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Chabay P, Lens D, Hassan R, Rodríguez Pinilla SM, Valvert Gamboa F, Rivera I, Huamán Garaicoa F, Ranuncolo SM, Barrionuevo C, Morales Sánchez A, Scholl V, De Matteo E, Preciado MV, Fuentes-Pananá EM. Lymphotropic Viruses EBV, KSHV and HTLV in Latin America: Epidemiology and Associated Malignancies. A Literature-Based Study by the RIAL-CYTED. Cancers (Basel) 2020; 12:E2166. [PMID: 32759793 PMCID: PMC7464376 DOI: 10.3390/cancers12082166] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/11/2020] [Accepted: 07/15/2020] [Indexed: 02/06/2023] Open
Abstract
The Epstein-Barr virus (EBV), Kaposi sarcoma herpesvirus (KSHV) and human T-lymphotropic virus (HTLV-1) are lymphomagenic viruses with region-specific induced morbidity. The RIAL-CYTED aims to increase the knowledge of lymphoma in Latin America (LA), and, as such, we systematically analyzed the literature to better understand our risk for virus-induced lymphoma. We observed that high endemicity regions for certain lymphomas, e.g., Mexico and Peru, have a high incidence of EBV-positive lymphomas of T/NK cell origin. Peru also carries the highest frequency of EBV-positive classical Hodgkin lymphoma (HL) and EBV-positive diffuse large B cell lymphoma, not otherwise specified (NOS), than any other LA country. Adult T cell lymphoma is endemic to the North of Brazil and Chile. While only few cases of KSHV-positive lymphomas were found, in spite of the close correlation of Kaposi sarcoma and the prevalence of pathogenic types of KSHV. Both EBV-associated HL and Burkitt lymphoma mainly affect young children, unlike in developed countries, in which adolescents and young adults are the most affected, correlating with an early EBV seroconversion for LA population despite of lack of infectious mononucleosis symptoms. High endemicity of KSHV and HTLV infection was observed among Amerindian populations, with differences between Amazonian and Andean populations.
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Affiliation(s)
- Paola Chabay
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Daniela Lens
- Flow Cytometry and Molecular Biology Laboratory, Departamento Básico de Medicina, Hospital de Clínicas/Facultad de Medicina, Universidad de la República, CP 11600 Montevideo, Uruguay;
| | - Rocio Hassan
- Oncovirology Laboratory, Bone Marrow Transplantation Center, National Cancer Institute “José Alencar Gomes da Silva” (INCA), Ministry of Health, 20230-130 Rio de Janeiro, Brazil;
| | | | - Fabiola Valvert Gamboa
- Department of Medical Oncology, Cancer Institute and National League against Cancer, 01011 Guatemala City, Guatemala;
| | - Iris Rivera
- Department of Hematology, Salvadoran Institute of Social Security, Medical Surgical and Oncological Hospital (ISSS), 1101 San Salvador, El Salvador;
| | - Fuad Huamán Garaicoa
- Department of Pathology, National Cancer Institute—Society to Fight Cancer (ION-SOLCA), Santiago de Guayaquil Catholic University, Guayaquil 090615, Ecuador;
| | - Stella Maris Ranuncolo
- Cell Biology Department, Institute of Oncology “Angel H. Roffo” School of Medicine, University of Buenos Aires, C1417DTB Buenos Aires, Argentina;
| | - Carlos Barrionuevo
- Department of Pathology, National Institute of Neoplastic Diseases, National University of San Marcos, 15038 Lima, Peru;
| | - Abigail Morales Sánchez
- Research Unit in Virology and Cancer, Children’s Hospital of Mexico Federico Gómez, 06720 Mexico City, Mexico;
| | - Vanesa Scholl
- Department of Integrated Genomic Medicine, Conciencia-Oncohematologic Institute of Patagonia, 8300 Neuquén, Argentina;
| | - Elena De Matteo
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Ma. Victoria Preciado
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Ezequiel M. Fuentes-Pananá
- Research Unit in Virology and Cancer, Children’s Hospital of Mexico Federico Gómez, 06720 Mexico City, Mexico;
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Ishak R, de Oliveira Guimarães Ishak M, Vallinoto ACR. The challenge of describing the epidemiology of HTLV in the Amazon region of Brazil. Retrovirology 2020; 17:4. [PMID: 32059740 PMCID: PMC7023703 DOI: 10.1186/s12977-020-0512-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 02/09/2020] [Indexed: 12/27/2022] Open
