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1.
Cancers (Basel) ; 13(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918470

RESUMO

BACKGROUND: Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in Africa and is linked to Plasmodium falciparum (Pf) malaria infection, one of the most common and deadly childhood infections in Africa; however, the role of Pf genetic diversity is unclear. A potential role of Pf genetic diversity in eBL has been suggested by a correlation of age-specific patterns of eBL with the complexity of Pf infection in Ghana, Uganda, and Tanzania, as well as a finding of significantly higher Pf genetic diversity, based on a sensitive molecular barcode assay, in eBL cases than matched controls in Malawi. We examined this hypothesis by measuring diversity in Pf-serine repeat antigen-5 (Pfsera5), an antigenic target of blood-stage immunity to malaria, among 200 eBL cases and 140 controls, all Pf polymerase chain reaction (PCR)-positive, in Malawi. METHODS: We performed Pfsera5 PCR and sequencing (~3.3 kb over exons II-IV) to determine single or mixed PfSERA5 infection status. The patterns of Pfsera5 PCR positivity, mixed infection, sequence variants, and haplotypes among eBL cases, controls, and combined/pooled were analyzed using frequency tables. The association of mixed Pfsera5 infection with eBL was evaluated using logistic regression, controlling for age, sex, and previously measured Pf genetic diversity. RESULTS: Pfsera5 PCR was positive in 108 eBL cases and 70 controls. Mixed PfSERA5 infection was detected in 41.7% of eBL cases versus 24.3% of controls; the odds ratio (OR) was 2.18, and the 95% confidence interval (CI) was 1.12-4.26, which remained significant in adjusted results (adjusted odds ratio [aOR] of 2.40, 95% CI of 1.11-5.17). A total of 29 nucleotide variations and 96 haplotypes were identified, but these were unrelated to eBL. CONCLUSIONS: Our results increase the evidence supporting the hypothesis that infection with mixed Pf infection is increased with eBL and suggest that measuring Pf genetic diversity may provide new insights into the role of Pf infection in eBL.

2.
Int J Cancer ; 146(4): 953-969, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054214

RESUMO

Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in sub-Saharan African countries, however, few epidemiologic studies have been undertaken and none attempted enrolling cases from multiple countries. We therefore conducted a population-based case-control study of eBL in children aged 0-15 years old in six regions in Northern Uganda, Northern Tanzania and Western Kenya, enrolling 862 suspected cases and 2,934 population controls (response rates 98.5-100%), and processing ~40,000 vials of samples using standardized protocols. Risk factor questionnaires were administered, and malaria period prevalence was measured using rapid diagnostic tests (RDTs). A total of 80.9% of the recruited cases were diagnosed as eBL; 61.4% confirmed by histology. Associations with eBL risk were computed using logistic regression models adjusted for relevant confounders. Associations common in at least two countries were emphasized. eBL risk was decreased with higher maternal income and paternal education and elevated with history of inpatient malaria treatment >12 months before enrollment. Reporting malaria-attributed fever up to 6 months before enrollment and malaria-RDT positivity at enrollment were associated with decreased eBL risk. Conversely, reporting exposure to mass malaria suppression programs (e.g., indoor residual insecticide) was associated with elevated risk. HIV seropositivity was associated with elevated eBL risk, but the relative impact was small. The study shows that it is feasible to conduct networked, multisite population-based studies of eBL in Africa. eBL was inversely associated with socioeconomic status, positively associated with inpatient malaria treatment 12 months ago and with living in areas targeted for malaria suppression, which support a role of malaria in eBL.


