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PubMed2004

The political environment of HIV: lessons from a comparison of Uganda and South Africa.

Considerable interest has arisen in the role of governance or political commitment in determining the success or failure of HIV/AIDS policies in sub-Saharan Africa. During the 1990s, Uganda and South Africa both faced dramatic HIV/AIDS epidemics and also saw transformations to new political systems. However, their responses to the disease differed in many ways. This paper compares and contrasts the ways in which policy environments, particularly government structures, can impede or expedite implementation of effective HIV prevention. Four elements of these environments are discussed--the role of political leadership, the existing bureaucratic system, the health care infrastructure, and the roles assigned to non-state actors. Two common international strategies for HIV prevention, syndromic management of sexually transmitted infections and sexual behaviour change interventions, are examined in relation to these elements in Uganda and South Africa during the mid-to-late 1990s. During this period, Uganda's political system succeeded in promoting behaviour change interventions, while South Africa was more successful in syndromic management efforts. Interactions between the four elements of the policy environment were found to be conducive to such results. These elements are relatively static features of the socio-political environments, so lessons can be drawn for current HIV/AIDS policy, both in these two countries and for a wider audience addressing the epidemic.

Cross-Cultural Comparison↗

PubMed2004

Methods of surveying the incidence and severity of cassava mosaic disease and whitefly vector populations on cassava in Africa: a review.

Field surveys in many cassava growing areas of Africa have assessed the incidence and severity of cassava mosaic disease (CMD), populations of the whitefly vector (Bemisia tabaci), and the distribution of cassava mosaic begomoviruses (CMBs). The methods employed differ greatly between countries and attempts at standardization were made in recent CMD surveys in East and Central Africa, notably in the systemwide Whitefly IPM Project, which provides a paradigm for future work on CMBs and whiteflies on cassava in Africa and also elsewhere. However, there is a need for greater standardization so as to assess the continued expansion of the current CMD pandemic in eastern Africa. Standardized methods will facilitate the collection of reliable data, which can be used to predict future disease spread, develop appropriate management strategies and compare disease development between seasons and locations. In this review, the methods used and the problems encountered during such surveys are discussed and recommendations made on future procedure.

Africa↗

PubMed2004

Phylogenetic studies of influenza B viruses isolated in southern Africa: 1998-2001.

Influenza B viruses isolated in southern Africa during the period from 1998 to 2001 were analysed by sequence analysis of the viral haemagglutinin HA1 subunit and the phylogenetic relationships were determined. Influenza B activity varied considerably in South Africa during the 4-year study period with no activity detected in 2000. Phylogenetic analysis revealed that viruses isolated in 1998 from a localised outbreak in Durban belonged to two distinct sub-lineages. Some of the influenza B viruses isolated throughout South Africa in 1999 as well as several viruses obtained from Mozambique in the same year were closely related to the B/Yamanashi/166/98-like viruses. In contrast, the majority of the 1999 isolates, represented by B/Johannesburg/5/99, exhibited considerable drift from the B/Yamanashi/166/98 stain. The viruses isolated during the 2001 season fell into two sub-lineages, one of which had evolved from the B/Johannesburg/5/99-like viruses and the other which had evolved from the group of viruses that included one of the 1998 Durban isolates. These molecular epidemiological studies reveal a diverse and complex pattern of influenza B virus strains circulating in southern Africa.

Africa, Southern↗

PubMed2005

Mongoose rabies in southern Africa: a re-evaluation based on molecular epidemiology.