Abstract
HTLV-1 was the first described human retrovirus and was soon found to be associated with severe clinical diseases, including a devastating lymphoma/leukemia and other inflammatory diseases. Although HTLV-2 is not usually pathogenic, it is widely distributed among native Indian populations in Brazil, particularly in the Amazon region of the country. Presently, HTLV spreads mainly by the sexual route and from mother to child, and virus persistence is an active biological factor aiding its transmission. Recently, the use of illicit drugs has been shown to be an additional risk factor, showing the influence of new habits on the epidemiology of HTLV in the region. Despite the detection of the virus in several different populations in the Amazon region of Brazil for almost 30 years, the exact prevalence of HTLV-1/2 is not well defined. The original biases in sampling and the selection of epidemiologically unsuitable populations were commonly repeated in most prevalence studies, generating unreliable and conflicting figures that do not represent the actual prevalence of HTLV. The improvements in clinical and laboratory facilities have resulted in the description of several clinical manifestations that were previously unknown in the region. The extent of the spread of the virus must be defined in this region, which is the largest geographical area of the country. As prophylaxis advances toward the use of vaccines against HTLV-1, it is important to determine who is at risk of being infected and developing a disease to successfully implement preventive measures, particularly as proposals are made to eradicate the virus among humans.
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Affiliation(s)
- Ricardo Ishak
- Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Rua Augusto Corrêa no.1, Belém, Pará, 66075-110, Brazil.
| | - Marluísa de Oliveira Guimarães Ishak
- Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Rua Augusto Corrêa no.1, Belém, Pará, 66075-110, Brazil
| | - Antonio Carlos R Vallinoto
- Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Rua Augusto Corrêa no.1, Belém, Pará, 66075-110, Brazil
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Braço ILJ, de Sá KSG, Waqasi M, Queiroz MAF, da Silva ANR, Cayres-Vallinoto IMV, Lima SS, de Oliveira Guimarães Ishak M, Ishak R, Guerreiro JF, Vallinoto ACR. High prevalence of human T-lymphotropic virus 2 (HTLV-2) infection in villages of the Xikrin tribe (Kayapo), Brazilian Amazon region. BMC Infect Dis 2019; 19:459. [PMID: 31117977 PMCID: PMC6532245 DOI: 10.1186/s12879-019-4041-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 04/26/2019] [Indexed: 11/17/2022] Open
Abstract
Background Studies have shown that the human T-lymphotropic virus 2 (HTLV-2) is endemic in several indigenous populations of the Brazilian Amazon and molecular analyses have shown the exclusive presence of HTLV-2 subtype 2c among the indigenous groups of this geographical region. Methods The present study characterizes the prevalence of HTLV-2 infection in three new villages of the Xikrin tribe, in the Kayapo group, according to their distribution by sex and age. The study included 263 samples from individuals from the Kateté, Djujeko and Oodjã villages. Plasma samples were tested for the presence of anti-HTLV-1/2 antibodies using enzyme-linked immunosorbent assays (ELISA). Seropositive samples were confirmed using real-time PCR, nested PCR and sequencing. Results The serological and molecular results confirmed the sole presence of HTLV-2 in 77 (29%) samples, with a prevalence of 38% among women and 18% among men. In these communities, it was found that the prevalence of HTLV-2 infection increased with age. Nucleotide sequences (642 bp, 5’LTR) from eight samples were subjected to phylogenetic analysis by the neighbor-joining method to determine the viral subtype, which confirmed the presence of HTLV-2c. Conclusions The results of the present study establish the presence of HTLV-2 infection in three new villages of the Xikrin tribe and confirm the high endemicity of the infection in the Kayapo indigenous group of the Brazilian Amazon.
