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A newer integrase strand transfer inhibitor (INSTI) cabotegravir was recently approved for both therapy and prophylaxis and can play an essential role in the fight against AIDS. It shares similar resistance profile to dolutegravir, the cornerstone of Brazilian antiretroviral (ARV) treatment, with about 600 thousand people living with HIV in Brazil currently on regimens that contain this INSTI. Health services in the São Paulo metropolitan area are responsible for a large proportion of ARV dispensation in the country. Estimating transmitted drug resistance mutation (TDRM) in the area before cabotegravir introduction may provide a useful baseline information. Partial HIV-1 pol gene was sequenced (Sanger) from 192 newly diagnosed individuals from São Paulo and nearby cities (2020 to March 2023) at integrase, with 85 also at protease/reverse transcriptase regions. Retrotranscribed plasma RNA, amplified with nested PCR, was edited (Recall or Sequencher) and analyzed at Rega and Stanford db. Surveillance drug resistance mutations (SDRM) to INSTI class was detected in three cases (1.6%; 95% CI: 0.5%-5%), two E138K and one R263K, with 7.8% (95% CI: 5%-13%) with resistance mutations (major or accessory). SDRM for nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, and PI classes were identified in 7 (8.2% CI: 95% 4%-16%) cases. Subtype B predominated (69%), followed by subtype C (16%), now the second most prevalent infection in this area. Among 131 patients treated for over 6 months, 92% were virally suppressed below 200 copies/mL, with low TCD4 counts independently associated to failure. SDRM to INSTI class is rare in the area. Intermediate rates of transmitted resistance to other ARV classes are comparable to previous estimates. Viral suppression rates may depend on TCD4 counts, another negative impact of late diagnosis in care that deserves more attention.

The increase in the construction of mega dams in tropical basins is considered a threat to freshwater fish diversity. Although difficult to detect in conventional monitoring programs, rheophilic species and those reliant on shallow habitats comprise a large proportion of fish diversity in tropical basins and are among the most sensitive species to hydropower impacts. We used Baited Remote Underwater Video (BRUV), an innovative, non-invasive sampling technique, to record the impacts caused by Belo Monte, the third largest hydropower project in the world, on fishes inhabiting fast waters in the Xingu River. BRUV were set in a river stretch of ~ 240 km for 7 years, 2 before and 5 after the Belo Monte operation. We explored the spatial and temporal variation in fish diversity (α, β, and γ) and abundance (MaxN) using generalized additive models. We also investigated the variation of environmental variables and tested how much information we gained by including them in the diversity and abundance models. Belo Monte altered the flow regime, water characteristics, and fishery yield in the Xingu, resulting in changes in the fish community structure. Temporally, we observed sharp declines in α diversity and abundance, far exceeding those from a previous study conducted with more conventional sampling methods (i.e., catch-based) in the region. γ-diversity was also significantly reduced, but we observed a non-expected increase in β diversity over time. The latter may be associated with a reduction in river connectivity and an increase in environmental heterogeneity among river sectors. Unexpected signs of recovery in diversity metrics were observed in the last years of monitoring, which may be associated with the maintenance of flow levels higher than those previously planned. These results showed that BRUV can be a useful and sensitive tool to monitor the impacts of dams and other enterprises on fish fauna from clear-water rivers. Moreover, this study enhances our comprehension of the temporal variations in freshwater fish diversity metrics and discusses the prevalent assumption that a linear continuum in fish-structure damage associated with dam impoundments may exhibit temporal non-linearity., (© 2024. The Author(s).)