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1.
Eur J Clin Invest ; : e13421, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026101

RESUMO

As of October 2020, there are >1 million documented deaths with COVID-19. Excess deaths can be caused by both COVID-19 and the measures taken. COVID-19 shows extremely strong risk stratification across age, socioeconomic factors, and clinical factors. Calculation of years-of-life-lost from COVID-19 is methodologically challenging that can yield misleading over-estimates. Many early deaths may have been due to suboptimal management, malfunctional health systems, hydroxychloroquine, sending COVID-19 patients to nursing homes, and nosocomial infections; such deaths are partially avoidable moving forward. About 10% of the global population may be infected by October 2020. Global infection fatality rate is 0.15-0.20% (0.03-0.04% in those <70 years), with large variability across locations with different age-structure, institutionalization rates, socioeconomic inequalities, population-level clinical risk profile, public health measures, and health care. There is debate on whether at least 60% of the global population must be infected for herd immunity, or, conversely, mixing heterogeneity and pre-existing cross-immunity may allow substantially lower thresholds. Simulations are presented with a total of 1.58-8.76 million COVID-19 deaths over 5-years (1/2000-12/2024) globally (0.5-2.9% of total global deaths). The most favorable figures in that range would be feasible if high risk groups can be preferentially protected with lower infection rates than the remaining population. Death toll may also be further affected by potential availability of effective vaccines and treatments, optimal management and measures taken, COVID-19 interplay with influenza and other health problems, reinfection potential, and any chronic COVID-19 consequences. Targeted, precise management of the pandemic and avoiding past mistakes would help minimize mortality.

2.
Lancet Microbe ; 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33015652

RESUMO

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. The proportion of infected individuals who seroconvert is still an open question. In addition, it has been shown in some individuals that viral genome can be detected up to 3 months after symptom resolution. We investigated both seroconversion and PCR positivity in a large cohort of convalescent serum donors in the New York City (NY, USA) region. Methods: In this observational study, we ran an outreach programme in the New York City area. We recruited participants via the REDCap (Vanderbilt University, Nashville, TN, USA) online survey response. Individuals with confirmed or suspected SARS-CoV-2 infection were screened via PCR for presence of viral genome and via ELISA for presence of anti-SARS-CoV-2 spike antibodies. One-way ANOVA and Fisher's exact test were used to measure the association of age, gender, symptom duration, and days from symptom onset and resolution with positive antibody results. Findings: Between March 26 and April 10, 2020, we measured SARS-CoV-2 antibody titres in 1343 people. Of the 624 participants with confirmed SARS-CoV-2 infection who had serologies done after 4 weeks, all but three seroconverted to the SARS-CoV-2 spike protein, whereas 269 (37%) of 719 participants with suspected SARS-CoV-2 infection seroconverted. PCR positivity was detected up to 28 days from symptom resolution. Interpretation: Most patients with confirmed COVID-19 seroconvert, potentially providing immunity to reinfection. We also report that in a large proportion of individuals, viral genome can be detected via PCR in the upper respiratory tract for weeks after symptom resolution, but it is unclear whether this signal represents infectious virus. Analysis of our large cohort suggests that most patients with mild COVID-19 seroconvert 4 weeks after illness, and raises questions about the use of PCR to clear positive individuals. Funding: None.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33037944

RESUMO

Can a patient diagnosed with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) be infected again? This question is still unsolved. We tried to analyze local and literature cases with a positive respiratory swab after recovery. We collected data from symptomatic patients diagnosed with SARS-CoV-2 infection in the Italian Umbria Region that, after recovery, were again positive for SARS-CoV-2 in respiratory tract specimens. Samples were also assessed for infectivity in vitro. A systematic review of similar cases reported in the literature was performed. The study population was composed of 9 patients during a 4-month study period. Among the new positive samples, six were inoculated in Vero-E6 cells and showed no growth and negative molecular test in culture supernatants. All patients were positive for IgG against SARS-CoV-2 nucleoprotein and/or S protein. Conducting a review of the literature, 1350 similar cases have been found. The presumptive reactivation occurred in 34.5 days on average (standard deviation, SD, 18.7 days) after COVID-19 onset, when the 5.6% of patients presented fever and the 27.6% symptoms. The outcome was favorable in 96.7% of patients, while the 1.1% of them were still hospitalized at the time of data collection and the 2.1% died. Several hypotheses have been formulated to explain new positive respiratory samples after confirmed negativity. According to this study, the phenomenon seems to be due to the prolonged detection of SARS-CoV-2 RNA traces in respiratory samples of recovered patients. The failure of the virus to replicate in vitro suggests its inability to replicate in vivo.

