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PubMed1989

Regional prevalence of hepatitis B, delta, and human immunodeficiency virus infection in southern Africa: a large population survey.

Although hepatitis B infection is endemic in southern Africa, a changing epidemiology of the disease has recently been documented in the region. The authors surveyed migrant southern African male mineworkers during 1986 to establish the prevalence of chronic hepatitis B and D (delta) infection in their areas of origin. Hepatitis B surface antigen (HBsAg) was tested in 29,312 adult male mineworkers from 18 geographic regions, encompassing the diverse tribal and linguistic groups in the region, as well as in expatriate mineworkers from neighboring southern African countries. The same cohort was also tested for antibody to human immunodeficiency virus (HIV). Selected hepatitis B carriers were also tested for hepatitis B virus deoxyribonucleic acid (DNA), antibody to hepatitis D (anti-HD), and alpha-fetoprotein. The overall prevalence of HBsAg in this survey was 9.9%. However, the prevalence varied from 5.5% to 14% in different ethnic groups. A minority of carriers (4.9%) had replicative hepatitis B infection and were hepatitis B virus DNA-positive. Only 0.6% of tested carriers were anti-HD-positive. Alpha-fetoprotein determinations were abnormal in 1.2% of hepatitis B-positive men. These data show that although chronic hepatitis B infection remains widespread in southern Africa, carrier rates vary significantly from region to region. In contrast, hepatitis D co-infection remains extremely uncommon. These baseline seroprevalence data also establish that HIV infection was, in 1986, a rare infection in the indigenous population of South Africa.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Seroprevalence of HIV infection in rural South Africa.

OBJECTIVES: To establish the prevalence of HIV infection in rural South Africa and to investigate demographic factors that influence this prevalence. DESIGN: An anonymous HIV seroprevalence survey was performed in conjunction with a population-based malaria surveillance programme. SETTING: The rural area of northern Natal/KwaZulu, South Africa. PARTICIPANTS: A total of 5023 black African participants were recruited by malaria surveillance agents during house-to-house visits; each house in an endemic malaria area is visited approximately once every 6 weeks. Participants included 4044 healthy and 979 febrile individuals (i.e., suspected of having malaria). MAIN OUTCOME MEASURES: HIV-1 and HIV-2 serological status, degree of mobility, age and sex. RESULTS: Sixty of the 5023 blood specimens were confirmed to be HIV-1-antibody-positive by Western blot, an overall prevalence of 1.2% (95% confidence interval, 0.9-1.5). None of the specimens was positive for HIV-2 antibodies. After adjusting for age, presence of fever and migrancy, women had a 3.2-fold higher prevalence of HIV-1 infection than men. HIV-1 infection was approximately three times more common among subjects who had changed their place of residence recently (2.9 versus 1.0%, P < 0.01). CONCLUSIONS: The prevalence of HIV-1 infection is higher among women than men resident in rural Natal/KwaZulu, South Africa. This is at least in part the result of oscillatory migration, particularly of men who work in urban areas but have families and homes in rural areas. Migration is associated with a higher prevalence of HIV-1 infection, suggesting that improving social conditions so that families are not separated and become settled in their communities is one way to help reduce the spread of HIV-1.

Adolescent↗
PubMed1997

Comparison of cost effectiveness of directly observed treatment (DOT) and conventionally delivered treatment for tuberculosis: experience from rural South Africa.

