| 1. |
- Bjerregaard-Andersen, Morten, et al.
(författare)
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Tuberculosis burden in an urban population: a cross sectional tuberculosis survey from Guinea Bissau
- 2010
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Ingår i: BMC Infectious Diseases. - : Springer Science and Business Media LLC. - 1471-2334. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Little is known about the prevalence of pulmonary tuberculosis (TB) in low income countries. We conducted a cross sectional survey for pulmonary TB and TB symptoms in Bissau, Guinea-Bissau, in an urban cohort with known HIV prevalence. TB surveillance in the area is routinely based on passive case finding. Methods: Two cohorts were selected based on a previous HIV survey, but only 52.5% of those enrolled in the adult cohort had participated in the HIV survey. One cohort included all adults living in 384 randomly selected houses; in this cohort 8% (135/1687) were HIV infected. The other included individuals 50 years or older from all other houses in the study area; of these 11% (62/571) were HIV infected. Symptom screening was done through household visits using a standardised questionnaire. TB suspects were investigated with sputum smear microscopy and X-ray. Results: In the adult cohort, we found 4 cases among 2989 individuals screened, giving a total TB prevalence of 134/100,000 (95% CI 36-342/100,000). In the >50 years cohort, we found 4 cases among 571 individuals screened, giving a total prevalence of 701/100,000 (191-1784/100.000). Two of the eight detected TB cases were unknown by the TB program. Of the total TB cases five were HIV uninfected while three had unknown HIV status. The prevalence of TB symptoms was 2.1% (63/2989) and 10.3% (59/571) in the two cohorts respectively. Conclusions: In conclusion we found a moderately high prevalence of pulmonary TB and TB symptoms in the general population, higher among elderly individuals. By active case finding unknown cases were detected. Better awareness of TB and its symptoms needs to be promoted in low income settings.
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| 2. |
- da Silva, Zacarias, et al.
(författare)
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Decline in human T-cell lymphotropic virus-1 prevalence in urban areas of Bissau, Guinea-Bissau: exploring the association with HIV infections.
- 2009
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Ingår i: AIDS. - 1473-5571. ; 23, s. 637-639
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Tidskriftsartikel (refereegranskat)abstract
- In 2006, a cross-sectional survey of 384 randomly selected houses within a community-based follow-up study was conducted to assess the human T-cell lymphotropic virus (HTLV) prevalence in Bissau. Changes in prevalence and incidence rates were assessed based on a similar survey carried out 10 years earlier. The prevalence of HTLV-1 declined significantly from 3.5% in 1996 to 2.3% in 2006. The incidence between 1996 and 2006 was only 0.9/1000 person-years and tended to be higher for women than for men.
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| 3. |
- da Silva, Zacarias J., et al.
(författare)
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Changes in prevalence and incidence of HIV-1, HIV-2 and dual infections in urban areas of Bissau, Guinea-Bissau : is HIV-2 disappearing?
- 2008
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Ingår i: AIDS. - London : Gower Academic Journals. - 0269-9370 .- 1473-5571. ; 22:10, s. 1195-1202
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Objectives: To assess the changes in HIV prevalence and incidence between 1996 and 2006 in urban areas of Bissau.Design: A cross-sectional survey of 384 randomly selected houses within a community-based follow-up study of HIV-1 and HIV-2.Methods: A total of 3242 individuals aged at least 15 years were eligible for inclusion. Participants were interviewed about behavioral and socio-economic factors and had a blood sample drawn. A total of 2548 individuals were tested for antibodies to HIV-1 and HIV-2, of whom 649 had taken part in a similar survey in 1996.Results: With 0.5% HIV dual reactions included, the overall HIV-1 prevalence was 4.6% (118 out of 2548) and the HIV-2 prevalence was 4.4% (112 out of 2548). The prevalence of HIV-1 increased more for women than men especially in the 25-34-year age group. HIV-2 prevalence decreased below 45 years of age but not for individuals more than 45 years old. The incidence rate between 1996 and 2006 was 0.5 per 100 person-years for HIV-1 and 0.24 per 100 person-years for HIV-2. Compared with a previous period from 1987 to 1996, the incidence of HIV-2 is declining whereas no significant increase in the incidence of HIV-1 was observed.Conclusions: The present study shows an increasing prevalence of HIV-1 and a decreasing prevalence of HIV-2 in Guinea-Bissau. HIV is generally a bigger problem for women. Despite the general decline in prevalence, HIV-2 may continue as an infection in older people, especially women.