6.
Science ; 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33055131

RESUMO

Reinfection, seasonality, and viral competition will shape endemic transmission patterns.

7.
Am J Case Rep ; 21: e927812, 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33009361

RESUMO

BACKGROUND This is a case report of an immunocompromised patient with a history of non-Hodgkin lymphoma and persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who was seronegative and successfully treated with convalescent plasma. CASE REPORT A 63-year-old woman with a past medical history of non-Hodgkin lymphoma in remission while on maintenance therapy with the anti-CD20 monoclonal antibody, obinutuzumab, tested positive for SARS-CoV-2 via nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) testing over 12 weeks and persistently tested seronegative for immunoglobulin G (IgG) antibodies using SARS-CoV-2 IgG chemiluminescent microparticle immunoassay technology. During this time, the patient experienced waxing and waning of symptoms, which included fever, myalgia, and non-productive cough, but never acquired severe respiratory distress. She was admitted to our hospital on illness day 88, and her symptoms resolved after the administration of convalescent plasma. CONCLUSIONS As the understanding of the pathogenesis of SARS-CoV-2 continues to evolve, we can currently only speculate about the occurrence of chronic infection vs. reinfection. The protective role of antibodies and their longevity against SARS-CoV-2 remain unclear. Since humoral immunity has an integral role in SARS-CoV-2 infection, various phase 3 vaccine trials are underway. In the context of this pandemic, the present case demonstrates the challenges in our understanding of testing and treating immunocompromised patients.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Hospedeiro Imunocomprometido , Linfoma não Hodgkin/imunologia , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Antineoplásicos Imunológicos/administração & dosagem , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/terapia , Feminino , Seguimentos , Humanos , Imunização Passiva/métodos , Linfoma não Hodgkin/complicações , Linfoma não Hodgkin/tratamento farmacológico , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase em Tempo Real/métodos , Testes Sorológicos/métodos , Índice de Gravidade de Doença , Resultado do Tratamento
8.
J Hematol Oncol ; 13(1): 131, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008453

RESUMO

SARS-CoV-2 has infected millions of people worldwide, but little is known at this time about second infections or reactivation. Here, we report a case of a 55-year-old female undergoing treatment for CD20+ B cell acute lymphoblastic leukemia who experienced a viral reactivation after receiving rituximab, cytarabine, and dasatinib. She was initially hospitalized with COVID-19 in April and developed a high antibody titer with two negative nasal polymerase chain reaction (PCR) swabs for SARS-CoV-2 on discharge. After recovery, she resumed treatment in June for her leukemia, which included rituximab, cytarabine, and dasatinib. She promptly lost her COVID-19 antibodies, and her nasal PCR turned positive in June. She developed a severe COVID-19 pneumonia with lymphopenia, high inflammatory markers, and characteristic bilateral ground-glass opacities on chest CT, requiring high-flow nasal cannula and transfer to the intensive care unit. She received steroids, anticoagulation, and convalescent plasma, and within 48 h she was off oxygen. She was discharged home in stable condition several days later. Given the short time frame from leukemia treatment to PCR positivity and the low case rate in mid-June in New York City, reinfection appears to have been unlikely and SARS-CoV-2 reactivation is a possible explanation. This case illustrates the risks of treating recently recovered COVID-19 patients with immunosuppressive therapy, particularly lymphocyte- and antibody-depleting therapy, and raises new questions about the potential of SARS-CoV-2 reactivation.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/imunologia , Citarabina/uso terapêutico , Imunossupressores/uso terapêutico , Pneumonia Viral/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Rituximab/uso terapêutico , Doença Aguda , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Anticoagulantes/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Citarabina/efeitos adversos , Feminino , Humanos , Imunização Passiva , Imunossupressores/efeitos adversos , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Recidiva , Rituximab/efeitos adversos , Esteroides/uso terapêutico , Resultado do Tratamento
9.
Artigo em Inglês | MEDLINE | ID: mdl-33052872