OBJECTIVE: To conduct an economic evaluation of directly observed treatment (DOT) and conventionally delivered treatment for the management of new cases of tuberculosis in adults. DESIGN: Community based directly observed treatment, which has been implemented in the Hlabisa district of South Africa since 1991, was compared with a conventional approach to tuberculosis treatment widely used in Africa. Each was assessed in terms of cost, cost effectiveness, and feasibility of implementation within existing resource constraints. SETTING: Hlabisa Health District, South Africa. SUBJECTS: Adult patients with new cases of tuberculosis on smear testing; the number of cases increased from 20 per month to over 100 from 1991 to 1996. MAIN OUTCOME MEASURES: Cost of case management in 1996, cost effectiveness in terms of the cost per case cured, and bed requirements in comparison with bed availability for the 1990, 1993, and 1996 caseload. Costs are expressed in US dollars at values for 1996. RESULTS: Directly observed treatment was 2.8 times cheaper overall than conventional treatment ($740.90 compared with $2047.70) to deliver. Directly observed treatment worked out 2.4-4.2 times more cost effective, costing $890.50 per patient cured compared with either $2095.60 (best case) or $3700.40 (worst case) for conventional treatment. The 1996 caseload of tuberculosis required 47 beds to be dedicated to tuberculosis to implement directly observed treatment, whereas conventionally delivered treatment would have required 160 beds; the current number of beds for tuberculosis treatment in Hlabisa is fixed at 56. CONCLUSIONS: Because of the reduced stay in hospital, directly observed treatment is cheaper, more cost effective, and more feasible than conventional treatment in managing tuberculosis in Hlabisa, given the existing hospital bed capacity and the escalating caseload due to the HIV/AIDS epidemic. Such results may hold elsewhere, and wherever conventional tuberculosis management is practised a switch to directly observed treatment will increase hospital capacity to cope with a growing caseload.

Adult↗
PubMed1994

Impact of conflict on demographic factors and their importance in negotiated settlement in southern Africa.

"Though the concept of negotiated settlements gained its momentum in southern Africa--Angola, Mozambique, Namibia and South Africa--the full success of negotiations is yet to be seen in most of these countries.... Demographic consequences of conflicts are explained through a systemic model. The importance of demographic variables on negotiated settlement has also been explained the same way. There is no easy way out to overcome conflicts...but it is suggested that mutual consultation with opposition parties or minorities, or the suppressed people, would help ease many situations in Africa or elsewhere."

Africa↗
PubMed1997

Development of an HIV clinical and research database for South Africa.

Health service restructuring in South Africa provides an opportunity to introduce appropriate Health Information System (HIS) technology. This is particularly relevant given the emerging HIV epidemic and the need to capture, translate and disseminate new experiences in HIV/AIDS care, support and clinical research. In 1994, a number of clinicians and health-care providers working in South Africa had begun to establish basic computerized databases to assist in research on HIV, but no standardized nomenclature or framework for collaboration was created. This paper describes a clinical and research database that could be used as an example for a standardized system by clinicians working in South Africa. The authors, with assistance from the National AIDS Research Programme of the Medical Research Council, created a prototype relational database using Microsoft Access. To test the prototype, 1057 HIV-positive patients from the infectious Disease Clinic at Johannesburg General Hospital were entered.

Databases, Factual↗
PubMed2005

Private sector, human resources and health franchising in Africa.

In much of the developing world, private health care providers and pharmacies are the most important sources of medicine and medical care and yet these providers are frequently not considered in planning for public health. This paper presents the available evidence, by socioeconomic status, on which strata of society benefit from publicly provided care and which strata use private health care. Using data from The World Bank's Health Nutrition and Population Poverty Thematic Reports on 22 countries in Africa, an assessment was made of the use of public and private health services, by asset quintile groups, for treatment of diarrhoea and acute respiratory infections, proxies for publicly subsidized services. The evidence and theory on using franchise networks to supplement government programmes in the delivery of public health services was assessed. Examples from health franchises in Africa and Asia are provided to illustrate the potential for franchise systems to leverage private providers and so increase delivery-point availability for public-benefit services. We argue that based on the established demand for private medical services in Africa, these providers should be included in future planning on human resources for public health. Having explored the range of systems that have been tested for working with private providers, from contracting to vouchers to behavioural change and provider education, we conclude that franchising has the greatest potential for integration into large-scale programmes in Africa to address critical illnesses of public health importance.

Acute Disease↗
PubMed2004

Ophthalmological observations made during the mid-19th-century European encounter with Africa.