Relative to the developed world, rabies has been poorly studied in the vast African continent. The southern African countries of Zimbabwe and South Africa, however, are known to sustain a great diversity of lyssaviruses, with large biological variations amongst genotype 1 (rabies viruses) at present more apparent here than elsewhere on the continent. One recognized biotype of rabies virus in the subcontinent appears to be specifically adapted to a variety of mongooses, belonging to the Viverrinae subfamily (family Herpestidae) and are commonly referred to as viverrid viruses, although the term mongoose rabies would be more correct, considering the taxonomic status of the host species involved. It was our objective to study the genetic relationships of 77 rabies virus isolates of this mongoose biotype, isolated in South Africa and Zimbabwe, towards elucidation of the molecular epidemiology of this interesting group of African viruses. In our study of a 592 nucleotide sequence encompassing the cytoplasmic domain of the glycoprotein and the G-L intergenic region of the viral genomes, we provide the first comprehensive data on the molecular epidemiology of these viruses and indicate a history of extended evolutionary adaptation in this geographical domain. The molecular epidemiological observations reported here are highly unlikely to be limited to the small geographical areas of South Africa and Zimbabwe and illustrate the need for lyssavirus surveillance in the rest of sub-Saharan Africa and throughout the entire continent.

Adaptation, Biological↗

PubMed2004

[Rickettsia africae infection. Three cases confirmed by PCR].

BACKGROUND AND OBJECTIVE: African tick bite fever or Rickettsia africae infection has been recognized as an emerging health problem in the last few years. The aim of this study was to describe 3 cases of Spanish tourists who suffered from R. africae infection after visiting South Africa. PATIENTS AND METHOD: Three patients with a suspected rickettsial disease according to epidemiological and clinical manifestations (fever, eschar and exanthema) were studied. Antibodies against Rickettsia conorii were determined by IFI assays. Semi-nested PCR reactions (rOmpA) and subsequent sequence analysis of the amplified products were also carried out. RESULTS: Epidemiological and clinical aspects of this rickettsiosis are described. For diagnosis of this rickettsial disease, conventional serological assays (IFI) were less useful than semi-nested rOmpA PCR reactions, which showed a sensitivity of 100% in our samples. CONCLUSIONS: Three cases of R. africae infection are reported. PCR and subsequent sequencing of the amplicons are useful for the microbiological confirmation of this type of infection. We must think about African tick-bite fever as a possible diagnosis in patients with a febrile rash after returning from endemic areas.

Adult↗

PubMed2004

Fatal type A botulism in South Africa, 2002.

Although wildfowl and domestic livestock botulism has been recognized as a problem in southern Africa, very few human cases have ever been described in the region. In late February 2002, two siblings aged eight and 12 years developed acute flaccid paralysis and died. Mouse bioassays revealed the presence of type A botulinum toxin in the serum of both children, and in the retrieved remains of the implicated food. The implicated vehicle of the toxin was tinned fish in tomato sauce, commercially produced in South Africa. Type A Clostridium botulinum was cultured from the food. The most likely scenario was that corrosion damage had allowed entry of environmental organisms, including Clostridium botulinum, to the tinned food. This is the first outbreak of human type A botulism in southern Africa to be documented, and the first fatal outbreak described; previous human cases in this region have involved type B botulinum toxin, which tends to produce milder disease. A few other outbreaks elsewhere in Africa have been published, the most extensive being a type E epidemic in Egypt. Commercially tinned products were not involved in any of those outbreaks.

Animals↗

PubMedDate not supplied

Manson Lecture. Meningococcal meningitis in Africa.

This review covers the history of meningococcal meningitis in Africa since epidemics of the infection were first described around 100 years ago. It is possible that an epidemic strain of the meningococcus was introduced into West Africa from the Sudan by pilgrims returning from the Haj around the turn of the century. Since 1905 major epidemics of meningococcal meningitis have occurred in countries of the Sahel and sub-Sahel every few years, culminating in a massive epidemic in which nearly 200,000 cases were reported in 1996. Attempts to control epidemic meningococcal meningitis in Africa by vaccination with meningococcal polysaccharide vaccines have met with only modest success because epidemics can progress with great rapidity and vaccination is often started too late. This situation should be improved as a result of a recent initiative, the International Coordinating Group (ICG), which is contributing to better surveillance in countries at risk and ensuring that vaccine is available when needed. However, in the medium term, the best prospect for the control of meningococcal meningitis in Africa lies in the recent development of polysaccharide-protein conjugate vaccines which, unlike polysaccharide vaccines, are immunogenic in the very young, induce immunological memory and are likely to give long-lasting protection.

