25 research outputs found

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.

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    BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

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    Background A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. Methods This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. Findings Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. Interpretation ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials

    Cytokine profile and proviral load among Japanese immigrants and non-Japanese infected with HTLV-1 in a non-endemic area of Brazil

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    Submitted by Sandra Infurna ([email protected]) on 2017-07-06T10:57:14Z No. of bitstreams: 1 louise_zanella_etal_IOC_2017.pdf: 2111205 bytes, checksum: 46a343e352837e56495a852d5ad4fffd (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2017-07-06T11:14:43Z (GMT) No. of bitstreams: 1 louise_zanella_etal_IOC_2017.pdf: 2111205 bytes, checksum: 46a343e352837e56495a852d5ad4fffd (MD5)Made available in DSpace on 2017-07-06T11:14:44Z (GMT). No. of bitstreams: 1 louise_zanella_etal_IOC_2017.pdf: 2111205 bytes, checksum: 46a343e352837e56495a852d5ad4fffd (MD5) Previous issue date: 2017Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil / Fundação Oswaldo Cruz. Campo Grande, MS, Brasil.Universidade Federal de Mato Grosso do Sul. Campo Grande, MS, Brasil / Fundação Oswaldo Cruz. Campo Grande, MS, Brasil.The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL) in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs). The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs) and 18 healthy controls (HCs) in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host genetic background to better understand the low frequency of HAM/TSP in Japanese HTLV-1-infected individuals

    Human T-cell leukemia virus type 1 infection among Japanese immigrants and their descendants living in Southeast Brazil: A call for preventive and control responses.

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    Human T-cell leukemia virus type 1 (HTLV-1) has worldwide distribution and is considered endemic in southwestern Japan. HTLV-1 infection has been associated with adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) besides other diseases. This cross-sectional study aimed to investigate the prevalence, risk factors and molecular characterization of HTLV-1, among the world's largest population of Japanese immigrants and their descendants outside of Japan, in São Paulo, Southeast Brazil, as well as to analyze the phylogenetic relationship among isolates of HTLV-1. From July to December 2017, 2,139 individuals from five Japanese associations were interviewed and submitted to blood collection. All serum samples were first tested for the presence of anti-HTLV-1/2 antibodies by ELISA and then peripheral blood from individuals with positive serological results were analyzed for the presence of HTLV-1 5'LTR proviral DNA. Partial sequencing of the 5'LTR region of HTLV-1 proviral DNA was performed by Sanger. The prevalence of HTLV-1 infection was 5.1% (CI 95%: 4.2-6.0). In the multiple logistic regression model, HTLV-1 infection was associated with age ≥ 45 years, female sex, being first and second-generation Japanese immigrants, and having sexual partners with history of blood transfusion. The phylogenetic analysis revealed that all HTLV-1 were classified as Cosmopolitan (1a) subtype. Of them, 47.8% were classified as Transcontinental (A) subgroup and 52.2% as belonging to the Japanese (B) subgroup. Although most HTLV-1-infected patients were asymptomatic (97.3%), blurred vision was associated with HTLV-1 infection. The high prevalence of HTLV-1 infection found in this studied population and especially the intra- and interfamily HTLV-1 transmission presents an urgent call for preventive and control responses of this infection in Brazil

    High Prevalence of HTLV-1 Infection among Japanese Immigrants in Non-endemic Area of Brazil

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    <div><p>Background</p><p>Human T-lymphotropic virus type 1 (HTLV-1) has worldwide distribution and is considered endemic in many world regions, including southwestern Japan and Brazil. Japanese immigrants and their descendants have a high risk of acquiring this infection due to intense population exchange between Brazil and Japan.</p><p>Objective</p><p>This cross-sectional study aimed to estimate the prevalence of HTLV, analyze the main risk factors associated with this infection, identify the main circulating types and subtypes of HTLV in Japanese immigrants and descendants living in Campo Grande-MS (Middle-West Brazil), as well as analyze the phylogenetic relationship among isolates of HTLV.</p><p>Study Design</p><p>A total of 219 individuals were interviewed and submitted to blood collection. All collected blood samples were submitted for detection of anti-HTLV-1/2 using the immunoassay ELISA and confirmed by immunoblot method. The proviral DNA of the 14 samples HTLV- 1 positive were genotyped by nucleotide sequencing.</p><p>Results</p><p>The overall prevalence of HTLV-1 was 6.8% (IC 95%: 3,5-10,2). Descriptive analysis of behavioral risk factors showed statistical association between HTLV-1 and age greater than or equal to 45 years. The proviral DNA of HTLV-1 was detected in all HTLV-1 positive samples. Of these, 14 were sequenced and classified as Cosmopolitan subtype, and 50% (7/14) belonged to subgroup A (transcontinental) and 50% (7/14) to the subgroup B (Japanese).</p><p>Conclusion</p><p>The high prevalence of HTLV-1 found evidence of the importance of early diagnosis and counseling of individuals infected with HTLV-1 for the control and prevention of the spread of this infection among Japanese immigrants and their descendants in Central Brazil.</p></div
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