The concentration of tuberculosis within Paraguay's incarcerated and Indigenous populations, 2018-2022.

While incidence of tuberculosis (TB) has decreased globally, in Paraguay, considered a medium-incidence country by the WHO, TB incidence has increased slightly from 42 per 100,000 in 2010 to 46 per 100,000 in 2022. We conducted a retrospective study of TB cases notified to the Paraguay National Program for Tuberculosis Control (NPTC) from 2018 to 2022 and quantified trends in specific populations identified as vulnerable. Of the 13,725 TB cases notified in Paraguay from 2018 to 2022, 2,331 (17%) occurred among incarcerated individuals and 1,743 (12.7%) occurred among self-identified Indigenous individuals. In 2022, the relative risk of TB was 87 and 6.4 among the incarcerated and Indigenous populations, compared with the non-incarcerated and non-Indigenous populations respectively. We found significant heterogeneity in TB incidence across Paraguay's 17 departments. Our findings highlight the urgency of expanding access to TB diagnosis, treatment, and prevention in populations at heightened risk of TB in Paraguay.

Seroprevalence of Treponema pallidum infection among high-risk populations from Brazil.

Syphilis is a significant public health concern worldwide. According to the 2020 estimates, nearly 7.1 million new cases of syphilis have been reported globally, with over 30 % of these cases reported from American nations, particularly Brazil. Concerns have been raised regarding the susceptibility of specific groups to syphilis due to challenges and vulnerabilities that place these groups at a higher risk of infections or complications in the treatment outcomes. The present study aimed to compare the seroprevalence and the factors associated with syphilis among such high-risk groups. The study was designed as a cross-sectional one and was conducted with pregnant women, people living with HIV (PLHIV), people living with tuberculosis (PLTB), indigenous and healthy populations in Mato Grosso do Sul, Brazil. The study was conducted between June 2019 and August 2022, during which the included patients were subjected to treponemal and non-treponemal serological assays. The study also included a survey conducted through a self-reported questionnaire to collect information regarding the participants' demographics and sexual behaviors. A total of 550 samples were collected, with 110 participants in each of the five groups. The results of the study revealed that the seroprevalence of Treponema pallidum infection in pregnant women, PLHIV, PLTB, indigenous and healthy populations of the study region was 10 % (n = 11/110), 41.81 % (n = 46/110), 17.27 % (n = 19/110), 5.45 % (n = 6/110), and 8.18 % (n = 9/110), respectively. Homosexual orientation (p = 0.04) and a history of sexually transmitted infection (STI) (p = 0.01) were associated with the seroprevalence of T. pallidum infection in PLHIV. However, no such associations were noted in the remaining four groups. The seroprevalence of T. pallidum infection was observed to vary significantly among the different high-risk groups, which highlighted the persistent concern of syphilis, particularly among vulnerable populations. These findings underscore the significance of focused interventions and public health strategies customized to the specific requirements of each of the groups evaluated in the present study to decrease the number of cases of syphilis and thereby prevent future complications in patients with other serious infections.

Effectiveness of the fourth dose of COVID-19 vaccines against severe COVID-19 among adults 40 years or older in Brazil: a population-based cohort study.