Africa↗

PubMed2002

Shadow on the continent: public health and HIV/AIDS in Africa in the 21st century.

Approaches to the prevention and control of the HIV/AIDS epidemic in Africa have been heavily based on early experiences and policies from industrialised countries, where the disease affects specific risk groups. HIV/AIDS has been dealt with differently from other sexually transmitted or lethal infectious diseases, despite being Africa's leading cause of death. In this review, we discuss the evolution of the global response to the epidemic, and the importance of redefining HIV/AIDS in Africa as a public health and infectious disease emergency. We discuss reconsideration of policies and practice around HIV testing and partner notification, and emphasise the need for an increased focus on treatment. Human-rights based approaches to HIV/AIDS prevention might have reduced the role of public health and social justice, which offer a more applied and practical framework for HIV/AIDS prevention and care in Africa's devastating epidemic.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Serological evidence for virus related to simian T-lymphotropic retrovirus III in residents of west Africa.

Serological evidence is presented here suggesting that a virus closely related to simian T-lymphotropic virus type III (STLV-III) infects man in Senegal, west Africa, a region where AIDS or AIDS-related diseases have not yet been observed. 25 sera from Senegalese individuals that were positive for antibodies to HTLV-III by enzyme-linked immunosorbent assay were examined for antibodies to HTLV-III and STLV-III by western blotting. Sera from individuals originating from regions where AIDS has been reported, such as the United States and Burundi (central Africa), reacted best with antigens of HTLV-III, although antibodies that cross-reacted with STLV-III p24 were also detected. Conversely, sera originating from Senegalese people reacted better with STLV-III than with HTLV-III. This was exemplified by the absence of reactivity in sera from both monkeys and Senegalese people to p41, an antigen regularly detected by sera from antibody positive individuals originating from central Africa or from the United States. In contrast sera from central Africa or the United States did not react with p32, the putative envelope transmembrane protein of STLV-III that is regularly detected by sera from both monkeys and antibody-positive Senegalese people. These results suggest that certain healthy Senegalese people have been exposed to a virus that is more closely related to STLV-III than to HTLV-III. The existence and study of such virus variants potentially with differential pathogenicity may provide important information for the development of an AIDS virus vaccine.

Africa, Western↗

PubMed2000

Cassava mosaic virus disease in East Africa: a dynamic disease in a changing environment.

Cassava mosaic disease (CMD), now known to be caused by cassava mosaic geminiviruses (Family Geminiviridae; Genus Begomovirus), was first reported in East Africa in 1894. Epidemics occurred in Madagascar and Uganda in the 1930s and 1940s, and more localised rapid spread of CMD was observed in parts of coastal Tanzania in the 1930s and coastal Kenya in the 1970s. During the 1990s, a major regional pandemic of an unusually severe form of CMD has expanded to affect parts of at least five countries, causing massive economic losses and destabilising food security. Mechanisms responsible for the development and progress of the pandemic have been described, and comparisons of epidemiological data for varieties grown throughout the period under review suggest that the recent pandemic has been characterised by rapid rates of CMD spread hitherto unknown in East Africa. A key factor in the genesis and spread of the pandemic has been the recombination between two distinct cassava mosaic geminiviruses to produce a novel and more virulent hybrid. Although such events may be common, the known history of CMD in East Africa suggests that the frequency with which they become epidemiologically significant is low. A corollary of this is that resistance, developed originally in Tanzania between 1934 and 1960, and utilized and supplemented at the International Institute of Tropical Agriculture, Nigeria, since 1971, is providing effective CMD control in current pandemic-affected areas of East Africa. Consequently, it is concluded that prospects for managing CMD in the 21st century are good, and that the approach adopted should build on the model of collaborative research and implementation that has been established in tackling the current CMD pandemic.

Africa, Eastern↗

PubMed2005

[Malaria vectors: from the field to genetics. Research in Africa].

