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Bartolo I.,University of Lisbon | Bartolo I.,Instituto Superior Of Ciencias Da Saude Egas Moniz | Zakovic S.,Instituto Superior Of Ciencias Da Saude Egas Moniz | Martin F.,University of Lisbon | And 9 more authors.
PLoS ONE | Year: 2014

Objectives: To assess HIV-1 diversity, transmission dynamics and prevalence of transmitted drug resistance (TDR) in Angola, five years after ART scale-up. Copyright:Methods: Population sequencing of the pol gene was performed on 139 plasma samples collected in 2009 from drug-naive HIV-1 infected individuals living in Luanda. HIV-1 subtypes were determined using phylogenetic analysis. Drug resistance mutations were identified using the Calibrated Population Resistance Tool (CPR). Transmission networks were determined using phylogenetic analysis of all Angolan sequences present in the databases. Evolutionary trends were determined by comparison with a similar survey performed in 2001.Results: 47.1% of the viruses were pure subtypes (all except B), 47.1% were recombinants and 5.8% were untypable. The prevalence of subtype A decreased significantly from 2001 to 2009 (40.0% to 10.8%, P50.0019) while the prevalence of unique recombinant forms (URFs) increased>2-fold (40.0% to 83.1%, P<0.0001). The most frequent URFs comprised untypable sequences with subtypes H (U/H, n=7, 10.8%), A (U/A, n=6, 9.2%) and G (G/U, n=4, 6.2%). Newly identified U/H recombinants formed a highly supported monophyletic cluster suggesting a local and common origin. TDR mutation K103N was found in one (0.7%) patient (1.6% in 2001). Out of the 364 sequences sampled for transmission network analysis, 130 (35.7%) were part of a transmission network. Forty eight transmission clusters were identified; the majority (56.3%) comprised sequences sampled in 2008-2010 in Luanda which is consistent with a locally fuelled epidemic. Very low genetic distance was found in 27 transmission pairs sampled in the same year, suggesting recent transmission events.Conclusions: Transmission of drug resistant strains was still negligible in Luanda in 2009, five years after the scale-up of ART. The dominance of small and recent transmission clusters and the emergence of new URFs are consistent with a rising HIV-1 epidemics mainly driven by heterosexual transmission. © 2014 Bártolo et al. Source

Santos A.,Clinica Sagrada Esperanca | Clemente S.,Hospital da Divina Providencia | Bartolo I.,CiiEM | Palladino C.,Hospital General Universitario Gregorio Maranon | And 5 more authors.
Diagnostic Microbiology and Infectious Disease | Year: 2011

The rapid test VIKIA HIV1/2 was evaluated in 210 Angolan subjects infected with multiple HIV-1 subtypes and complex recombinant forms and 225 seronegative individuals. All infected subjects tested positive (100% sensitivity); all seronegative subjects tested negative (100% specificity). VIKIA HIV1/2 is highly specific and sensitive even in highly complex epidemics. © 2011 Elsevier Inc. Source

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