Background: The emergence of COVID-19 variants with immune scape and the waning of primary vaccine schemes effectiveness have prompted many countries to indicate first and second booster COVID-19 vaccine doses to prevent severe COVID-19. However, current available evidence on second booster dose effectiveness are mostly limited to high-income countries, older adults, and mRNA-based vaccination schemes scenarios. We aimed to investigate the relative vaccine effectiveness (rVE) of the fourth dose compared to three doses for severe COVID-19 outcomes in Brazil; and compare the rVE of a fourth dose with an mRNA vaccine compared to adenovirus-based product in the same settings. Methods: We performed a target emulated trial using a population-based cohort of individuals aged 40 years or older who have received a homologous primary scheme of CoronaVac, ChAdOx1, or BNT162b2, and any third dose product and were eligible for the fourth dose in Brazil. The primary outcome was COVID-19 associated hospitalization or death. We built Cohort A matching individuals vaccinated with a fourth dose to individuals who received three doses to estimate the rVE of the fourth dose. We built Cohort B, a subset of Cohort A, matching mRNA-based (mRNA) to adenovirus-based fourth dose vaccinated individuals to compare their relative hazards for severe COVID-19. Findings: 46,693,484 individuals were included in Cohort A and 6,763,016 in Cohort B. 45% of them were aged between 40 and 60 years old, and 48% between 60 and 79 years old. In Cohort A, the most common previous series was a ChAdOx1 two-dose followed by BNT162b2 (44%), and a CoronaVac two-dose followed by a BNT162b2 (36%). Among those fourth dose vaccinated, 36.9% received ChAdOx1, 32.7% Ad26.COV2.S, 25.8% BNT162b2, and 4.7% CoronaVac. In Cohort B, among those who received an adenovirus fourth dose, 53.7% received ChAdOx1 and 46.3% received Ad26.COV2.S. The estimated rVE for the primary outcome of four doses compared to three doses was 44.1% (95% CI 42.3-46.0), with some waning during follow-up (rVE 7-60 days 46.8% [95% CI 44.4-49.1], rVE after 120 days 33.8% [95% CI 18.0-46.6]). Among fourth dose vaccinated individuals, mRNA-based vaccinated individuals had lower hazards for hospitalization or death compared to adenovirus-vaccinated individuals (HR 0.81, 95% CI 0.75-0.87). After 120 days, no difference in hazards between groups was observed (HR 1.35, 95% CI 0.93-1.97). Similar findings were observed for hospitalization and death separately, except no evidence for differences between fourth dose brands for death in Cohort B. Interpretation: In a heterogeneous scenario of primary and first booster vaccination combinations, a fourth dose provided meaningful and durable protection against severe COVID-19 outcomes. Compared to adenovirus-based booster, a fourth dose wild-type mRNA vaccine was associated with immediate lower hazards of hospitalization or death unsustained after 120 days. Funding: None.

Bacille Calmette-Guérin vaccination to prevent febrile and respiratory illness in adults (BRACE): secondary outcomes of a randomised controlled phase 3 trial.

Background: Bacille Calmette-Guérin (BCG) vaccination has off-target (non-specific) effects that are associated with protection against unrelated infections and decreased all-cause mortality in infants. We aimed to determine whether BCG vaccination prevents febrile and respiratory infections in adults. Methods: This randomised controlled phase 3 trial was done in 36 healthcare centres in Australia, Brazil, the Netherlands, Spain, and the United Kingdom. Healthcare workers were randomised to receive BCG-Denmark (single 0.1 ml intradermal injection) or no BCG in a 1:1 ratio using a web-based procedure, stratified by stage, site, age, and presence of co-morbidity. The difference in occurrence of febrile or respiratory illness were measured over 12 months (prespecified secondary outcome) using the intention-to-treat (ITT) population. This trial is registered with ClinicalTrials.gov, NCT04327206. Findings: Between March 30, 2020, and April 1, 2021, 6828 healthcare workers were randomised to BCG-Denmark (n = 3417) or control (n = 3411; no intervention or placebo) groups. The 12-month adjusted estimated risk of ≥1 episode of febrile or respiratory illness was 66.8% in the BCG group (95% CI 65.3%-68.2%), compared with 63.4% in the control group (95% CI 61.8%-65.0%), a difference of +3.4 percentage points (95% CI +1.3% to +5.5%; p 0.002). The adjusted estimated risk of a severe episode (defined as being incapacitated for ≥3 consecutive days or hospitalised) was 19.4% in the BCG group (95% CI 18.0%-20.7%), compared with 18.8% in the control group (95% CI 17.4%-20.2%) a difference of +0.6 percentage points (95% CI -1.3% to +2.5%; p 0.6). Both groups had a similar number of episodes of illness, pneumonia, and hospitalisation. There were three deaths, all in the control group. There were no safety concerns following BCG vaccination. Interpretation: In contrast to the beneficial off-target effects reported following neonatal BCG in infants, a small increased risk of symptomatic febrile or respiratory illness was observed in the 12 months following BCG vaccination in adults. There was no evidence of a difference in the risk of severe disease. Funding: Bill & Melinda Gates Foundation, Minderoo Foundation, Sarah and Lachlan Murdoch, the Royal Children's Hospital Foundation, Health Services Union NSW, the Peter Sowerby Foundation, SA Health, the Insurance Advisernet Foundation, the NAB Foundation, the Calvert-Jones Foundation, the Modara Pines Charitable Foundation, the UHG Foundation Pty Ltd, Epworth Healthcare, the National Health and Medical Research Council, the Swiss National Science Foundation and individual donors.