Assuntos
Linfoma de Burkitt/epidemiologia , Doenças Endêmicas/estatística & dados numéricos , Soropositividade para HIV/epidemiologia , Malária/epidemiologia , Fatores Socioeconômicos , Adolescente , Linfoma de Burkitt/etiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Soropositividade para HIV/complicações , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Malária/complicações , Malária/diagnóstico , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários/estatística & dados numéricos , Tanzânia/epidemiologia , Uganda/epidemiologia
3.
Nat Rev Clin Oncol ; 11(5): 251-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24614139

RESUMO

Cancer research in Africa will have a pivotal role in cancer control planning in this continent. However, environments (such as those in academic or clinical settings) with limited research infrastructure (laboratories, biorespositories, databases) coupled with inadequate funding and other resources have hampered African scientists from carrying out rigorous research. In September 2012, over 100 scientists with expertise in cancer research in Africa met in London to discuss the challenges in performing high-quality research, and to formulate the next steps for building sustainable, comprehensive and multi-disciplinary programmes relevant to Africa. This was the first meeting among five major organizations: the African Organisation for Research and Training in Africa (AORTIC), the Africa Oxford Cancer Foundation (AfrOx), and the National Cancer Institutes (NCI) of Brazil, France and the USA. This article summarizes the discussions and recommendations of this meeting, including the next steps required to create sustainable and impactful research programmes that will enable evidenced-based cancer control approaches and planning at the local, regional and national levels.


Assuntos
Pesquisa Biomédica/organização & administração , Oncologia/organização & administração , África , Participação da Comunidade , Ética em Pesquisa , Fundações/organização & administração , Órgãos Governamentais/organização & administração , Humanos , Agências Internacionais/organização & administração , Cooperação Internacional , Oncologia/educação , National Cancer Institute (U.S.) , Neoplasias/economia , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Neoplasias/terapia , Parcerias Público-Privadas , Sistema de Registros , Apoio à Pesquisa como Assunto , Estados Unidos , Universidades/organização & administração
4.
Ecancermedicalscience ; 8: 396, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24550997

RESUMO

The objectives of the African Organisation for Research and Training in Cancer (AORTIC), both at its inception in the early 1980s, and at its reactivation in 2000 following a decade of inactivity, included bringing the products of decades of advances in cancer research to African populations through international collaboration. The historical perspective provided in this report illustrates progress in achieving these objectives through successive continent-wide activities over a period of 30 years, culminating in the organisation's most recent conference held in Durban, South Africa, 21-24 November 2013. The constant growth in the number of attendants and increasing diversity of the nations of their origin are consistent with advances, whereby the number of participants and the nations of their origin have grown from 24 in 1983 to almost 1000 in 2013, and from 14 to 70, respectively. While earlier AORTIC conferences used to assume the atmosphere of 'jamborees', more recent ones have morphed to problem-solving events, with the concerted collaboration of international organisations, including the World Health Organisation (WHO), International Union Against Cancer (UICC), the Africa Union (AU), the US National Cancer Institute (NCI), the International Psycho-Oncology Society (IPOS), and others. The topics of discussion at the Ninth AORTIC International Conference on Cancer in Africa in Durban were those of paramount importance for low- and middle-income countries: childhood cancers, cancers of the cervix, breast, and prostate, as well as cancer care challenges resulting from ignorance, neglect, and economic deprivation. The role of environmental factors that underlie Burkitt's lymphoma was the subject of the Epidemiology of Burkitt Lymphoma in East-African Children and Minors Workshop, highlighting the NCI research programme in East Africa, while the Workshop on Cost Effectiveness of Treatment of Cancer in Africa surmised that treating childhood cancers is affordable in Africa in spite of widespread economic deprivation. WHO representatives emphasised the organisation's commitment to the global control of non-communicable diseases (NCDs), including cancer, and promoted the new initiatives for the control of cervical cancer, one of the commonest and deadliest cancers in adult Africans. AU representative proffered the principles of 'demographic dividends' for Africa to be able to tackle its burden of NCDs. UICC, represented by its President, provided guidelines for cancer diagnosis and staging, and advised on its effort to improve global access to radiotherapy, especially in Africa, while IPOS led the discussions on mitigating the suffering that is associated with the late presentation of cancer in the region. Oral and poster presentations from various parts of the continent indicate the growth of basic science of cancer in the region, with studies revealing regional diversity in the frequencies of the triple-negative breast cancer. They also suggest a need for genome-wide association studies as well as the evaluation of single nucleotide polymorphisms that may be responsible for variable susceptibility in breast and prostate cancer in people of African descent. Finally, the AORTIC leadership announced its plan for the advancement of cancer control by intensifying cancer advocacy at all levels of governance in the region.