European travelers in Africa in the mid-19th century encountered environments quite unlike those of their native lands. These provided many new and unanticipated health challenges. The ophthalmological consequences of exposure to such climates, as recorded incidentally in travelogues, are of potential interest. In this article, the almost contemporaneous narratives of 3 travelers with considerable medical training, David Livingstone and his sometime companion John Kirk, who journeyed in southern Africa, and Gustav Nachtigal, who traveled in northern Africa, are examined for information on ophthalmological problems, both observed and personally experienced. This affords an opportunity to compare observations made in Saharan and sub-Saharan Africa.

Africa↗
PubMedDate not supplied

Tuberculosis and HIV infection in sub-Saharan Africa.

OBJECTIVES: To review the epidemiologic, clinical, and pathological characteristics and the public health implications of human immunodeficiency virus (HIV)-associated tuberculosis in sub-Saharan Africa. DATA SOURCES: Published medical literature (English and French) and proceedings of international and African conferences on the acquired immunodeficiency syndrome (AIDS). STUDY SELECTION: Selection by the authors of articles most pertinent to HIV infection and tuberculosis in Africa and internationally. DATA EXTRACTION: Direct reporting of quantitative data (eg, HIV seroprevalence levels) and of qualitative descriptions and conclusions from selected literature. DATA SYNTHESIS: High rates (20% to 67%) of HIV infection in patients with tuberculosis have been reported from East, West, Central, and Southern Africa. An increase in tuberculosis cases has been reported at the same time as the emergence of AIDS in several countries. Autopsies in Abidjan, Ivory Coast (Côte d'Ivoire), have shown tuberculosis as the most frequent opportunistic infection in patients dying of AIDS. Clinical differences in patients with tuberculosis who were HIV-positive and HIV-negative are reviewed, the most important being a greatly increased mortality rate in HIV-associated disease. Access to HIV testing is required for firm diagnosis, for clinical care and counseling, and for public health surveillance. CONCLUSIONS: The epidemiology of tuberculosis has been profoundly influenced by the epidemic of HIV infection in sub-Saharan Africa. Greatly increased human and material resources are required for this neglected problem in international health.

Acquired Immunodeficiency Syndrome↗
PubMed2006

Adherence to antiretroviral therapy in sub-Saharan Africa and North America: a meta-analysis.

CONTEXT: Adherence to antiretroviral therapy is a powerful predictor of survival for individuals living with human immunodeficiency virus (HIV) and AIDS. Concerns about incomplete adherence among patients living in poverty have been an important consideration in expanding the access to antiretroviral therapy in sub-Saharan Africa. OBJECTIVE: To evaluate estimates of antiretroviral therapy adherence in sub-Saharan Africa and North America. DATA SOURCES: Eleven electronic databases were searched along with major conference abstract databases (inclusion dates: inception of database up until April 18, 2006) for all English-language articles and abstracts; and researchers and treatment advocacy groups were contacted. Study Selection and Data Abstraction To best reflect the general population, studies of mixed populations in both North America and Africa were selected. Studies evaluating specific populations such as men only, homeless individuals, or drug users, were excluded. The data were abstracted in duplicate on study adherence outcomes, thresholds used to determine adherence, and characteristics of the populations. A random-effects meta-analysis was performed in which heterogeneity was examined using multivariable random-effects logistic regression. A sensitivity analysis was performed using Bayesian methods. DATA SYNTHESIS: Thirty-one studies from North America (28 full-text articles and 3 abstracts) and 27 studies (9 full-text articles and 18 abstracts) from sub-Saharan Africa were included. African studies represented 12 sub-Saharan countries. Of the North American studies, 71% used patient self-report to assess adherence; this was true of 66% of the African assessments. Studies reported similar thresholds for adherence monitoring (eg, 100%, >95%, >90%, >80%). A pooled analysis of the North American studies (17,573 patients total) indicated a pooled estimate of 55% (95% confidence interval, 49%-62%; I2, 98.6%) of the populations achieving adequate levels of adherence. Our pooled analysis of African studies (12,116 patients total) indicated a pooled estimate of 77% (95% confidence interval, 68%-85%; I2, 98.4%). Study continent, adherence thresholds, and study quality were significant predictors of heterogeneity. Bayesian analysis was used as an alternative statistical method for combining adherence rates and provided similar findings. CONCLUSION: Our findings indicate that favorable levels of adherence, much of which was assessed via patient self-report, can be achieved in sub-Saharan African settings and that adherence remains a concern in North America.

