| 1. |
- Biague, Antonio Jaime, et al.
(författare)
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High sexual risk taking and diverging trends of HIV-1 and HIV-2 in the military of Guinea Bissau
- 2011
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Ingår i: Journal of Infection in Developing Countries. ; 5:4, s. 301-308
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: HIV and other sexually transmitted infections are a growing problem in the military personnel of Africa, and information about this problem in Guinea-Bissau is lacking. The aims of this study were to determine the prevalence and trends of the HIV epidemics in the military forces of Guinea Bissau and to explore possible risk factors for HIV infection. METHODOLOGY: Repeated cross-sectional surveys of HIV-1 and HIV-2 were conducted between 1992 and 2005, and knowledge, sexual behaviour and risk factors for HIV-1 and HIV-2 in military personnel in Guinea-Bissau were assessed. RESULTS: The seroprevalence of HIV-1, HIV-2 and HIV-1+HIV-2 dual reactivity was 1.1%, 8.4% and 0.1% in 1992-95, and in 2005 7.7%, 5.1% and 1.9%, respectively. Both the increase of HIV-1 and the decline of HIV-2 between 1992-95 and 2005 were significant when adjusted for age (p < 0.001 for both changes). Only a minority did not know how HIV transmits, but sexual risk taking was high. Several significant risk factors were found in univariate analyses for HIV-1 and HIV-2, but the only risk factor that remained significant after multivariate regression analysis was previous contact with a prostitute among HIV-1-positive subjects (single and dually reactive) (p < 0.01). CONCLUSION: The increasing trend of HIV-1 and the high risky sexual behavior illustrate the need for improvement in HIV/AIDS prevention efforts among military personnel in Guinea Bissau.
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| 2. |
- Borggren, Marie, et al.
(författare)
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Neutralizing Antibody Response and Antibody-Dependent Cellular Cytotoxicity in HIV-1-Infected Individuals from Guinea-Bissau and Denmark
- 2016
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Ingår i: AIDS Research and Human Retroviruses. - : Mary Ann Liebert Inc. - 0889-2229 .- 1931-8405. ; 32:5, s. 434-442
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Tidskriftsartikel (refereegranskat)abstract
- The development of therapeutic and prophylactic HIV vaccines for African countries is urgently needed, but the question of what immunogens to use needs to be answered. One approach is to include HIV envelope immunogens derived from HIV-positive individuals from a geographically concentrated epidemic with more limited viral genetic diversity for a region-based vaccine. To address if there is a basis for a regional selected antibody vaccine, we have screened two regionally separate cohorts from Guinea-Bissau and Denmark for neutralizing antibody activity and antibody-dependent cellular cytotoxicity (ADCC) against local and nonlocal circulating HIV-1 strains. The neutralizing activity did not demonstrate higher potential against local circulating strains according to geography and subtype determination, but the plasma from Danish individuals demonstrated significantly higher inhibitory activity than that from Guinea-Bissau individuals against both local and nonlocal virus strains. Interestingly, an opposite pattern was observed with ADCC activity, where Guinea-Bissau individual plasma demonstrated higher activity than Danish plasma and was specifically against the local circulating subtype. Thus, on basis of samples from these two cohorts, no local-specific neutralizing activity was detected, but a local ADCC response was identified in the Guinea-Bissau samples, suggesting potential use of regional immunogens for an ADCC-inducing vaccine.
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| 3. |
- Lindman, Jacob, et al.