Excess tuberculosis risk during and following incarceration in Paraguay: a retrospective cohort study.

Background: The increased risk of tuberculosis (TB) among people deprived of liberty (PDL) is due to individual and institution-level factors. We followed a cohort of PDL from 5 prisons in Paraguay to describe the risk of TB during incarceration and after they were released. Methods: We linked a 2013 national census of prisons with TB records from the TB Program from 2010 to 2021 to identify TB notifications among incarcerated and formerly incarcerated individuals. We used multivariable Cox regression models to quantify the risk of TB during and following incarceration and to identify risk factors associated with TB. Findings: Among 2996 individuals incarcerated, 451 (15.1%) were diagnosed with TB. Of these, 262 (58.1%) cases occurred during incarceration and 189 (41.9%) occurred in the community after release. In prison, the hazard ratio of developing TB was 1.97 (95% CI: 1.52-2.61) after six months of incarceration and increased to 2.78 (95% CI: 1.82-4.24) after 36 months compared with the first six months. The overall TB notification rate was 2940 per 100,000 person-years. This rate increased with the duration of incarceration from 1335 per 100,000 person-years in the first year to 8455 per 100,000 person-years after 8 years. Among former prisoners, the rate of TB decreased from 1717 in the first year after release to 593 per 100 000 person-years after 8 years of follow up. Interpretation: Our study shows the alarming risk of TB associated with prison environments in Paraguay, and how this risk persists for years following incarceration. Effective TB control measures to protect the health of people during and following incarceration are urgently needed. Funding: Paraguay National Commission of Science and Technology grant CONACYT PIN 15-705 (GS, GES, SA).

Factors influencing adverse events following COVID-19 vaccination.

Various novel platform technologies have been used for the development of COVID-19 vaccines. In this nested cohort study among healthcare workers in Australia and Brazil who received three different COVID-19-specific vaccines, we (a) evaluated the incidence of adverse events following immunization (AEFI); (b) compared AEFI by vaccine type, dose and country; (c) identified factors influencing the incidence of AEFI; and (d) assessed the association between reactogenicity and vaccine anti-spike IgG antibody responses. Of 1302 participants who received homologous 2-dose regimens of ChAdOx1-S (Oxford-AstraZeneca), BNT162b2 (Pfizer-BioNTech) or CoronaVac (Sinovac), 1219 (94%) completed vaccine reaction questionnaires. Following the first vaccine dose, the incidence of any systemic reaction was higher in ChAdOx1-S recipients (374/806, 46%) compared with BNT162b2 (55/151, 36%; p = 0.02) or CoronaVac (26/262, 10%; p < 0.001) recipients. After the second vaccine dose, the incidence of any systemic reaction was higher in BNT162b2 recipients (66/151, 44%) compared with ChAdOx1-S (164/806, 20%; p < 0.001) or CoronaVac (23/262, 9%; p < 0.001) recipients. AEFI risk was higher in younger participants, females, participants in Australia, and varied by vaccine type and dose. Prior COVID-19 did not impact the risk of AEFI. Participants in Australia compared with Brazil reported a higher incidence of any local reaction (170/231, 74% vs 222/726, 31%, p < 0.001) and any systemic reaction (171/231, 74% vs 328/726, 45%, p < 0.001), regardless of vaccine type. Following a primary course of ChAdOx1-S or CoronaVac vaccination, participants who did not report AEFI seroconverted at a similar rate to those who reported local or systemic reactions. In conclusion, we found that the incidence of AEFI was influenced by participant age and COVID-19 vaccine type, and differed between participants in Australia and Brazil.

Serial Mass Screening for Tuberculosis Among Incarcerated Persons in Brazil.