5.
Infect Agent Cancer ; 8(1): 39, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24099039

RESUMO

Infectious Agents and Cancer is introducing a new section of Clinical Oncology with the main objective of stimulating debate through articles published in the section. Infectious diseases have been the major causes of morbidity and mortality in human populations, and have dominated the medical approach to clinical and public health. Successful efforts to control mortality from acute infections have paved the way for chronic, mostly indolent, infections to become major causes of morbidity. Cancer, hitherto thought to be rare in resource-limited settings, is becoming a major contributor. The changes in mortality patterns are due, in part, to diseases linked to rapid changes in lifestyle, urbanization, and pollution. These diseases include many of the non-infection associated cancers. However, there is a dearth of information about the burden, pathogenesis, and therapeutic approaches about cancer in resource-limited countries. There are also substantial other challenges, including economic, infrastructure, technology, and personnel. The Journal advocates for interactive local-global (lo-bal) efforts to generate relevant knowledge about cancer burden, pathogenesis, and therapeutic approaches using a bottom-up approach to sharpen the focus on local and global relevance of research and clinical and public practice, particularly in resource-limited countries. The section on Clinical Oncology in Infectious Agents and Cancer will harness these "lo-bal" strategies to reduce substantially the time from concept, discovery, and development and implementation of locally and globally applicable diagnostic and therapeutic technologies.

6.
J Med Virol ; 85(9): 1602-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23852686

RESUMO

Risk of Kaposi sarcoma (KS) is linked to detection of Kaposi sarcoma-associated herpesvirus (KSHV) DNA in plasma, but little is known about the prevalence and risk factors for plasma KSHV DNA detection among the general population where KS is endemic. Correlates of KSHV plasma detection were investigated in a population-based sample of adult Ugandans (15-59 years) who participated in an HIV/AIDS serobehavioral survey in 2004/2005. KSHV DNA was measured in plasma of 1,080 KSHV seropositive and 356 KSHV seronegative persons using polymerase chain reaction (PCR). KSHV DNA in plasma was detected in 157 (8.7%) persons; of these 149 (95%) were KSHV seropositive and 8 (5%) were seronegative. Detection of KSHV DNA in plasma was significantly associated with male sex (P < 0.001), older age (P = 0.003), residence in a rural versus urban area (P = 0.002), geographic region (P = 0.02), and being KSHV seropositive (13.8% seropositive vs. 2.3% seronegative, P < 0.001). In a multivariable model, KSHV DNA plasma quantity was significantly higher in men (P = 0.002), inversely associated with age (P = 0.05), and residing in an urban area (P = 0.01). In Uganda, KSHV is detected more frequently in the plasma of adult males and residents of rural regions, potentially explaining the increased risk of KS in these subsets of the Ugandan population.


Assuntos
Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/classificação , Herpesvirus Humano 8/isolamento & purificação , Viremia/epidemiologia , Adolescente , Adulto , DNA Viral/sangue , Feminino , Infecções por HIV/complicações , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/genética , Humanos , Masculino , Pessoa de Meia-Idade , Plasma/virologia , Prevalência , Fatores de Risco , Uganda/epidemiologia , Carga Viral , Viremia/virologia , Adulto Jovem
8.
J Acquir Immune Defic Syndr ; 38(4): 474-9, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15764964