(författare)
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Performance of Bio-Rad HIV-1/2 Confirmatory Assay in HIV-1, HIV-2 and HIV-1/2 dually reactive patients - comparison with INNO-LIA and immunocomb discriminatory assays
- 2019
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Ingår i: Journal of Virological Methods. - : Elsevier BV. - 0166-0934. ; 268, s. 42-47
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Tidskriftsartikel (refereegranskat)abstract
- Background: Being able to discriminate between HIV-1, HIV-2 and HIV-1/2 dual infection is imperative for the appropriate selection of antiretroviral therapy (ART) in regions with high HIV-2 endemicity. Objectives: To evaluate Bio-Rad Geenius HIV-1/2 Confirmatory Assay against INNO-LIA HIV 1/2 Score and ImmunoComb HIV 1/2 BiSpot with an emphasis towards ability to discriminate between HIV-1, HIV-2 and HIV-1/2 dual infection. Material and Methods: 131 samples from ART naïve HIV infected patients in Guinea-Bissau were selected retrospectively and tested with Geenius, INNO-LIA and Immunocomb. HIV-1/2 RNA were measured in all samples and HIV-1/2 DNA in 59 samples. Results: The Geenius reader typed 62 samples as HIV-1 reactive, 37 samples as HIV-2 reactive and 32 samples as HIV-1/2 dually reactive. Geenius manual reading classified 10% more samples as HIV-1/2 dually reactive (n = 35). INNO-LIA typed 63 samples as HIV-1 reactive, 36 samples as HIV-2 reactive and 32 samples as HIV-1/2 dually reactive while Immunocomb classified a large proportion of samples as HIV-1/2 dually reactive (n = 45). The measurement of agreement of the Geenius reader compared with INNO-LIA and Immunocomb was 92.4% and 84.0% respectively while the measurement of agreement of Geenius manual reading compared with INNO-LIA and Immuncomb was 93.1% and 89.3% respectively. Conclusions: Geenius has similar performance characteristics as INNO-LIA, and performs considerably better than Immunocomb, for differentiating between HIV types. This is especially true when using the Geenius reader while manual reading of the Geenius assay seemed to overestimate the numbers of HIV-1/2 dually reactive samples.
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| 4. |
- Lopatko Lindman, Jacob, et al.
(författare)
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Declining prevalence rates of syphilis among police officers in Guinea-bissau, west Africa, 1990-2010.
- 2013
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Ingår i: Sexually Transmitted Diseases. - 1537-4521. ; 40:10, s. 794-796
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Tidskriftsartikel (refereegranskat)abstract
- We analyzed prevalence rates of syphilis (positive Treponema pallidum hemagglutinin antigen/T. pallidum particle antigen and venereal disease research laboratory test) among police officers in Guinea-Bissau from 1990 to 2010 and found a significant decline from 4.5% to 0.4% (P = 0.0065). Our results are in line with other recent reports from West Africa. More research is needed to identify the reasons for this decline.
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| 5. |
- Månsson, Fredrik, et al.
(författare)
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Trends of HIV-1 and HIV-2 prevalence among pregnant women in Guinea-Bissau, West Africa: possible effect of the civil war 1998-1999.
- 2007
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Ingår i: Sexually Transmitted Infections. - : BMJ. - 1368-4973. ; 83:6, s. 463-467
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Sentinel surveys in Bissau, the capital of Guinea-Bissau, have shown low prevalence of HIV-1 but high HIV-2 prevalence before 1998. Guinea-Bissau experienced a civil war in 1998-1999. To examine specifically the trends of HIV prevalence from antenatal surveys in Bissau, Guinea-Bissau in 1987-2004, and whether the civil war in 1998-1999 could have an effect on HIV prevalence levels after the conflict. Methods: Since 1987, anonymous HIV testing in delivering women has been performed at the maternity clinic, Simao Mendes National Hospital, Bissau, as part of the national sentinel surveillance programme. Consecutive sampling was performed for approximately 3 months between September and December each year. Serological analyses were performed at the National Public Health Laboratory in Guinea-Bissau. Results: A total of 20 422 women were tested for HIV between 1987 and 2004. The total HIV-1 prevalence increased from 0.0% in 1987 to 4.8% in 2004 and the total HIV-2 prevalence decreased from 8.3% in 1987 to 2.5% in 2004. The HIV-1 prevalence increased from 2.5% in 1997 to 5.2% in 1999, but stabilized in subsequent years. Conclusions: There was a significant increase in HIV-1 prevalence in the years 1987-2004 and a significant decline in HIV-2 prevalence over the same period. The civil war in 1998-1999 may have sparked HIV-1 transmission, as HIV-1 prevalence more than doubled between 1997 and 1999, but there is no evidence of a long-term effect on the trends of HIV-1 or HIV-2 prevalence.
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| 6. |
- Palm, Angelica A., et al.