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Affiliation(s)
- Isabel Luís Jocene Braço
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Para, Brazil.,Programa de Pós-Graduação em Biologia de Agentes Infecciosos e Parasitários, Universidade Federal do Pará, Belém, Para, Brazil
| | - Keyla Santos Guedes de Sá
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Para, Brazil
| | | | | | | | | | - Sandra Souza Lima
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Para, Brazil
| | | | - Ricardo Ishak
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Para, Brazil
| | - João Farias Guerreiro
- Laboratory of Human and Medical Genetics, Institute of Biological Sciences, Federal University of Pará, Belém, Para, Brazil
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Paiva A, Casseb J. Origin and prevalence of human T-lymphotropic virus type 1 (HTLV-1) and type 2 (HTLV-2) among indigenous populations in the Americas. Rev Inst Med Trop Sao Paulo 2015; 57:1-13. [PMID: 25651320 PMCID: PMC4325517 DOI: 10.1590/s0036-46652015000100001] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 09/02/2014] [Indexed: 01/09/2023] Open
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) is found in indigenous peoples
of the Pacific Islands and the Americas, whereas type 2 (HTLV-2) is widely
distributed among the indigenous peoples of the Americas, where it appears to be more
prevalent than HTLV-1, and in some tribes of Central Africa. HTLV-2 is considered
ancestral in the Americas and is transmitted to the general population and injection
drug users from the indigenous population. In the Americas, HTLV-1 has more than one
origin, being brought by immigrants in the Paleolithic period through the Bering
Strait, through slave trade during the colonial period, and through Japanese
immigration from the early 20th century, whereas HTLV-2 was only brought
by immigrants through the Bering Strait. The endemicity of HTLV-2 among the
indigenous people of Brazil makes the Brazilian Amazon the largest endemic area in
the world for its occurrence. A review of HTLV-1 in all Brazilian tribes supports the
African origin of HTLV-1 in Brazil. The risk of hyperendemicity in these
epidemiologically closed populations and transmission to other populations reinforces
the importance of public health interventions for HTLV control, including the
recognition of the infection among reportable diseases and events.
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Affiliation(s)
- Arthur Paiva
- Universidade Federal de Alagoas, Hospital Universitário, Maceió, Alagoas, Brazil
| | - Jorge Casseb
- Institute of Tropical Medicine of São Paulo, University of São Paulo, São Paulo, SP, Brazil
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Barros Kanzaki LI. Hypothetical HTLV-I induction by ionizing radiation. Med Hypotheses 2006; 67:177-82. [PMID: 16540259 DOI: 10.1016/j.mehy.2006.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 12/20/2005] [Accepted: 01/12/2006] [Indexed: 11/25/2022]
Abstract
Some laboratories have reported HTLV-I genome integration in cancer patients diagnosed with neoplasms of cervix and uterus. Usually, cancer patients undergo radiotherapy besides chemotherapy and surgery. It is hypothesized that radiation exposure would induce HTLV-I genome generation/activation, nevertheless there is not any report on experimental procedures trying to demonstrate HTLV-I gene expression in cells exposed to ionizing radiation. Anyway, earlier experimental works by Lieberman and Kaplan in 1959 succeeded to isolate retroviral particles, the radiation leukemia virus (RadLV), from thymic lymphomas of X-ray-irradiated C57BL/Ka mice, assuming that RadLV activated in the host by ionizing radiation, is released and transported to the thymus, where lymphoblasts, generated during the postradiation recovery phase, constitute an optimal target cell population for both replication of and eventual transformation by virus. Recent studies claim that besides RadLV, another retrovirus (RadLV-0) also induced by ionizing radiation is expressed and would be responsible for transformed cells of bone marrow origin. Epidemiological studies coincidentally point out to high incidence of HTLV-I infection in geographic areas displaying significant levels of radioactivity contamination as in Central Africa, Japan Islands and Mururoa Atoll. In our research work, we detected HTLV-I antibodies and viral genome integration in cancer patients of cervix and uterus and health care workers, whose had been exposed to ionizing radiation during radiotherapeutic procedures. Recombinational events among endogenous retrovirus and other retrogenic elements in the host cell genome under the bombardment of ionizing radiation from different sources could have optimized the phenomena occurrence or even ignited them to happen, generating HTLV-I genome, related viral peptides and virions. Therefore, it is feasible that exposure to ionizing radiation during therapeutic procedures could generate HTLV-I genome or induce the virus to be expressed in cells of cancer patients submitted to radiotherapy as also in healthy subjects under the same conditions, in artificial or natural radiation environment.
