| 1. |
- 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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| 2. |
- 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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| 3. |
- 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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| 4. |
- 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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