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| 4. |
- Norrgren, Hans, et al.
(författare)
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Increased prevalence of HTLV-1 in patients with pulmonary tuberculosis coinfected with HIV, but not in HIV-negative patients with tuberculosis
- 2008
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Ingår i: Journal of Acquired Immune Deficiency Syndromes. - Philadelphia, PA : Lippincott Williams & Wilkins. - 1525-4135 .- 1944-7884. ; 48:5, s. 607-610
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Tidskriftsartikel (refereegranskat)abstract
- Background: Few and inconclusive results have been presented regarding the influence of human T-lymphotropic virus 1 (HTLV-1) infection on the risk of acquiring tuberculosis (TB). Methods: In 1994-1997, we performed a prospective study on hospitalized adult patients with pulmonary TB in Guinea-Bissau and compared the clinical outcome in HIV-2 and HIV-negative patients. We determined the prevalence of HTLV-1 in all patients screened and diagnosed with TB in that study and compared the infection rate with a serosurvey of HTLV-1 in a population sample from a community-based study conducted at the same time and in the same city. Results: In the TB group, a total of 32 (11.4%) of 280 patients were positive for HTLV-1. This was significantly higher compared with the population-based group in which 74 (3.5%) of 2117 were HTLV-1 positive [crude odds ratio (OR) = 3.6; 95% confidence interval (CI) 2.2 to 5.6, P < 0.001]. However, in a logistic regression analysis controlling for age, gender, and HIV result, the difference was no longer significant (OR = 1.61; 95% CI 0.95 to 2.70, P = 0.074). In HIV-negative patients, no association was found between HTLV-1 and TB (OR = 1.18; 95% CI 0.48 to 2.89, P = 0.71), whereas a significant association was found in HIV-positive patients (OR = 2.41; 95% CI 1.26 to 4.61, P = 0.008). Conclusions: The immunosuppressive effect of HTLV-1 alone was not enough to increase the risk of TB in a highly endemic country, but HTLV-1 increased the risk of TB among HIV-infected individuals.
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| 5. |
- Nowroozalizadeh, Salma, et al.
(författare)
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Microbial Translocation Correlates with the Severity of Both HIV-1 and HIV-2 Infections
- 2010
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Ingår i: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 201:8, s. 1150-1154
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Tidskriftsartikel (refereegranskat)abstract
- Microbial translocation has been linked to systemic immune activation during human immunodeficiency virus (HIV) type 1 infection. Here, we show that an elevated level of microbial translocation, measured as plasma lipopolysaccharide (LPS) concentration, correlates with AIDS in both individuals infected with HIV type 1 and individuals infected with HIV type 2. LPS concentration also correlates with CD4(+) T cell count and viral load independently of HIV type. Furthermore, elevated plasma LPS concentration was found to be concomitant with defective innate and mitogen responsiveness. We suggest that microbial translocation may contribute to loss of CD4(+) T cells, increase in viral load, and defective immune stimuli responsiveness during both HIV type 1 and HIV type 2 infections.
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| 6. |
- Nowroozalizadeh, Salma, et al.