Africa South of the Sahara↗
PubMed1999

Seroepidemiological study of genogroup I and II calicivirus infections in South and southern Africa.

Diarrhoea is associated with the daily death of between 180 and 200 children under the age of 5 years in South Africa. Until recently, many cases and outbreaks of diarrhoea were not associated with a known aetiologic agent. Previous studies using baculovirus-expressed Norwalk virus (NV) and Mexico virus (MxV) capsid antigens have shown that human calicivirus infection is common in South Africa. In this study, our surveillance was extended to different populations, as well as to four other southern African countries: Namibia, Angola, Zimbabwe, and Mozambique. More than 1,700 specimens, some involved in previous cohort studies of infectious diseases, were enrolled in the surveillance. The overall seroprevalence of antibody against NV was >90% for all cohorts except for Mozambican refugees that had 83. 8% sero-positivity. The MxV antibody prevalence was higher than NV, with >95% positivity for all cohorts, except for one in Namibia that had 81% exposure. This study is one of only a few reporting on the concurrent incidence of NV and MxV infections in a cohort study, and has determined that small round structured viruses are prevalent in the local populations of South and Southern Africa. These agents may account for a number of previously unknown or unidentified causes of diarrhoeal illness, in both adults and children, in southern Africa.

Adolescent↗
PubMed2005

Breast cancer in sub-Saharan Africa: how does it relate to breast cancer in African-American women?

BACKGROUND: African-American women have had a lower incidence, yet higher mortality rate from breast cancer compared with White-American women. African-American women also have had a higher risk for early-onset, high-grade, node-positive, and hormone receptor-negative disease. Similar features have characterized hereditary breast cancer, prompting speculation that risk factors could be genetically transmitted. Further evaluation of this theory required the study of breast cancer among women from sub-Saharan Africa because of their shared ancestry with African-American women. METHODS: Publications from 1988 to 2004 of English-language literature on breast cancer in Africa were reviewed. RESULTS: Women from sub-Saharan Africa were found to have a low incidence of breast cancer. This was partly explained by a largely protective reproductive history, including late menarche, early menopause, high parity with prolonged breastfeeding, irregular menses, and fewer ovulatory cycles. The average age at diagnosis, however, was approximately 10 years younger than breast cancer patients of western nations, and disease stage distribution was shifted toward more advanced disease, which resulted in higher mortality rates. These features were found to be similar to data on breast cancer in African-American women. Mutations in BRCA1 and BRCA2 have been reported in African-American women, but the extent of the contribution of BRCA1 and BRCA2 to breast cancer burden in Africa was uncertain. Limited financial resources lead to suboptimal cancer data collection, as well as delayed diagnosis and treatment of many African breast cancer patients. CONCLUSIONS: Parallels between breast cancer burdens of African-American and sub-Saharan-African women were provocative, indicating the need for further exploration of possible genetically transmitted features related to estrogen metabolism and/or breast cancer risk.

Africa South of the Sahara↗
PubMedDate not supplied

Convergence of behaviour change models for AIDS risk reduction in sub-Saharan Africa.

There is increasing programme focus on the impact of HIV and AIDS and the advances in biomedical research that are taking central stage even in sub-Saharan Africa. Perhaps out of frustration, communication and behaviour change efforts are receiving lesser attention. But as long as heterosexual intercourse remains the predominant means of transmission of HIV in sub-Saharan Africa, there is the inherent danger of more people getting infected thus mopping up the gains from other approaches. This paper therefore argues for evidence based behaviour change interventions in sub-Saharan Africa, revisits the behaviour change theories and their relevance to the African situation. It proposes an integration of models based on the convergence of three existing theories of social learning, diffusion of innovation and social networks and the author's understanding of some African culture. The beauty of the model is based on the fact that 'social norms are best understood and influenced at the level of social networks'; existing chains of communication and the naturalness of exchange of information. A case is made for application of the 'model' to precipitate sexual behaviour change and HIV reduction in sub-Saharan Africa.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Molecular epidemiological analysis of community circulating respiratory syncytial virus in rural South Africa: Comparison of viruses and genotypes responsible for different disease manifestations.