RESUMO

BACKGROUND: The novel coronavirus SARS-CoV-2, which causes the COVID-19 disease, has resulted in a global pandemic. Since its emergence in December 2019, the virus has infected millions of people, caused the deaths of hundreds of thousands and resulted in incalculable social and economic damage. Understanding the infectivity and transmission dynamics of the virus is essential for understanding how best to reduce mortality whilst ensuring minimal social restrictions to the lives of the general population. Anecdotal evidence is available, but detailed studies have not yet revealed whether infection with the virus results in immunity. OBJECTIVE: The objective of the study was to use mathematical modelling to investigate the reinfection frequency of COVID-19. METHODS: We have used the SIR (Susceptible, Infected, Recovered) framework and random processing based on empirical SARS-CoV-2 infection and fatality data from different regions to calculate the number of reinfections that would be expected to occur if no immunity to the disease occurred. RESULTS: Our model predicts that cases of reinfection should have been observed by now if primary SARS-CoV-2 infection did not protect from subsequent exposure in the short term, however, no such cases have been documented. CONCLUSIONS: This work concludes that infection with the SARS-CoV-2 virus provides short-term immunity to reinfection and therefore provides a useful insight for serological testing strategies, lockdown easing and vaccine design.

10.
medRxiv ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33052361

RESUMO

BACKGROUND: SARS-CoV-2-specific antibodies may protect from reinfection and disease, providing the rationale for administration of plasma containing SARS-CoV-2 neutralizing antibodies (nAb) as a treatment for COVID-19. The clinical factors and laboratory assays to streamline plasma donor selection, and the durability of nAb responses, are incompletely understood. METHODS: Adults with virologically-documented SARS-CoV-2 infection in a convalescent plasma donor screening program were tested for serum IgG to SARS-CoV-2 spike protein S1 domain, nucleoprotein (NP), and for nAb. RESULTS: Amongst 250 consecutive persons studied a median of 67 days since symptom onset, 243/250 (97%) were seropositive on one or more assays. Sixty percent of donors had nAb titers ≥1:80. Correlates of higher nAb titer included older age (adjusted OR [AOR] 1.03/year of age, 95% CI 1.00-1.06), male sex (AOR 2.08, 95% CI 1.13-3.82), fever during acute illness (AOR 2.73, 95% CI 1.25-5.97), and disease severity represented by hospitalization (AOR 6.59, 95% CI 1.32-32.96). Receiver operating characteristic (ROC) analyses of anti-S1 and anti-NP antibody results yielded cutoffs that corresponded well with nAb titers, with the anti-S1 assay being slightly more predictive. NAb titers declined in 37 of 41 paired specimens collected a median of 98 days (range, 77-120) apart (P<0.001). Seven individuals (2.8%) were persistently seronegative and lacked T cell responses. CONCLUSIONS: Nab titers correlated with COVID-19 severity, age, and sex. Standard commercially available SARS-CoV-2 IgG results can serve as useful surrogates for nAb testing. Functional nAb levels were found to decline and a small proportion of COVID-19 survivors lack adaptive immune responses.

11.
ACS Nano ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034449

RESUMO

Humanity is experiencing a catastrophic pandemic. SARS-CoV-2 has spread globally to cause significant morbidity and mortality, and there still remain unknowns about the biology and pathology of the virus. Even with testing, tracing, and social distancing, many countries are struggling to contain SARS-CoV-2. COVID-19 will only be suppressible when herd immunity develops, either because of an effective vaccine or if the population has been infected and is resistant to reinfection. There is virtually no chance of a return to pre-COVID-19 societal behavior until there is an effective vaccine. Concerted efforts by physicians, academic laboratories, and companies around the world have improved detection and treatment and made promising early steps, developing many vaccine candidates at a pace that has been unmatched for prior diseases. As of August 11, 2020, 28 of these companies have advanced into clinical trials with Moderna, CanSino, the University of Oxford, BioNTech, Sinovac, Sinopharm, Anhui Zhifei Longcom, Inovio, Novavax, Vaxine, Zydus Cadila, Institute of Medical Biology, and the Gamaleya Research Institute having moved beyond their initial safety and immunogenicity studies. This review analyzes these frontrunners in the vaccine development space and delves into their posted results while highlighting the role of the nanotechnologies applied by all the vaccine developers.