BACKGROUND: An active search for tuberculosis cases through mass screening is widely described as a tool to improve case detection in hyperendemic settings. However, its effectiveness in high-risk populations, such as incarcerated people, is debated. METHODS: Between 2017 and 2021, 3 rounds of mass screening were carried out in 3 Brazilian prisons. Social and health questionnaires, chest X-rays, and Xpert MTB/RIF were performed. RESULTS: More than 80% of the prison population was screened. Overall, 684 cases of pulmonary tuberculosis were diagnosed. Prevalence across screening rounds was not statistically different. Among incarcerated persons with symptoms, the overall prevalence of tuberculosis per 100 000 persons was 8497 (95% confidence interval [CI], 7346-9811), 11 115 (95% CI, 9471-13 082), and 7957 (95% CI, 6380-9882) in screening rounds 1, 2, and 3, respectively. Similar to our overall results, there were no statistical differences between screening rounds and within individual prisons. We found no statistical differences in Computer-Aided Detection for TB version 5 scores across screening rounds among people with tuberculosis-the median scores in rounds 1, 2, and 3 were 82 (interquartile range [IQR], 63-97), 77 (IQR, 60-94), and 81 (IQR, 67-92), respectively. CONCLUSIONS: In this environment with hyperendemic rates of tuberculosis, 3 rounds of mass screening did not reduce the overall tuberculosis burden. In prisons, where a substantial number of tuberculosis cases is undiagnosed annually, a range of complementary interventions and more frequent tuberculosis cases screening may be required.

Effect of BCG vaccination against Mycobacterium tuberculosis infection in adult Brazilian health-care workers: a nested clinical trial.

BACKGROUND: The effectiveness of BCG vaccine for adult pulmonary tuberculosis remains uncertain. In this study, we aimed to evaluate the effect of vaccination with BCG-Denmark to prevent initial and sustained interferon-γ release assay conversion in Brazilian health-care workers. METHODS: This substudy is a nested randomised controlled trial embedded within the BRACE trial (NCT04327206). Specifically, this substudy enrolled Brazilian health-care workers (aged ≥18 years) from three sites in Brazil (Manaus, Campo Grande, and Rio de Janeiro) irrespective of previously receiving BCG vaccination. Participants were excluded if they had contraindications to BCG vaccination, more than 1 month of treatment with specific tuberculosis treatment drugs, previous adverse reactions to BCG, recent BCG vaccination, or non-compliance with assigned interventions. Those eligible were randomly assigned (1:1) to either the BCG group (0·1 mL intradermal injection of BCG-Denmark [Danish strain 1331; AJ Vaccines, Copenhagen]) or the placebo group (intradermal injection of 0·9% saline) using a web-based randomisation process in variable-length blocks (2, 4, or 6), and were stratified based on the study site, age (<40, ≥40 to <60, ≥60 years), and comorbidity presence (diabetes, chronic respiratory disease, cardiac condition, hypertension). Sealed syringes were used to prevent inadvertent disclosure of group assignments. The QuantiFERON-TB Gold (QFT) Plus test (Qiagen; Hilden, Germany) was used for baseline and 12-month tuberculosis infection assessments. The primary efficacy outcome was QFT Plus conversion (≥0·35 IU/mL) by 12 months following vaccination in participants who had a negative baseline result (<0·35 IU/mL). FINDINGS: Between Oct 7, 2020, and April 12, 2021, 1985 (77·3%) of 2568 participants were eligible for QFT Plus assessment at 12 months and were included in this substudy; 996 (50·2%) of 1985 were in the BCG group and 989 (49·8%) were in the placebo group. Overall, 1475 (74·3%) of 1985 participants were women and 510 (25·7%) were men, and the median age was 39 years (IQR 32-47). During the first 12 months, QFT Plus conversion occurred in 66 (3·3%) of 1985 participants, with no significant differences by study site (p=0·897). Specifically, 34 (3·4%) of 996 participants had initial QFT conversion in the BCG group compared with 32 (3·2%) of 989 in the placebo group (risk ratio 1·09 [95% CI 0·67-1·77]; p=0·791). INTERPRETATION: BCG-Denmark vaccination did not reduce initial QFT Plus conversion risk in Brazilian health-care workers. This finding underscores the need to better understand tuberculosis prevention in populations at high risk. FUNDING: Bill & Melinda Gates Foundation, the Minderoo Foundation, Sarah and Lachlan Murdoch, the Royal Children's Hospital Foundation, Health Services Union NSW, the Peter Sowerby Foundation, SA Health, the Insurance Advisernet Foundation, the NAB Foundation, the Calvert-Jones Foundation, the Modara Pines Charitable Foundation, the United Health Group Foundation, Epworth Healthcare, and individual donors. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.

Seroprevalence Of SARS-COV-2 infection in asymptomatic indigenous from the largest Brazilian periurban area.

