Africa.

Seventy three field isolates of bovine viral diarrhoea virus (BVDV), obtained from cattle in Mozambique and South Africa, were characterised by comparative nucleotide sequence analysis of part of the 5' non-coding region (5'NCR) of the viral genome. The target region was amplified by reverse transcription-polymerase chain reaction (RT-PCR). The amplicons were cloned in pUC 19 plasmid and both strands were sequenced by T7 polymerase dideoxynucleotide chain-termination sequencing or directly by cycle sequencing. The 245 base pair (bp) nucleotide sequences, derived from the 5'NCR, were aligned and compared to the corresponding positions of published sequences of BVDV type I and II strains and of pestiviruses of ovine and porcine origin. The phylogenetic trees, generated from those comparisons, allowed the Southern African isolates to be assigned to two main groups within the BVDV I genotype. Group A could be subdivided into three clusters, two of which grouped with BVDV strains of European and American origin. The third cluster did not group with any known BVDV I strains and it was confirmed in a comparison from the NS3 coding region. Group B contained more divergent isolates which differed by 18-23%, from BVDV I reference strains NADL, Osloss and SD-1 and comprised another distinct subset within the BVDV I genotype. This grouping was consistent in a comparison involving the NS2-NS3 region. It was concluded that BVD viruses occurring in Southern Africa are genetically diverse, comprising different variants within the BVDV I genotype. They include viruses similar to BVDVs found in Europe and America and others apparently rare or absent in those continents, termed here as BVDV Ic and Id. The co-existence of BVDV strains of European and American origin in certain areas both in Mozambique and South Africa, indicates a probable introduction of those viruses through imports of cattle or through potentially infectious bovine products. In addition, the detection of isolates apparently rare or absent from Europe and America may indicate the presence of African variants of BVDV I (Pestivirus 1).

Africa, Southern↗

A new variant of GB virus C/hepatitis G virus (GBV-C/HGV) from South Africa.

Phylogenetic analysis of the 5' non-coding region (5'NCR) sequences has demonstrated that GB virus C/hepatitis G virus (GBV-C/HGV) can be separated into three major groups that correlate with the geographic origin of the isolate. Sequence analysis of the 5'NCR of 54 GBV-C/HGV isolates from 31 blood donors, 11 haemodialysis patients and 12 patients with chronic liver disease suggests the presence of a new variant of GBV-C/HGV in the province of KwaZulu Natal, South Africa. Eleven isolates grouped as group 1 variants (bootstrap support, 90%) found predominantly in West and Central Africa, a further six isolates grouped as group 2 variants (bootstrap support, 58%) found in Europe and North America; five of which grouped as 2a (bootstrap support, 91%) and one as 2b (bootstrap support, 87%), the latter also includes isolates from Japan, East Africa and Pakistan. Although the remaining 37 GBV-C/HGV isolates were more closely related to group 1 variants (bootstrap support, 90%), they formed a cluster, which was distinct from all other known GBV-C/HGV sequences. None of the South African isolates grouped with group 3 variants described from Southeast Asia. Three variants of GBV-C/HGV exist in KwaZulu Natal: groups 1, 2 and a new variant, which is distinct from other African isolates.

Base Sequence↗

Globalisation and local power: influences on health matters in South Africa.

This paper reviews some of the multiple influences on health issues in South Africa, placing them in the context of globalisation. By examining the complexity of factors, both domestic and global, which impact on these issues, it questions the extent to which global patterns in areas such as health policy, HIV/AIDS, health care pluralism, and neo-liberal macroeconomic policy have played out in South Africa. The identification of some of the multiple and complex forces in each case reveals a relatively consistent story of global pressures interacting with domestic realities, with some recognizably local results. There is no doubt that a full and nuanced understanding of health in South Africa requires an appreciation of developments in the global political economy, international organizations such as the WHO and World Bank, and forces which operate outside of institutions. In each case, however, the specific opportunities available to actors within the country, as well as the relative power of those actors, should be given their due consideration in analysing their potential impact on health matters.

HIV Infections↗

Regional perspectives on influenza surveillance in Africa.

Africa possesses little capacity for influenza surveillance-Senegal and South Africa being the only countries in the WHO African region who regularly pursue active surveillance and characterize influenza isolates. South Africa has three sites-in Cape Town, Durban and the largest in Johannesburg at the National Institute for Virology (NIV). The NIV antigenically and molecularly characterizes influenza viruses isolated from specimens provided by a sentinel network of approximately 50 clinical sites. This information, together with the isolates themselves are supplied to WHO International Influenza Centres in London and Melbourne. In addition, proxy markers of influenza severity such as school absenteeism and doctor/clinic visits are monitored to assess the severity of epidemics. Although, influenza exacts a heavier toll of the illness burden in developing countries already beset with underlying chronic medical conditions and also has a more severe impact on economies largely dependent on single income earners and subsistence farmers, influenza surveillance and vaccination awareness is woefully lacking on the African continent, and this urgently needs to be remedied.

Animals↗

Hepatitis A shifting epidemiology in the Middle East and Africa.

Data on the endemicity of hepatitis A virus (HAV) infection in Africa and the Middle East are scant, but most of Africa appears to remain a high endemicity region, with the exception of subpopulations in some areas, e.g. White people in South Africa. Saudi Arabia is a model for the Middle East, and is a country in which shifting HAV epidemiology has been documented in recent years, concurrent with the social and economic development that has occurred over the last two decades. Earlier studies generally showed very high prevalence rates, with most people becoming infected in early childhood. Between 1989 and 1995, however, there was a significant fall in the seroprevalence of antibodies to HAV in children up to 12 years old throughout the country except in one region bordering the Yemen. The highest seroprevalence is found in children from rural backgrounds, while the seroprevalences in Bedouin and urban children are similar. Seroprevalence is related to socioeconomic status, being highest in the lowest groups. Similar findings have been reported from other countries in the Middle East. The existence of pockets of high endemicity for HAV infection with surrounding areas shifting towards intermediate endemicity may lead to outbreaks, and widespread vaccination should be considered.

Adolescent↗