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Affiliation(s)
- Luis Isamu Barros Kanzaki
- PIADICUFAP, Federal University of Amapa, Rodovia Juscelino Kubtscheck de Oliveira, Km 02, CEP 68 902 280, Macapá, Amapá, Brazil.
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Hurtado AM, Lambourne CA, James P, Hill K, Cheman K, Baca K. HUMAN RIGHTS, BIOMEDICAL SCIENCE, AND INFECTIOUS DISEASES AMONG SOUTH AMERICAN INDIGENOUS GROUPS. ANNUAL REVIEW OF ANTHROPOLOGY 2005. [DOI: 10.1146/annurev.anthro.32.061002.093406] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Despite the efforts of international health agencies to reduce global health inequalities, indigenous populations around the world remain largely unaffected by such initiatives. This chapter reviews the biomedical literature indexed by the PubMed database published between 1963 and 2003 on South American indigenous populations, a total of 1864 studies that include 63,563 study participants. Some language family groupings are better represented than are others, and lowland groups are better represented than are highland groups. Very few studies focus on major health threats (e.g., tuberculosis, influenza), public health interventions, or mestizo-indigenous epidemiological comparisons. The prevalence rates of three frequently studied infections—parasitism, human T-cell lymphotropic viral infection (HTLV), and hepatitis—are extraordinarily high, but these facts have been overlooked by national and international health agencies. This review underscores the urgent need for interventions based on known disease prevalence rates to reduce the burden of infectious diseases in indigenous communities.
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Affiliation(s)
- A. Magdalena Hurtado
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico 87131;, , , ,
| | - Carol A. Lambourne
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico 87131;, , , ,
| | - Paul James
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico 87131;, , , ,
| | - Kim Hill
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico 87131;, , , ,
| | - Karen Cheman
- Mel & Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona 85724
| | - Keely Baca
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico 87131;, , , ,
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Almeida Cunha RP, Alves FP, Rocha AMC, Rocha GA, Camargo LMA, Nogueira POP, Camargo EP, Queiroz DMM. Prevalence and risk factors associated with Helicobacter pylori infection in native populations from Brazilian Western Amazon. Trans R Soc Trop Med Hyg 2003; 97:382-6. [PMID: 15259462 DOI: 10.1016/s0035-9203(03)90063-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We evaluated the prevalence of, and factors associated with, Helicobacter pylori infection in 222 subjects from 3 distinct communities of native populations (Uru-Eu-Wau-Wau Indians and 2 riverine communities living on the banks of the Machado river and in Portuchuelo) living in isolation in the rainforest of Brazilian Western Amazon. The overall prevalence was 78.8% (95% CI 72.7-83.9). The prevalence was higher in the Machado river community compared with Portuchuelo (chi2 = 3.84, P = 0.05), but no significant difference was observed between the Machado river community and the Uru-Eu-Wau-Wau Indians. Logistic regression showed that residential crowding and age were factors associated with the presence of H. pylori infection. Acquisition of the bacterium started early in life and by the age of 2 years 50% of children were infected. The prevalence increased with age, reaching near universal levels during adulthood (97.9%). Residential crowding was high with a global index of 3.3 persons/room (SD = 1.8), varying significantly between the 3 communities (P = 0.001). These data provide further evidence supporting direct person-to-person spread of the bacterium.