This study assessed the seroprevalence of SARS-CoV-2 in 496 asymptomatic individuals from Mato Grosso do Sul, located in Dourados, the largest periurban indigenous area in Brazil, from January 25 to February 4, 2021. The volunteers participated before receiving their first dose of the CoronaVac inactivated vaccine. For screening, blood samples were collected and analyzed using SARS-CoV-2 rapid tests and the enzyme-linked immunosorbent assay (ELISA). We observed varying trends in total anti-SARS-CoV-2 antibodies across different variables. Seropositivity among the participants tested was 63.70% (316/496) using the rapid test and 52.82% (262/496) were positive using the ELISA method. The majority of participants identified with the Guarani-Kaiowá ethnic group, with 66.15% (217/328), and other ethnic groups with 58.84% (193/328). The median age of the subjects was 30.5 years, with 79.57% (261/328) being femaleThis research showed the elevated seroprevalence of SARS-CoV-2 antibodies in asymptomatic Brazilians. The findings indicate a high seropositivity rate among the asymptomatic indigenous population of Midwest Brazil. This underscores the overlooked status of these communities and underscores the need for targeted national initiatives that emphasize the protection of vulnerable ethnic groups in the fight against COVID-19.

Genomic characterization of SARS-CoV-2 from an indigenous reserve in Mato Grosso do Sul, Brazil.

Background: The COVID-19 pandemic had a major impact on indigenous populations. Understanding the viral dynamics within this population is essential to create targeted protection measures. Methods: A total of 204 SARS-CoV-2 positive samples collected between May 2020 and November 2021 from an indigenous area in Mato Grosso do Sul (MS), Midwestern Brazil, were screened. Samples were submitted to whole genome sequencing using the Nanopore sequencing platform. Clinical, demographic, and phylogenetic data were analyzed. Results: We found the co-circulation of six main SARS-CoV-2 lineages in the indigenous population, with the Zeta lineage being the most prevalent (27.66%), followed by B.1.1 (an ancestral strain) (20.21%), Gamma (14.36%) and Delta (13.83%). Other lineages represent 45.74% of the total. Our phylogenetic reconstruction indicates that multiple introduction events of different SARS-CoV-2 lineages occurred in the indigenous villages in MS. The estimated indigenous population mortality rate was 1.47%. Regarding the ethnicity of our cohort, 64.82% belong to the Guarani ethnicity, while 33.16% belong to the Terena ethnicity, with a slightly higher prevalence of males (53.43%) among females. Other ethnicities represent 2.01%. We also observed that almost all patients (89.55%) presented signs and symptoms related to COVID-19, being the most prevalent cough, fever, sore throat, and headache. Discussion: Our results revealed that multiple independent SARS-CoV-2 introduction events had occurred through time, probably due to indigenous mobility, since the villages studied here are close to urban areas in MS. The mortality rate was slightly below of the estimation for the state in the period studied, which we believe could be related to the small number of samples evaluated, the underreporting of cases and deaths among this population, and the inconsistency of secondary data available for this study. Conclusion: In this study, we showed the circulation of multiple SARS-CoV-2 variants in this population, which should be isolated and protected as they belong to the most fragile group due to their socioeconomic and cultural disparities. We reinforce the need for constant genomic surveillance to monitor and prevent the spread of new emerging viruses and to better understand the viral dynamics in these populations, making it possible to direct specific actions.

Prioritizing persons deprived of liberty in global guidelines for tuberculosis preventive treatment.

In this Policy Forum piece, Aditya Narayan and colleagues discuss the challenges and opportunities for tuberculosis preventive treatment in carceral settings.

Bacillus Calmette-Guérin vaccination for protection against recurrent herpes labialis: a nested randomised controlled trial.