RESUMO

BACKGROUND: Human herpesvirus 8 (HHV-8) infection is common in sub-Saharan Africa, but its distribution is uneven. Transmission occurs during childhood within families by unclear routes. METHODS: We evaluated 600 Ugandan children with sickle cell disease and their mothers for factors associated with HHV-8 seropositivity in a cross-sectional study. HHV-8 serostatus was determined using an HHV-8 K8.1 glycoprotein enzyme immunoassay. Odds ratios for seropositivity were estimated using logistic regression, and factor analysis was used to identify clustering among socioeconomic variables. RESULTS: One hundred seventeen (21%) of 561 children and 166 (34%) of 485 mothers with definite HHV-8 serostatus were seropositive. For children, seropositivity was associated with age, mother's HHV-8 serostatus (especially for children aged 6 years or younger), lower maternal education level, mother's income, and low-status father's occupation (P < 0.05 for all). Using communal standpipe or using surface water sources were both associated with seropositivity (OR 2.70, 95% CI 0.80-9.06 and 4.02, 95% CI 1.18-13.7, respectively) as compared to using private tap water. These associations remained, albeit attenuated, after adjusting for maternal education and child's age (P = 0.08). In factor analysis, low scores on environmental and family factors, which captured household and parental characteristics, respectively, were positively associated with seropositivity (P(trend) < 0.05 for both). For mothers, HHV-8 seropositivity was significantly associated with water source and maternal income. CONCLUSIONS: HHV-8 infection in Ugandan children was associated with lower socioeconomic status and using surface water. Households with limited access to water may have less hygienic practices that increase risk for HHV-8 infection.


Assuntos
Infecções por Herpesviridae/epidemiologia , Fatores Socioeconômicos , Abastecimento de Água , Adolescente , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Escolaridade , Pai , Feminino , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/economia , Herpesvirus Humano 8 , Humanos , Renda , Lactente , Razão de Chances , Irmãos , Uganda/epidemiologia , Abastecimento de Água/normas
9.
J Natl Cancer Inst ; 95(17): 1330-5, 2003 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-12953087

RESUMO

BACKGROUND: Although human herpesvirus 8 (HHV-8), the etiologic agent for Kaposi's sarcoma, can be detected in peripheral blood, blood-borne transmission of this virus has not been demonstrated. We studied the association between HHV-8 seropositivity and transfusion history among children with sickle-cell disease in Uganda, where HHV-8 infection is common in blood donors. METHODS: We studied 600 children (aged 0-16 years) with sickle-cell disease at Mulago Hospital, Kampala, from November 2001 through April 2002. By design, about half had previously been transfused. HHV-8 serostatus was determined using enzyme-linked immunosorbent assays for antibodies against HHV-8 proteins K8.1 and orf 73. We used logistic regression to test for an association between HHV-8 serostatus and transfusion history and a Markov model to estimate the transmission risk per transfusion and the cumulative risk from community (i.e., nontransfusion) sources. Statistical tests were two-sided. RESULTS: HHV-8 antibodies were detected in 117 of 561 (21%) children with unambiguous K8.1 results. HHV-8 seroprevalence among the never-transfused children increased with age from 7% in children aged 0-2 years to 32% in those aged 13-16 years (P(trend)<.001). HHV-8 seropositivity was more frequent in transfused than never-transfused children (24% versus 17%, odds ratio = 1.48, 95% confidence interval [CI] = 0.97 to 2.26; P =.07). Seropositivity increased with number of reported transfusions, with age-adjusted odds ratios of 0.97 (95% CI = 0.54 to 1.75), 1.13 (95% CI = 0.59 to 2.17), 1.76 (95% CI = 0.81 to 3.83), and 2.17 (95% CI = 1.18 to 3.99) for children with one, two, three, or four or more transfusions, respectively (P(trend) =.007). Overall, the estimated HHV-8 transmission risk was 2.6% per transfusion (95% CI = 1.9% to 3.3%), whereas the annual risk of infection unrelated to transfusion was 2.7% (95% CI = 1.7% to 3.7%). CONCLUSION: Our study suggests that blood transfusion is associated with a small risk of HHV-8 transmission. In Uganda, this risk is approximately equivalent to the 1-year cumulative risk of infection from community sources.


Assuntos
Anemia Falciforme/terapia , Infecções por Herpesviridae/etiologia , Herpesvirus Humano 8 , Reação Transfusional , Adolescente , Criança , Pré-Escolar , Feminino , Infecções por Herpesviridae/virologia , Humanos , Lactente , Masculino , Cadeias de Markov , Razão de Chances , Estudos Soroepidemiológicos
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