(författare)
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Studies on toll-like receptor stimuli responsiveness in HIV-1 and HIV-2 infections
- 2009
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Ingår i: Cytokine. - : Elsevier BV. - 1096-0023 .- 1043-4666. ; 46:3, s. 325-331
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Tidskriftsartikel (refereegranskat)abstract
- Background: HIV-1 and HIV-2 are two related viruses with distinct clinical outcomes, where HIV-1 is more pathogenic and transmissible than HIV-2. The pathogenesis of both infections is influenced by the dysregulation and deterioration of the adaptive immune system. However, their effects on the responsiveness of innate immunity are less well known. Here, we report on toll-like receptor (TLR) stimuli responsiveness in HIV-1 or HIV-2 infections. Methods: Whole blood from 235 individuals living in Guinea-Bissau who were uninfected, infected with HIV-1, infected with HIV-2, and/or infected with HTLV-1, was stimulated with TLR7/8 and TLR9 agonists, R-848 and unmethylated CpG DNA. After TLR7/8 and TLR9 stimuli, the expression levels of IL-12 and IFN-alpha were related to gender, age, infection status, CD4(+) T cell counts. and plasma viral load. Results: Defective TLR9 responsiveness was observed in the advanced disease stage, along with CD4(+) T cell loss in both HIV-1 and HIV-2 infections. Moreover, TLR7/8 responsiveness was reduced in HIV-1 infected individuals compared with uninfected controls. Conclusions: Innate immunity responsiveness can be monitored by whole blood stimulation. Both advanced HIVA and HIV-2 infections may cause innate immunity dysregulation. (C) 2009 Elsevier Ltd. All rights reserved.
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| 7. |
- Rieckmann, Andreas, et al.
(författare)
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The Effect of Smallpox and Bacillus Calmette-Guérin Vaccination on the Risk of Human Immunodeficiency Virus-1 Infection in Guinea-Bissau and Denmark
- 2017
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Ingår i: Open Forum Infectious Diseases. - 2328-8957. ; 4:3
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Tidskriftsartikel (refereegranskat)abstract
- Background. The live smallpox and Bacillus Calmette-Guérin (BCG) vaccinations have been associated with better adult survival in both Guinea-Bissau and Denmark. In Guinea-Bissau, human immunodeficiency virus (HIV)-1 became an important cause of death after smallpox vaccination was phased out globally in 1980. We hypothesised that smallpox and BCG vaccinations were associated with a lower prevalence of HIV-1 infection, and we tested this hypothesis in both Guinea-Bissau and Denmark. Methods. We conducted 2 studies: (1) a cross-sectional study of HIV infection and vaccination scars in Guinea-Bissau including 1751 individuals and (2) a case-base study with a background population of 46 239 individuals in Denmark. In Guinea-Bissau, HIV-1 transmission was almost exclusively sexually transmitted. In Denmark, we excluded intravenous drug users. Data were analyzed using logistic regression. Results. Bacillus Calmette-Guérin and/or smallpox vaccination compared with neither of these vaccines was associated with an adjusted odds ratio (aOR) for HIV-1 of 0.62 (95% confidence interval [CI], 0.36-1.07) in Guinea-Bissau and 0.70 (95% CI, 0.43-1.15) in Denmark. We combined the results from both settings in a meta-analysis (aOR = 0.66; 95% CI, 0.46-0.96). Data from Guinea-Bissau indicated a stronger effect of multiple smallpox vaccination scars (aOR = 0.27; 95% CI, 0.10-0.75) as follows: women, aOR = 0.18 (95% CI, 0.05-0.64); men, aOR = 0.52 (95% CI, 0.12-2.33); sex-differential effect, P = .29. Conclusions. The studies from Guinea-Bissau and Denmark, 2 very different settings, both suggest that the BCG and smallpox vaccines could be associated with a decreased risk of sexually transmitted HIV-1. It might be informative to pursue this observation and explore possible protective mechanisms as part of the search for an HIV-1 vaccine.
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| 8. |
- Vinner, Lasse, et al.
(författare)
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Sequence analysis of HIV-1 isolates from Guinea-Bissau: selection of vaccine epitopes relevant in both West African and European countries.
- 2011
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Ingår i: APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. - : Wiley. - 1600-0463. ; 119:8, s. 487-497
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Tidskriftsartikel (refereegranskat)abstract
- For a CD8 epitope-based vaccine to match different geographic locations, the targeted epitopes for cytotoxic T-lymphocytes (CTLs) must be present in the local circulating HIV-1 strains. Secondly, the vaccine epitopes should match the host population HLA types. We characterized two new HIV-1 isolates from Guinea-Bissau. Also, we have identified 15 subdominant CD8 epitopes representing common HLA super-types theoretically covering most HLA alleles in any population. Herein we demonstrate that the selected vaccine epitopes are well conserved and simultaneously present in sequences from West Africa and Denmark. Use of the selected epitopes will likely ensure 10 immune targets in the majority of candidates for experimental therapeutic vaccination in both geographic regions. Our results warrant testing of the selected vaccine epitopes in both geographic locations.
