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1.
Clin Infect Dis ; 2021 Sep 21.
Article in English | MEDLINE | ID: covidwho-2017763

ABSTRACT

BACKGROUND: The public health impact of the COVID-19 pandemic has motivated a rapid search for potential therapeutics, with some key successes. However, the potential impact of different treatments, and consequently research and procurement priorities, have not been clear. METHODS: Using a mathematical model of SARS-CoV-2 transmission, COVID-19 disease and clinical care, we explore the public-health impact of different potential therapeutics, under a range of scenarios varying healthcare capacity, epidemic trajectories; and drug efficacy in the absence of supportive care. RESULTS: The impact of drugs like dexamethasone (delivered to the most critically-ill in hospital and whose therapeutic benefit is expected to depend on the availability of supportive care such as oxygen and mechanical ventilation) is likely to be limited in settings where healthcare capacity is lowest or where uncontrolled epidemics result in hospitals being overwhelmed. As such, it may avert 22% of deaths in high-income countries but only 8% in low-income countries (assuming R=1.35). Therapeutics for different patient populations (those not in hospital, early in the course of infection) and types of benefit (reducing disease severity or infectiousness, preventing hospitalisation) could have much greater benefits, particularly in resource-poor settings facing large epidemics. CONCLUSIONS: Advances in the treatment of COVID-19 to date have been focussed on hospitalised-patients and predicated on an assumption of adequate access to supportive care. Therapeutics delivered earlier in the course of infection that reduce the need for healthcare or reduce infectiousness could have significant impact, and research into their efficacy and means of delivery should be a priority.

2.
Commun Med (Lond) ; 2: 76, 2022.
Article in English | MEDLINE | ID: covidwho-1915298

ABSTRACT

Background: The emergence of the new SARS-CoV-2 Omicron variant, which is known to have a large number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination. Methods: Based on viral microneutralization assays, we evaluated in 90 individuals the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme. Results: Here we show that the percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 16.6% and 10%, respectively. After booster dose administration, the seroconvertion rate increased to 76.6%. The neutralization mean titer against Omicron in the CoronaVac protocol decreased over time, but after the booster dose, the mean titer increased 43.1 times. Conclusions: These results indicate a positive impact of this vaccine combination in the serological immune response against SARS-CoV-2 Omicron variant.

3.
Frontiers in immunology ; 13, 2022.
Article in English | EuropePMC | ID: covidwho-1904746

ABSTRACT

Background Effective and safe vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical to controlling the COVID-19 pandemic and will remain the most important tool in limiting the spread of the virus long after the pandemic is over. Methods We bring pioneering contributions on the maintenance of the immune response over a year on a real-life basis study in 1,587 individuals (18-90 yrs, median 39 yrs;1,208 female/379 male) who underwent vaccination with two doses of CoronaVac and BNT162b2 booster after 6-months of primary protocol. Findings Elevated levels of anti-spike IgG antibodies were detected after CoronaVac vaccination, which significantly decreased after 80 days and remained stable until the introduction of the booster dose. Heterologous booster restored antibody titers up to-1·7-fold, changing overall seropositivity to 96%. Titers of neutralising antibodies to the Omicron variant were lower in all timepoints than those against Delta variant. Individuals presenting neutralising antibodies against Omicron also presented the highest titers against Delta and anti-Spike IgG. Cellular immune response measurement pointed out a mixed immune profile with a robust release of chemokines, cytokines, and growth factors on the first month after CoronaVac vaccination followed by a gradual reduction over time and no increase after the booster dose. A stronger interaction between those mediators was noted over time. Prior exposure to the virus leaded to a more robust cellular immune response and a rise in antibody levels 60 days post CoronaVac than in individuals with no previous COVID-19. Both vaccines were safe and well tolerated among individuals. Interpretation Our data approach the effectiveness of CoronaVac association with BNT162b2 from the clinical and biological perspectives, aspects that have important implications for informing decisions about vaccine boosters. Funding Fiocruz, Brazil.