Background: Recurrences of herpes simplex virus (HSV) in the orofacial region (herpes labialis or cold sores) impact quality-of-life. We aimed to study whether the bacille Calmette-Guérin (BCG) vaccine can attenuate cold sore recurrences through off-target immunomodulatory effects. Methods: In this nested randomised controlled trial within the multicentre, phase 3 BRACE trial, 6828 healthcare workers were randomised in 36 sites in Australia, the Netherlands, Spain, the United Kingdom and Brazil, to receive BCG-Denmark or no BCG (1:1 ratio using a web-based procedure) and followed for 12 months with 3-monthly questionnaires. Exclusion criteria included contraindication to BCG vaccine or previous vaccination with BCG within the past year, any other live-attenuated vaccine within the last month, or any COVID-specific vaccine. The intervention group received one intradermal dose of 0.1 mL of BCG-Denmark corresponding to 2-8 x 105 colony forming units of Mycobacterium bovis, Danish strain 1331. The primary outcome was the difference in restricted mean survival time (i.e., time to first cold-sore recurrence), in participants with frequent recurrent herpes labialis (≥4 recurrences/year), analysed by intention-to-treat. Secondary outcomes addressed additional questions, including analyses in other sub-populations. Adverse events were monitored closely during the first 3 months and were reported in all participants who received one dose of study drug according to intervention received. The BRACE trial is registered with ClinicalTrials.gov, NCT04327206. Findings: Between March 30, 2020 and February 18, 2021, 84 individuals with frequent recurrent cold sores were randomly assigned to BCG (n = 38) or control (n = 46). The average time to first cold-sore recurrence was 1.55 months longer in the BCG group (95% CI 0.27-2.82, p = 0.02) than the control group (hazard ratio 0.54, 95% CI 0.32-0.91; intention-to-treat). The beneficial effect of BCG was greater in the as-treated population (difference 1.91 months, 95% CI 0.69-3.12, p = 0.003; hazard ratio 0.45, 95% CI 0.26-0.76). In prespecified subgroup analyses, only sex modified the treatment effect (interaction p = 0.007), with benefit restricted to males. Over 12 months, a greater proportion of participants in the BCG group compared with the control group reported a decrease in duration (61% vs 21%), severity (74% vs 21%), frequency (55% vs 21%), and impact on quality of life (42% vs 15%) of cold sore recurrences. In participants who had ever had a cold sore, there was also a decrease in self-reported burden of recurrences in the BCG group. In participants who had never had a cold sore, there was an increased risk of a first episode in the BCG group (risk difference 1.4%; 95% CI 0.3-2.6%, p = 0.02). There were no safety concerns. Interpretation: BCG-Denmark vaccination had a beneficial effect on herpes labialis, particularly in males with frequent recurrences, but may increase the risk of a first cold sore. Funding: Bill & Melinda Gates Foundation, the Minderoo Foundation, Sarah and Lachlan Murdoch, the Royal Children's Hospital Foundation, Health Services Union NSW, the Peter Sowerby Foundation, SA Health, the Insurance Advisernet Foundation, the NAB Foundation, the Calvert-Jones Foundation, the Modara Pines Charitable Foundation, the UHG Foundation Pty Ltd, Epworth Healthcare, and individual donors.

Dengue Fever Surveillance in Mato Grosso do Sul: Insights from Genomic Analysis and Implications for Public Health Strategies.

Since its discovery in early 1916, dengue fever, a common vector-borne illness in Brazil, has resulted in extensive urban outbreaks and poses a serious threat to the public's health. Understanding the dynamics of Dengue Virus (DENV) serotypes circulating in different regions of Brazil is essential for implementing effective disease control and prevention measures. In response to this urgent need, we conducted an on-site training program in genomic surveillance in collaboration with the Central Laboratory of Health and the Secretary of Health of the Mato Grosso do Sul state. This initiative resulted in the generation of 177 DENV genome sequences collected between May 2021 and May 2022, a period during which over 11,391 dengue fever cases were reported in the state. Through this approach, we were able to identify the co-circulation of two different dengue serotypes (DENV1 and DENV2) as well as the existence of diverse viral lineages within each genotype, suggesting that multiple introduction events of different viral strains occurred in the region. By integrating epidemiological data, our findings unveiled temporal fluctuations in the relative abundance of different serotypes throughout various epidemic seasons, highlighting the complex and changing dynamics of DENV transmission throughout time. These findings demonstrate the value of ongoing surveillance activities in tracking viral transmission patterns, monitoring viral evolution, and informing public health actions.

Prevalence of HIV-1 infection and associated characteristics in a Brazilian indigenous population: a cross-sectional study.