Only about 60 Anopheline species transmit malaria among more than 3,000 mosquito species recorded in the world. In Africa, the major vectors are Anopheles gambiae,An. arabiensis, An. funestus, An. nili and An. moucheti. They all belong to species complexes or groups of closely related species that are very difficult to set apart on morphological grounds, but which may have highly variable behaviours and vectorial capacities. Understanding this complexity is of major importance in vector control programs or for implementing any public health intervention program such as drugs or vaccine trials. Among the seven species of the complex,Anopheles gambiaes.s. shows a huge chromosomal polymorphism related to adaptation to specific natural or anthropic environments, from equatorial forested Africa to dry sahelian areas. Recent studies conducted in West and Central Africa suggest an incipient speciation into 2 molecular forms provisionally called M and S. A similar evolutionary phenomenon is observed in An. funestus, in which sympatric populations carrying specific chromosomal paracentric inversions showed restricted gene flow. Distribution of species from An. nili group and An. moucheti complex is restricted to more humid regions of Africa. However in some areas these species play the major role in malaria transmission. Comprehensive knowledge of transmission cycles and of behavioural and underlying genetic heterogeneities that exist within and among natural vector populations will thus benefit the whole area of malaria control and epidemiology. Molecular and genetic studies, as well as in depth monitoring of vector biology, have been recently facilitated by advances in functional and comparative genomics, including recent publication of the nearly complete genome sequence of An. gambiae. Challenge for the next years is to answer to the very simple question: why is an insect a vector?

Africa↗

PubMed2005

[HIV management in Africa].

Africa is the continent hardest hit by the HIV pandemic with, according to the WHO for 2004, more than 25 million people infected. Although the mortality and socioeconomic consequences of HIV infection have been visible and predictable, only since 2000 has the catastrophic situation in Africa and other developing areas mobilized international political and medical attention, in view of the impressive results from antiretroviral treatments where they are accessible. The intolerable lack of access to medical care and effective treatments has engendered a fusion of energy and will - political and scientific, local and international - to make HIV treatment available in Africa. Access to treatment must be accompanied by creation of national public health programs and establishment of infrastructures and trained teams. Necessary steps including anticipation and prevention of pitfalls in the large-scale use of antiretrovirals, long-term planning, organization of supplies and distribution, ensuring the permanence of financial support, and making appropriate strategic choices. These steps are required to guarantee the future and to prevent an epidemic rebound due to drug-resistant HIV strains. The conditions of international economic and medical aid have been clarified and are now better adapted to real needs. Nonetheless large disparities still exist according to country and region. The initial results of cohorts of treated patients show results similar to those in the industrialized countries and provide encouragement about the future. Results in countries such as Uganda and Senegal show that local political involvement is primordial for long-term success. Access to antiretroviral drugs is an urgent and essential marker of comprehensive management, but the conditions of their use must be taken into account in assessing future projects if we want to change the course of HIV in Africa.

Africa↗

PubMed1992

The situation in Africa.

More than three million women world-wide are infected with HIV, and women will constitute 40% of the new AIDS cases in 1990-1991. Unlike in the industrialized world, HIV in Africa is heterosexually transmitted and thus affects at least as many women as men. Already the leading cause of death in a major African city, HIV may be spreading to rural areas. In spite of improvement in surveillance, under-reporting makes it difficult to project trends, document differences within and between urban and rural areas, and identify at-risk groups. Increasing evidence shows that STDs play a major role in spreading the HIV epidemic. Male-to-female transmission is more efficient owing to factors related to the pathogen and the host. Ulcerative STDs such as chancroid, syphilis and herpes facilitate HIV entry through mucosal discontinuation and recruitment of HIV target cells. The role of non-ulcerative STDs such as gonorrhoeal, chlamydial and trichomonal infections needs further elucidation. Lack of circumcision, traditional healing practices and oral contraceptives may affect the risk of viral transmission, but may not be major or modifiable risk factors. Pregnancy and pregnancy-associated immune alterations do not seem to affect the clinical course of HIV/AIDS in African women or impair immunocompetence. Maternal HIV can adversely affect pregnancy outcome in Africa, causing low birth-weight, prematurity, intrauterine and intrapartum fetal death. The risk for these outcomes is likely to depend on the degree of immunological and clinical deterioration. Breast-feeding does not appreciably increase the risk of HIV transmission to the infant and should be actively promoted in Africa. Control of HIV/AIDS in Africa, in the absence of an effective vaccine, will focus on behavioural changes through health education and condom use. High frequency STD transmitter core groups, mainly prostitutes and their clients, are currently the target of prevention campaigns which are proving to be successful and affordable.