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Affiliation(s)
- R P Almeida Cunha
- Center for Research in Tropical Medicine, Br 364, km 3,5 Porto Velho, Rondônia, CEP 78900-000, Brazil
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Human T cell lymphotropic viruses (HTLV-I/II) in South America: Should it be a public health concern? J Biomed Sci 2002. [DOI: 10.1007/bf02254986] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Farias de Carvalho SM, Pombo de Oliveira MS, Thuler LC, Rios M, Coelho RC, Rubim LC, Silva EM, Reis AM, Catovsky D. HTLV-I and HTLV-II infections in hematologic disorder patients, cancer patients, and healthy individuals from Rio de Janeiro, Brazil. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1997; 15:238-42. [PMID: 9257659 DOI: 10.1097/00042560-199707010-00008] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To clarify the seroprevalence of human T-cell lymphotropic virus type I (HTLV-I) among hematologic and cancer patients in the State of Rio de Janeiro, Brazil, we investigated sera from 2430 individuals from the following groups: 152 patients with T-cell diseases, 250 with B-cell disorders, 67 with myeloid leukemia, 41 with Hodgkin's disease, 351 with a history of multiple blood transfusions, 235 patients with solid tumors of different types, and 109 family members of HTLV-I-infected patients. Antibodies to HTLV-I were screened by enzyme-linked immunosorbent assay or particle agglutination assays (or both). Repeatedly reactive samples were tested by Western blot and polymerase chain reaction assay to differentiate HTLV-I from HTLV-II. We found an increased seroprevalence rate of HTLV-I among those with lymphoid malignancies, mainly in T-cell diseases (28.9%), and these results were important in characterizing 44 cases of adult T-cell leukemia/lymphoma. We confirmed the presence of HTLV-I and HTLV-II infections in blood donors (0.4% and 0.1%, respectively), in patients exposed to multiple blood transfusions (10.2% and 0.8%, respectively), and in 30 (27.5%) of 109 family members of HTLV-I- or HTLV-II-infected patients. We also confirmed the high rate occurrence of adult T-cell leukemia/lymphoma among lymphoproliferative disorders in Rio de Janeiro, Brazil.
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Linhares MI, Malagueño E, Carvalho LB, de Oliveira VF, Minamishima Y. No relationship between HTLV-1 infection and filariasis--Serological study on patients with filariasis in Recife, Brazil. Microbiol Immunol 1995; 39:917-9. [PMID: 8657021 DOI: 10.1111/j.1348-0421.1995.tb03278.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The seroprevalence of antibodies against human T-cell leukemia virus was determined by ELISA in 68 patients with filarial infestation living in an endemic area. The total seropositivity was 2.9% and the HTLV-1-positive cases were detected in 2 microfilaremic patients 12 and 40 years old. This value is very close to that obtained for healthy individuals in the same region and age groups. This result suggests that there is no relationship between filariasis and HTLV-1 infection as previously proposed.
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Affiliation(s)
- M I Linhares
- Laboratório de Imunopatologia Keizo Asami, Universidade Federal de Pernambuco, Recife, Brazil
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Black FL, Biggar RJ, Neel JV, Maloney EM, Waters DJ. Endemic transmission of HTLV type II among Kayapo Indians of Brazil. AIDS Res Hum Retroviruses 1994; 10:1165-71. [PMID: 7826700 DOI: 10.1089/aid.1994.10.1165] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Serological studies on 926 blood samples from 703 Brazilian Kayapo (Cayapo) Indians showed, by conventional definition of HTLV seropositivity, a 28% prevalence of human T lymphotropic virus (HTLV) infection, the highest yet reported. Immunoblot (WB) and SYNTH-EIA patterns indicate that the predominant infecting agent is type II. Of children under 15 years old, 12% were positive, and of persons over 60, more than 60%. Perinatal and heterosexual modes of transmission offer an adequate explanation of this incidence. Infection in infancy may include infection via breast milk from women other than the mother. Evidence of new infection in adults is apparent at an earlier age in women than in men. This pattern of antibody prevalence was not determined by cohort effects, as demonstrated by tests of serial specimens. Enzyme immunosorbent assay (EIA) absorbencies were not stable in the paired specimens: five serum pairs reverted and mean absorbencies declined over some age ranges. Many specimens with relatively high, but less than positive, EIA results were positive by immunoblot (WB). This suggests that the standard EIA end point does not identify all infected persons. If the WB alone indicates positivity, 47% of the whole population, and more than 80% of the older age groups, are infected with HTLV-II.
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Affiliation(s)
- F L Black
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut 06520-8034
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