4.
J Med Virol ; 94(3): 1206-1211, 2022 03.
Article in English | MEDLINE | ID: covidwho-1718356

ABSTRACT

The Lambda variants of interest (VOI) (C37/GR/452Q.V1/21G) was initially reported in Lima, Peru but has gained rapid dissemination through other Latin American countries. Nevertheless, the dissemination and molecular epidemiology of the Lambda VOI in Brazil is unknown apart from a single case report. In this respect, we characterized the circulation of the SARS-CoV-2 Lambda VOI (C37/GR/452Q.V1/21G) in Sao Paulo State, Brazil. From March to June 2021, we identified seven Lambda isolates in a set of approximately 8000 newly sequenced genomes of the Network for Pandemic Alert of Emerging SARS-CoV-2 variants from Sao Paulo State. Interestingly, in three of the positive patients, the Lambda VOI infection was probably related to a contact transmission. These individuals were fully vaccinated to COVID-19 and presented mild symptoms. The remaining positive for Lambda VOI individuals showed different levels of COVID-19 symptoms and one of them needed hospitalization (score 5, WHO). In our study, we present a low level of Lambda VOI circulation in the Sao Paulo State. This reinforces the essential role of molecular surveillance for the effective SARS-CoV-2 pandemic response, especially in regard to circulating variants.


Subject(s)
COVID-19 , SARS-CoV-2 , Brazil/epidemiology , COVID-19/epidemiology , Humans , SARS-CoV-2/genetics , World Health Organization
6.
Front Public Health ; 9: 745310, 2021.
Article in English | MEDLINE | ID: covidwho-1477894

ABSTRACT

The emergence of several SARS-CoV-2 lineages presenting adaptive mutations is a matter of concern worldwide due to their potential ability to increase transmission and/or evade the immune response. While performing epidemiological and genomic surveillance of SARS-CoV-2 in samples from Porto Ferreira-São Paulo-Brazil, we identified sequences classified by pangolin as B.1.1.28 harboring Spike L452R mutation, in the RBD region. Phylogenetic analysis revealed that these sequences grouped into a monophyletic branch, with others from Brazil, mainly from the state of São Paulo. The sequences had a set of 15 clade defining amino acid mutations, of which six were in the Spike protein. A new lineage was proposed to Pango and it was accepted and designated P.4. In samples from the city of Porto Ferreira, P.4 lineage has been increasing in frequency since it was first detected in March 2021, corresponding to 34.7% of the samples sequenced in June, the second in prevalence after P.1. Also, it is circulating in 30 cities from the state of São Paulo, and it was also detected in one sample from the state of Sergipe and two from the state of Rio de Janeiro. Further studies are needed to understand whether P.4 should be considered a new threat.


Subject(s)
COVID-19 , SARS-CoV-2 , Brazil , Humans , Mutation , Phylogeny , Spike Glycoprotein, Coronavirus/genetics
7.
Ecancermedicalscience ; 15: 1269, 2021.
Article in English | MEDLINE | ID: covidwho-1354826

ABSTRACT

BACKGROUND: The coronavirus disease (COVID-19) pandemic has had enormous consequences in Brazil and worldwide. Patients with cancer affected by COVID-19 are at a higher risk of developing complications and worse outcomes compared to the non-cancer population, particularly the ones on active systemic treatment. Considering the COVID-19's high transmissibility in asymptomatic and pre-symptomatic patients, we sought to determine the prevalence of COVID-19 infection in patients with solid cancers receiving systemic therapy in a Brazilian public health hospital. Furthermore, we studied whether socio-economic status was associated with prevalence. METHODS: Consecutive asymptomatic patients undergoing treatment for solid tumours at the chemotherapy and infusion centre of Hospital de Base were enrolled. Patients were prospectively tested for severe acute respiratory syndrome coronavirus 2 RNA real-time polymerase chain reaction with nasal and oropharyngeal swabs immediately prior to treatment. A socio-economic survey was carried out prior to testing. Demographic and socio-economic characteristics were summarised in means, medians and proportions. RESULTS: From 6 to 13 October 2020, 148 asymptomatic patients were identified. Of those, 41 were excluded, leaving 107 eligible patients. The mean age of the population was 58 years (SD ± 12.6); 54% were female and 90% were self-identified as White. The most common cancer sites were gastrointestinal tract (36%) and breast (25%). Most patients had a metastatic disease (59%) and were on anticancer treatment involving chemotherapy (95%). Regarding socio-economic status, 46% of our population had either primary school or illiterate as their highest educational level. In terms of monthly income, 92% had a personal income inferior to U$380 and 88% a household income inferior to U$585. Of the 107 patients tested, only 1 (0.9%) was positive for COVID-19. This is a 48-year-old man living in an urban area, with primary school educational level and a monthly personal income inferior to U$390. CONCLUSION: Despite a high prevalence of COVID-19 in Brazil, our cohort demonstrated a low prevalence of COVID-19 (0.9%) amongst asymptomatic patients with cancer. We hypothesise that patients with cancer, independent of their socio-economic status, are aware of the increased risk of developing a severe disease and are adherent to physical distancing, masking and hygiene measures.