Africa↗

PubMed1995

Rheumatoid arthritis and connective tissue disorders: sub-Saharan Africa.

Rheumatoid arthritis (RA) once a rarity in Africa, is now reported in large numbers from many parts of Africa. Although epidemiological surveys have shown that the prevalence in urban populations is similar to Western communities, it is less common in rural areas. Further epidemiological studies are needed to confirm these findings in other parts of Africa and identify factors contributing to this difference to provide a better understanding for the emergence of RA in Africa. Earlier reports suggested that in African blacks RA was a mild disease, severe radiographic changes were uncommon, deformities were rare and extra-articular features were unusual and only symptomatic therapy was necessary to control symptoms in most patients. Recent experience shows that severe disease with deformities and radiographic changes are seen and a wide spectrum of extra-articular features are noted although they may be less common than in Caucasians. African blacks with RA may have a younger age of onset and the genetic association with HLA DR4 has been confirmed. Systemic lupus erythematosus (SLE) is also recognized more often in African blacks who have a younger age of onset. SLE is also recognized less often in males. Features such as photosensitivity and serositis are less common while renal disease is more common. A reported short-term mortality of about 30% emphasizes the need for urgent efforts to improve the prognosis in SLE. The infrequent occurrence of localized systemic sclerosis and the absence of anti-centromere antibodies in blacks was noted in a recent large series of patients with systemic sclerosis. The other connective tissue diseases and systemic vasculitides are reported much less frequently and will probably be detected more often in future. Anti-cardiolipin antibodies are detected frequently in association with infections, including HIV infection. The spectrum of diseases associated with ANCA includes a variety of connective tissue diseases and infections such as HIV infection and invasive amoebiasis must be added.

Adult↗

PubMed2003

Rape and HIV post-exposure prophylaxis: addressing the dual epidemics in South Africa.

In South Africa, a country notable for both a rapidly escalating AIDS epidemic and high levels of sexual violence, the issue of HIV post-exposure prophylaxis (PEP) following rape has recently come to the fore, and a policy supporting provision of PEP has been approved by the national government. This paper compares the conditions for providing PEP in Europe and North America with the conditions faced by two initiatives in South Africa, one serving a primarily rural base, and one urban. It is based on a review of the literature on sexual violence in South Africa and use of PEP following occupational and non-occupational exposure. It incorporates perspectives from in-depth interviews in 2000 with 18 key informants, including survivors of sexual violence, gender and HIV activists, domestic violence NGOs, rape crisis centres, physicians, lawyers, researchers and HIV/AIDS advisors in the Department of Health. The paper argues that given the scientific evidence for PEP, and the nature of the dual epidemics of HIV and sexual violence in South Africa, the public health and social justice rationale for implementing PEP equals and indeed exceeds that put forward in industrialised countries. However, delays in accessing PEP caused by the public justice system and lack of training for service providers constitute significant obstacles to effective implementation. In this respect, provision of PEP presents an opportunity to reform and strengthen existing services for post-rape care and to link attention to the epidemic of sexual violence to HIV/AIDS prevention.

Anti-HIV Agents↗

PubMed2004

Abortion law reform in sub-Saharan Africa: no turning back.