Human respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infection in children in both the industrialized and developing world. Most molecular epidemiological studies have, until now, focused on isolates from hospitalized infants in industrialized countries. Limited data have been available with regard to community circulating RSV, especially from Africa. The present study compares RSV isolates from infants attending rural community clinics in the Northern province of South Africa, with isolates from hospitalized infants in Soweto, near Johannesburg, South Africa, during the same period. A multiplex nested polymerase chain reaction was developed for analyzing the clinical specimens, a technique that permits subtyping and nucleotide sequence analysis of the second variable region of the G-protein gene. Community- and hospital-based isolates from young children in South Africa, as well as isolates from Mozambique were compared phylogenetically. One subgroup B community isolate was identified that had a G-protein truncated by approximately 35 amino acids, however, the other community isolates were not significantly different from hospital isolates. Evidence was found that the same RSV genotypes and viruses could cause mild upper respiratory tract infections or lower respiratory tract infections or severe RSV in young infants.

Amino Acid Sequence↗
PubMed1994

Genetic analysis and molecular phylogeny of simian T-cell lymphotropic virus type I: evidence for independent virus evolution in Asia and Africa.

Type C retroviruses, designated simian T-cell lymphotropic virus type I (STLV-I), have been isolated from several genera of Old World monkeys and apes, but not from New World monkeys and prosimians. To determine the genomic diversity and molecular evolution of STLV-I and to clarify their genetic relationship to human T-cell lymphotropic virus type I (HTLV-I), we enzymatically amplified, then directly sequenced selected regions of the gag, pol, env, and pX genes of STLV-I strains from Asia and Africa. STLV-I strains Si-2, Matsu, and JM86 from Japanese macaques, which exhibited sequence similarities ranging from 98.5 to 99.8% among themselves, diverged by 12.9 to 13.3% from STLV-I strain MM39-83 from a naturally infected rhesus macaque, by 9.7 to 11.2% from STLV-I strains from Africa, and by 8.8 to 11.2% from HTLV-I strains originating in Japan, India, Africa, the Caribbean, the Americas, Polynesia, and Melanesia. By contrast, the interspecies nucleotide sequence similarity among African STLV-I strains from green monkey, yellow baboon, sooty mangabey, and common chimpanzee was remarkably high, ranging from 96.9 to 97.4%, and these STLV-I strains diverged by only 2.2 to 2.8% from HTLV-I strain EL from equatorial Zaire. Phylogenetic trees constructed by using the neighbor-joining and maximum parsimony methods indicated that the Asian STLV-I strains diverged from the common ancestral virus prior to African STLV-I and cosmopolitan and Melanesian HTLV-I strains. Thus, our data are consistent with an archaic presence of STLV-I in Asia, probably predating macaque speciation, with subsequent independent virus evolution in Asia and Africa.

Africa↗
PubMed1996

Genetic relatedness of Sindbis virus strains from Europe, Middle East, and Africa.

The relatedness of 40 strains of Sindbis virus (SIN) from Europe, the Middle East, and Africa was investigated by limited sequencing within the gene encoding the E2 glycoprotein corresponding to amino acid residues 117 to 229 and encompassing one of the major neutralization epitopes. Phylogenetic analyses using distance matrix and parsimonious methods identified two major genetic clusters of western SIN strains, although the variability was less than that of the corresponding region for Venezuelan equine encephalomyelitis virus with a maximum divergence of 12.4% versus 28.5%, respectively. One cluster comprising 19 strains included the HR derivate of the Egypt SIN prototype, AR339, and strains from Israel, Saudi-Arabia, Italy, Slovak Republic, Azerbaijan, as well as three Swedish strains. Another cluster of 17 strains included the Ockelbo virus (OCK) prototype, Edsbyn 5/82, and the majority of SIN strains from northern Europe including strains from Sweden, Norway, and Karelia, as well as two strains from South Africa. A third cluster, supported by the Neighbor joining method, was made up of four strains from South Africa, Uganda, and Cameroon. Residue 212, either Ser or Thr, previously appointed important for the differences in neutralization assays between SIN and Edsbyn 5/82, respectively, correlated with the two major genetic clusters, but was a Thr for two of the three Swedish strains in the SIN prototype cluster, and a Ser in one Swedish and one Karelian strain in the OCK cluster. The finding of strains similar to prototype SIN in Middle Sweden and of strains in South Africa relating to the northern cluster of SIN strains supports the notion of the dispersal of SIN by migrating birds as previously suggested for New World alphaviruses.