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| 9. |
- Özkaya Sahin, Gülsen, et al.
(författare)
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Effect of Complement on HIV-2 Plasma Antiviral Activity Is Intratype Specific and Potent
- 2013
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Ingår i: Journal of Virology. - 1098-5514. ; 87:1, s. 273-281
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Tidskriftsartikel (refereegranskat)abstract
- Human immunodeficiency virus type-2 (HIV-2) infected individuals develop immunodeficiency with a considerable delay and transmit the virus at a lower rate as compared to HIV-1 infected. Conceivably, comparative studies on immune responsiveness of the HIV-1 and HIV-2 infected hosts may help to explain differences in pathogenesis and transmission between the two types of infection. Previous studies have shown that the neutralizing antibody response is more potent and broader in HIV-2 than HIV-1 infection. In the present study we have further examined the function of the humoral immune response and studied the potentiating effect of complement (C') on antiviral activity of plasma from singly HIV-1 or HIV-2 infected, as well as HIV-1/HIV-2 dually infected individuals. Neutralization and antibody-dependent complement-mediated inactivation of HIV-1 and HIV-2 isolates were tested in a plaque reduction assay using U87.CD4-CCR5 cells. Results showed that addition of C' increased intra-type antiviral activity of both HIV-1 and HIV-2 plasma, although the C' effect was more pronounced with HIV-2 than HIV-1 plasma. Using the area-under-curve (AUC)-based readout, multivariate statistical analysis confirmed that type of HIV infection was independently associated with the magnitude of the C' effect. Analysis carried out with purified IgG indicated that the C' effect was largely exerted through the classical C' pathway involving IgG in both HIV-1 and HIV-2 infections. In summary, these findings suggest that antibody binding to HIV-2 structures facilitates efficient use of C', and may thereby be one factor contributing to a strong antiviral activity present in HIV-2 infection.
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| 10. |
- Özkaya Sahin, Gülsen, et al.
(författare)
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Potent Intratype Neutralizing Activity Distinguishes Human Immunodeficiency Virus Type 2 (HIV-2) from HIV-1
- 2012
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Ingår i: Journal of Virology. - 1098-5514. ; 86:2, s. 961-971
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Tidskriftsartikel (refereegranskat)abstract
- HIV-2 has a lower pathogenicity and transmission rate than HIV-1. Neutralizing antibodies could be contributing to these observations. Here we explored side by side potency and breadth of intratype and intertype neutralizing activity (NAc) in plasma of 20 HIV-1, 20 HIV-2 and 11 dually HIV-1/2 (HIV-D) seropositive individuals from Guinea-Bissau, West Africa. Panels of primary isolates, five HIV-1 and five HIV-2, were tested in a plaque reduction assay using U87.CD4-CCR5 cells as targets. Intratype NAc in HIV-2 plasma was found to be considerably more potent, and also broader, than intratype NAc in HIV-1 plasma. This indicates that HIV-2 infected individuals display potent type-specific neutralizing antibodies, whereas such a strong type-specific antibodies are absent in HIV-1 infection. Furthermore, potency of intratype NAc was positively associated with viral load of HIV-1, but not HIV-2, suggesting that NAc in HIV-1 infection is more antigen stimulation-dependent than in HIV-2 infection where plasma viral loads typically are at least tenfold lower than in HIV-1 infection. Intertype NAc of both HIV-1 and HIV-2 infected was instead of low potency. HIV-D subjects had NAc to HIV-2 with similar high potency as singly HIV-2 infected individuals, whereas neutralization of HIV-1 remained poor, indicating that the difference in NAc between HIV-1 and HIV-2 infections depends on the virus itself. We suggest that immunogenicity and/or antigenicity, meaning the neutralization phenotype, of HIV-2 is distinct from HIV-1, and that HIV-2 may display structures that favour triggering of potent neutralizing antibody responses.
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