8.
Viruses ; 13(7)2021 06 26.
Article in English | MEDLINE | ID: covidwho-1289023

ABSTRACT

The rapid development of efficacious and safe vaccines against coronavirus disease 2019 (COVID-19) has been instrumental in mitigating the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Moreover, the emergence of SARS-CoV-2 variants raised concerns on the efficacy of these vaccines. Herein, we report two cases of breakthrough infections with the P1 variant in patients vaccinated with CoronaVac, which is one of the two vaccines authorized for emergency use in the Brazilian immunization program. Our observations suggest that the vaccine reduced the severity of the disease and highlight the potential risk of illness following vaccination and subsequent infection with the P1 variant as well as for continued efforts to prevent and diagnose infection in vaccinated persons.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19/diagnostic imaging , COVID-19/immunology , SARS-CoV-2/immunology , Vaccination/adverse effects , Brazil , COVID-19/drug therapy , COVID-19/prevention & control , COVID-19 Nucleic Acid Testing , COVID-19 Vaccines/administration & dosage , Clinical Trials as Topic , Dexamethasone/therapeutic use , Humans , Male , Middle Aged , SARS-CoV-2/genetics , Severity of Illness Index , Tomography, X-Ray Computed , Treatment Outcome , Vaccination/statistics & numerical data
9.
J Med Virol ; 93(3): 1770-1775, 2021 03.
Article in English | MEDLINE | ID: covidwho-1196472

ABSTRACT

Herein, we report a case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and dengue coinfection, presented as a fatal stroke in our hospital, in São José do Rio Preto, São Paulo State, a Brazilian city hyperendemic for dengue viruses and other arthropod-borne viruses (arboviruses) and currently facing a surge of SARS-CoV-2 cases. This case is the first described in the literature and contributes to the better understanding of clinical presentations of two important diseases in a tropical setting.


Subject(s)
COVID-19/complications , Coinfection/complications , Dengue Virus/pathogenicity , Dengue/complications , SARS-CoV-2/pathogenicity , Stroke/etiology , Stroke/virology , Arboviruses/pathogenicity , Brazil , COVID-19/virology , Coinfection/virology , Dengue/virology , Female , Humans , Middle Aged
10.
Nat Hum Behav ; 4(8): 856-865, 2020 08.
Article in English | MEDLINE | ID: covidwho-690410

ABSTRACT

The first case of COVID-19 was detected in Brazil on 25 February 2020. We report and contextualize epidemiological, demographic and clinical findings for COVID-19 cases during the first 3 months of the epidemic. By 31 May 2020, 514,200 COVID-19 cases, including 29,314 deaths, had been reported in 75.3% (4,196 of 5,570) of municipalities across all five administrative regions of Brazil. The R0 value for Brazil was estimated at 3.1 (95% Bayesian credible interval = 2.4-5.5), with a higher median but overlapping credible intervals compared with some other seriously affected countries. A positive association between higher per-capita income and COVID-19 diagnosis was identified. Furthermore, the severe acute respiratory infection cases with unknown aetiology were associated with lower per-capita income. Co-circulation of six respiratory viruses was detected but at very low levels. These findings provide a comprehensive description of the ongoing COVID-19 epidemic in Brazil and may help to guide subsequent measures to control virus transmission.


Subject(s)
Betacoronavirus/isolation & purification , Coronavirus Infections , Disease Transmission, Infectious , Influenza, Human , Pandemics , Pneumonia, Viral , Adult , Aged , Brazil/epidemiology , COVID-19 , COVID-19 Testing , Child , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/statistics & numerical data , Coinfection/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/drug therapy , Coronavirus Infections/mortality , Coronavirus Infections/therapy , Coronavirus Infections/transmission , Disease Transmission, Infectious/prevention & control , Disease Transmission, Infectious/statistics & numerical data , Female , Hospitalization/statistics & numerical data , Humans , Infant , Influenza, Human/diagnosis , Influenza, Human/epidemiology , Influenza, Human/virology , Male , Mortality , Pneumonia, Viral/diagnosis , Pneumonia, Viral/mortality , Pneumonia, Viral/therapy , Pneumonia, Viral/transmission , SARS-CoV-2 , Socioeconomic Factors
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