Africa↗
PubMed1996

Genetic variation in yellow fever virus: duplication in the 3' noncoding region of strains from Africa.

The nucleotide sequences of three regions of the genomes of 13 yellow fever (YF) virus isolates were determined to define genetic variation and evolution of the virus. Phylogenetic trees generated from sequences of either the 5' terminal 1320 nucleotides of the genome, 754 nucleotides from the NS4A and NS4B genes, or the 3' terminal 511 nucleotides were very similar and contained minor differences. Overall, these results suggested that there were at least four major genotypes of YF virus, including one in Central/East Africa, one in West Africa, and two in South America. Examination of the 3' noncoding region (3'NCR) showed that only West African strains had a 3'NCR of 511 nucleotides while strains from Central/East Africa and South America had shorter 3'NCRs (443-469 nucleotides) due to the absence of YF specific repeat sequences (RYFs). Central/East African strains have two RYFs and West African strains have three RYFs while South American strains only have one copy of the RYF. It is speculated that duplication of the RYF took place in West Africa subsequent to the presumed introduction of YF virus into South America. Thus, both tick-borne (Mandl et al., J. Virol. 65, 4070-4077, 1991 and Wallner et al., Virology 213, 169-178, 1995) and mosquito-borne flaviviruses have variable 3'NCRs.

Africa↗
PubMed1987

Non-A, non-B fulminant viral hepatitis in France in returnees from Asia and Africa.

Among 61 patients admitted for non-A, non-B fulminant viral hepatitis to Hôpital Beaujon, 10 had returned from Asia or Africa, and 51 had not been outside France, within the month preceding jaundice. This suggests that hepatitis might have been contracted in Asia or Africa in the former, and in France in the latter. The interval between the onset of jaundice and the onset of hepatic encephalopathy was 10 days in the former and 26 days in the latter (P less than 0.03). The serum of the patient returning from Asia contained, and the sera of the nine patients returning from Africa did not contain, antibodies to a virus isolated from the stools of patients suffering from an epidemic fecal-oral non-A, non-B viral hepatitis in Central Asia. It is concluded that infection with Asian-African non-A, non-B viruses can be the cause of fulminant hepatitis in persons returning from these countries, that the course of this type of non-A, non-B fulminant viral hepatitis is shorter than that of non-A, non-B fulminant hepatitis contracted in France, and that different viruses might be responsible for non-A, non-B hepatitis in Asia and Africa.

Adult↗
PubMed1996

Wildlife, people and development: veterinary contributions to wildlife health and resource management in Africa.

Human population pressures, habitat loss, environmental degradation and illegal hunting in Africa have resulted in the loss of biodiversity and near extinction of certain wildlife species. The dilemma for Africa is the balancing of conservation and development. If wildlife is not to become a relic of the past then it must have more than just aesthetic value. It must contribute materially to the well being of people who live close to the resource. In fact, appropriate management of biodiversity would lay the foundations for a more positive future for the rural people of Africa, with the key being the adoption of an active adaptive management philosophy. This paper reviews the issue of sustainable use of wildlife resources and how the Veterinary profession contributes positively to wildlife health management in Africa. These contributions have been through increasing veterinary inputs into wildlife management and research, disease surveillance and prevention, training and education. Wildlife and ecosystems are increasingly having to be managed in order to save and maintain biological diversity. Veterinarians have a crucial role to play towards the maintenance of wildlife health as part of a multi-disciplinary wildlife management team.

Africa↗