Background: Despite significant progress in the areas of prevention, diagnosis, and treatment, HIV continues to result in a substantial number of fatalities on a global scale each year. Gaining insights from epidemiological data can prove instrumental in the development of health promotion strategies, particularly within vulnerable populations, such as indigenous groups. Consequently, our study aimed to investigate the prevalence of HIV infection within the indigenous population residing in the second-largest region of Brazil. Additionally, we sought to explore the subtypes of HIV-1 and detect any drug-resistance mutations present within this population. Methods: In this cross-sectional study, we aimed to evaluate the prevalence of HIV-1 infection and explore its associated characteristics within the indigenous population residing in the villages of Jaguapiru and Bororó, located in the Dourados area of Mato Grosso do Sul (MS), Brazil. Blood samples were collected for rapid HIV screening, serological tests, nucleic acid amplification, and HIV subtyping. Additionally, the HIV-1 viral load and CD4+ T lymphocyte count of the people living with HIV (PLHIV) were assessed at the time of recruitment and 24 weeks later. Findings: Out of the 2190 invited individuals, 1927 (88%) were included in this study. The average age of the participants was 34.2 (±13.8) years, with a majority of 74% being female. Moreover, 68.44% of the participants identified themselves as belonging to the Guarani-Kaiowa ethnic group. HIV seroprevalence was 0.93% (18/1927), and 73.22% (1411/1927) were unaware of their serological status. The prevalence of HIV-1 was higher in single indigenous people [10/617 (1.62%)], who received government benefits [14/1021 (1.37%)], had less than five years of formal education [11/685 (1.61%)], had sexual intercourse with users of injectable drugs [2/21 (9.52%)], with history of sexually transmitted infections (STIs) [10/62 (16.2%)] and incarceration [3/62 (4.84%)]. Of 18 positive samples, 44.4% (8/18) were successfully amplified, and HIV-1 subtype C was prevalent. Furthermore, we identified HIV-1 drug resistance mutations in four patients, specifically from the classes of Protease Inhibitor, Nucleoside Reverse Transcriptase Inhibitor, and Non-Nucleoside Reverse Transcriptase Inhibitor. Notably, three of these patients exhibited a high viral load even after 24 weeks of undergoing antiretroviral therapy. Out of the 18 PLHIV, 66.66% (12/18) had a viral load below 1000 copies/mL, while 50% (9/18) had a CD4+ T lymphocytes count greater than 350 cells/mL after 24 weeks of treatment. Interpretation: Despite the concerted efforts to control HIV infection, the prevalence observed in the indigenous population under study surpassed that reported in other Brazilian indigenous groups. This disparity highlights the disproportionate impact of the disease on this particular group. The detection of drug-resistance mutations further emphasizes the critical need to expand diagnostic coverage, closely monitor treatment strategies, and maintain ongoing molecular surveillance. These measures are imperative for enhancing HIV management within this vulnerable population. Funding: This study was partially funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Apoio ao Desenvolvimento do Ensino, Ciência e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Secretaria do Estado de Saúde (SES) of Governo do Estado de Mato Grosso do Sul, and Universidade Federal da Grande Dourados (UFGD).

Pan-American Guidelines for the treatment of SARS-CoV-2/COVID-19: a joint evidence-based guideline of the Brazilian Society of Infectious Diseases (SBI) and the Pan-American Association of Infectious Diseases (API).

BACKGROUND: Since the beginning of the COVID-19 pandemic, therapeutic options for treating COVID-19 have been investigated at different stages of clinical manifestations. Considering the particular impact of COVID-19 in the Americas, this document aims to present recommendations for the pharmacological treatment of COVID-19 specific to this population. METHODS: Fifteen experts, members of the Brazilian Society of Infectious Diseases (SBI) and the Pan-American Association of Infectious Diseases (API) make up the panel responsible for developing this guideline. Questions were formulated regarding prophylaxis and treatment of COVID-19 in outpatient and inpatient settings. The outcomes considered in decision-making were mortality, hospitalisation, need for mechanical ventilation, symptomatic COVID-19 episodes, and adverse events. In addition, a systematic review of randomised controlled trials was conducted. The quality of evidence assessment and guideline development process followed the GRADE system. RESULTS: Nine technologies were evaluated, and ten recommendations were made, including the use of tixagevimab + cilgavimab in the prophylaxis of COVID-19, tixagevimab + cilgavimab, molnupiravir, nirmatrelvir + ritonavir, and remdesivir in the treatment of outpatients, and remdesivir, baricitinib, and tocilizumab in the treatment of hospitalised patients with severe COVID-19. The use of hydroxychloroquine or chloroquine and ivermectin was discouraged. CONCLUSION: This guideline provides recommendations for treating patients in the Americas following the principles of evidence-based medicine. The recommendations present a set of drugs that have proven effective in the prophylaxis and treatment of COVID-19, emphasising the strong recommendation for the use of nirmatrelvir/ritonavir in outpatients as the lack of benefit from the use of hydroxychloroquine and ivermectin.