Stigma and silence surrounded unsafe abortion in Africa until the International Conference on Population and Development in 1994. Up to five million unsafe abortions are performed in Africa every year, with young women disproportionately affected. This paper summarises the colonial origins of current abortion laws and efforts in the region to provide post-abortion care. Much as it helps to save lives, however, post-abortion care will not eliminate unsafe abortion. There is a need to do away with restrictive laws. The paper describes efforts in several countries to change the law, focusing on Kenya, where organised opposition to reforming the law has emerged and led to the arrest of three service providers. Regional bodies, including the African Union, have taken a stand on abortion within the wider context of safe motherhood and reducing maternal mortality, and advocacy for better abortion laws is increasing across the region. As more girls remain in school and the marriage age increases, the inadequate provision of family planning and abortion care will cause Africa to lose many young women through unsafe sexual activity, unwanted pregnancy, unsafe abortion, early childbearing and HIV infection. The time has come in Africa for a commitment to eliminate deaths and disability from unsafe abortion and respect women's right to decide the number and spacing of their children.

Abortion, Induced↗

PubMed2001

Asthma management and perceptions in rural South Africa.

BACKGROUND: Many First World countries have endeavored to measure the impact of asthma on individuals with asthma and, in addition to this quality of life evaluation, have attempted to define the quality of care for this common chronic illness. OBJECTIVE: The primary objective of this research probe was to assist the National Asthma Program in South Africa with the formulation and delivery of its outreach program to rural asthmatic patients. METHODS: A discussion/questionnaire document was compiled by Partners in Research from established literature. All interviews were conducted in either the clinics, hospitals, or respondents' homes. Both adult asthmatic patients and parents of pediatric asthmatic patients were interviewed. Interviewing took place at seven rural health clinics across South Africa. Each interview included extensive demographic details, questions on asthma definition, symptoms and symptom triggers, family history, age at diagnosis, frequency of symptoms, and treatment. RESULTS: Thirty-five adult asthmatic patients and 27 parents of pediatric asthmatic patients were interviewed. Of the adults, 40% reported wheezing at least once a week (despite diagnosis and treatment) and 19% of children reported similar symptom exacerbations. Fifty-one percent of adults and 56% of children were awakened at least once a week by cough or wheeze. Quality of life measurement reflected that, on average, 37% of responders were frightened during an acute asthma attack, and 68% of parents reported fearing the death of their asthmatic children. Fifty-one percent of adults and 33% of children had been hospitalized at least once for asthma. Although respondents claimed regular training in use of inhaler device, only 43% of adults completed each step correctly. CONCLUSIONS: There is a great deal of fear and ignorance surrounding asthma and, therefore, there is a real need for a greater level of patient education even in the rural areas of South Africa. In rural South Africa, attention should be paid to nurses, because they play a greater role than doctors in management and education of asthma.

Adolescent↗

PubMed2003

Measurement of trends in childhood malaria mortality in Africa: an assessment of progress toward targets based on verbal autopsy.

Reduction of deaths associated with malaria in children is a primary goal of malaria control programmes in Africa, but there has been little discussion about how changes in mortality will be measured. This paper assesses recent historical changes in the contribution of malaria to child survival in Africa by examining data from demographic surveillance systems (DSS) in 25 mainly rural settings. The data were adjusted for the varying sensitivity and specificity of verbal autopsies (VA) in different ranges of malaria mortality and for varying parasite prevalences. Average malaria mortality in the DSS sites in west Africa was 7.8 per 1000 child-years between 1982 and 1998; the rate did not change significantly over this period. In the sites in east and southern Africa combined, malaria mortality was 6.5 per 1000 child-years between 1982 and 1989, but it increased to 11.9 per 1000 child-years between 1990 and 1998. All-cause child mortality and non-malaria mortality, by contrast, decreased significantly over time in both regions; consequently, the proportion of deaths due to malaria rose from 18% to 23% in west African sites and from 18% to 37% in east and southern African sites between 1982-89 and 1990-98. If malaria mortality fell at a rate consistent with the Roll Back Malaria target of halving malaria mortality by the year 2010, an individual DSS of a total population of 63 500 could with adequate VA adjustment detect this reduction after 7 years.

Africa↗