(författare)
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Low Postseroconversion CD4+ T-cell Level Is Associated with Faster Disease Progression and Higher Viral Evolutionary Rate in HIV-2 Infection
- 2019
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Ingår i: mBio. - 2161-2129. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- A positive correlation between virus evolutionary rate and disease progression has been shown for human immunodeficiency virus type 1 (HIV-1) infection. Much less is known about HIV-2, the second causative agent of AIDS. We analyzed 528 HIV-2 env V1-C3 sequences generated from longitudinal plasma samples that were collected from 16 study participants during a median observation time of 7.9 years (interquartile range [IQR], 5.2 to 14.0 years). Study participants were classified as faster or slower disease progressors based on longitudinal CD4+ T-cell data. The HIV-2 evolutionary rate was significantly associated with CD4+ T-cell levels and was almost twice as high among the faster progressors as among the slower progressors. Higher evolutionary rates were accounted for by both synonymous and nonsynonymous nucleotide substitutions. Moreover, slow disease progression was associated with stronger positive selection on HIV-2/SIVsm (simian immunodeficiency virus infecting sooty mangabey) surface-exposed conserved residues. This study demonstrated a number of previously unknown characteristics linking HIV-2 disease progression with virus evolution. Some of these findings distinguish HIV-2 from HIV-1 and may contribute to the understanding of differences in pathogenesis.IMPORTANCE The relationship between HIV evolution and disease progression is fundamental to our understanding of HIV immune control and vaccine design. There are no clear definitions for faster and slower HIV-2 disease progression and for the relationship of the rate of progression with HIV-2 evolution. To address the hypothesis that viral evolution is correlated with disease progression in HIV-2 infection, we determined faster and slower disease progression based on follow-up data from a prospective cohort of police officers in Guinea-Bissau. The analysis showed that although the CD4+ T-cell level and the decline in the level were independently associated with progression to AIDS, only the CD4+ T-cell level or a combined CD4+ T-cell level/decline stratification was associated with the rate of HIV-2 evolution. The HIV-2 evolutionary rate was almost twice as high among the faster progressors as among the slower progressors. Importantly, this report defines previously unknown characteristics linking HIV-2 disease progression with virus evolution.
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| 7. |
- Palm, Angelica, et al.
(författare)
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Co-circulation of several similar but unique HIV-1 recombinant forms in Guinea-Bissau revealed by near full-length genomic sequencing.
- 2015
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Ingår i: AIDS Research and Human Retroviruses. - 1931-8405. ; 31:9, s. 938-945
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Tidskriftsartikel (refereegranskat)abstract
- The dynamic HIV-1 epidemic has resulted in the emergence of several different subtypes and recombinant forms that may differ in biological properties. A recombinant form of CRF02_AG and sub-subtype A3 (A3/02) was recently described based on env sequencing and associated with faster disease progression rates compared with its parental strains. Here, we performed near full-length sequencing of the A3/02 variant to characterize the recombination patterns of a potential novel and more pathogenic circulating recombinant form of HIV-1 in Guinea-Bissau.
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| 8. |
- Palm, Angelica, et al.
(författare)
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Faster progression to AIDS and AIDS-related death among seroincident individuals infected with recombinant HIV-1 A3/CRF02_AG compared to sub subtype A3.
- 2014
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Ingår i: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 209:5, s. 721-728
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Tidskriftsartikel (refereegranskat)abstract
- HIV-1 is divided into different subtypes and circulating recombinant forms (CRFs) but the impact of HIV-1 subtype/CRF on disease progression is not fully understood. We determined the HIV-1 subtype/CRF of 152 seroincident individuals from Guinea-Bissau, based on the C2-V3 region of env. Rate of disease progression was measured as time from estimated seroconversion to AIDS and AIDS-related death. Hazard ratios (HRs) were calculated using a Cox proportional hazard model, adjusting for gender and age at seroconversion. The major subtypes/CRFs identified were CRF02_AG (53%), A3 (29%) and A3/02 (a recombinant of A3 and CRF02_AG) (13%). Infection with A3/02 was associated with a close to 3-fold increased risk of AIDS and AIDS-related death compared to A3 (HR=2.6 [P=0.011] and 2.9 [P=0.032], respectively). The median estimated time from seroconversion to AIDS and AIDS-related death was 5.0 and 8.0 years for A3/02, 6.2 and 9.0 years for CRF02_AG and 7.2 and 11.3 years for A3. Our results show that there are significant differences in disease progression between HIV-1 A-like subtypes/CRFs. Individuals infected with the A3/02 recombinant have among the fastest progression rates to AIDS reported to date. Determining the HIV-1 subtype of infected individuals could be of importance in the management of HIV-1 infections.
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| 9. |
- 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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