12.
Lancet Infect Dis ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058796
13.
Lancet Infect Dis ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058797

RESUMO

BACKGROUND: The degree of protective immunity conferred by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently unknown. As such, the possibility of reinfection with SARS-CoV-2 is not well understood. We describe an investigation of two instances of SARS-CoV-2 infection in the same individual. METHODS: A 25-year-old man who was a resident of Washoe County in the US state of Nevada presented to health authorities on two occasions with symptoms of viral infection, once at a community testing event in April, 2020, and a second time to primary care then hospital at the end of May and beginning of June, 2020. Nasopharyngeal swabs were obtained from the patient at each presentation and twice during follow-up. Nucleic acid amplification testing was done to confirm SARS-CoV-2 infection. We did next-generation sequencing of SARS-CoV-2 extracted from nasopharyngeal swabs. Sequence data were assessed by two different bioinformatic methodologies. A short tandem repeat marker was used for fragment analysis to confirm that samples from both infections came from the same individual. FINDINGS: The patient had two positive tests for SARS-CoV-2, the first on April 18, 2020, and the second on June 5, 2020, separated by two negative tests done during follow-up in May, 2020. Genomic analysis of SARS-CoV-2 showed genetically significant differences between each variant associated with each instance of infection. The second infection was symptomatically more severe than the first. INTERPRETATION: Genetic discordance of the two SARS-CoV-2 specimens was greater than could be accounted for by short-term in vivo evolution. These findings suggest that the patient was infected by SARS-CoV-2 on two separate occasions by a genetically distinct virus. Thus, previous exposure to SARS-CoV-2 might not guarantee total immunity in all cases. All individuals, whether previously diagnosed with COVID-19 or not, should take identical precautions to avoid infection with SARS-CoV-2. The implications of reinfections could be relevant for vaccine development and application. FUNDING: Nevada IDEA Network of Biomedical Research, and the National Institute of General Medical Sciences (National Institutes of Health).

16.
J Med Virol ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32897549

RESUMO

Coronavirus disease 2019 (COVID-19) reinfections could be a major aggravating factor in this current pandemic, as this would further complicate potential vaccine development and help to maintain worldwide virus pockets. To investigate this critical question, we conducted a clinical meta-analysis including all available currently reported cases of potential COVID-19 reinfections. We searched for all peer-reviewed articles in the search engine of the National Center for Biotechnology Information. While there are over 30,000 publications on COVID-19, only about 15 specifically target the subject of COVID-19 reinfections. Available patient data in these reports was analyzed for age, gender, time of reported relapse after initial infection and persistent COVID-19 positive polymerase chain reaction (PCR) results. Following the first episode of infection, cases of clinical relapse are reported at 34 (mean) ± 10.5 days after full recovery. Patients with clinical relapse have persisting positive COVID-19 PCR testing results until 39 ± 9 days following initial positive testing. For patients without clinical relapse, positive testing was reported up to 54 ± 24 days. There were no reports of any clinical reinfections after a 70-day period following initial infection.

17.
Rev Soc Bras Med Trop ; 53: e20200619, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32965458

RESUMO

With the large number of individuals infected and recovered from Covid-19, there is intense discussion about the quality and duration of the immunity elicited by SARS-CoV-2 infection, including the possibility of disease recurrence. Here we report a case with strong clinical, epidemiological and laboratorial evidence of, not only reinfection by SARS-CoV-2, but also clinical recurrence of Covid-19.


Assuntos
Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Recidiva , Anticorpos Antivirais/sangue , Betacoronavirus , Brasil , Feminino , Humanos , Pandemias , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
18.
PLoS Negl Trop Dis ; 14(8): e0008648, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866168

RESUMO

The phenomenon of COVID-19 patients tested positive for SARS-CoV-2 after discharge (redetectable as positive, RP) emerged globally. The data of incidence rate and risk factors for RP event and the clinical features of RP patients may provide recommendations for virus containment and cases management for COVID-19. We prospectively collected and analyzed the epidemiological, clinical and virological data from 285 adult patients with COVID-19 and acquired their definite clinical outcome (getting PCR positive or not during post-discharge surveillance). By March 10, 27 (9.5%) discharged patients had tested positive for SARS-CoV-2 in their nasopharyngeal swab after a median duration of 7·0 days (IQR 5·0-8·0). Compared to first admission, RP patients generally had milder clinical symptoms, lower viral load, shorter length of stay and improved pulmonary conditions at readmission (p<0.05). Elder RP patients (≥ 60 years old) were more likely to be symptomatic compared to younger patients (7/8, 87.5% vs. 3/19, 18.8%, p = 0.001) at readmission. Age, sex, epidemiological history, clinical symptoms and underlying diseases were similar between RP and non-RP patients (p>0.05). A prolonged duration of viral shedding (>10 days) during the first hospitalization [adjusted odds ratio [aOR]: 5.82, 95% confidence interval [CI]: 2.50-13.57 for N gene; aOR: 9.64, 95% CI: 3.91-23.73 for ORF gene] and higher Ct value (ORF) in the third week of the first hospitalization (aOR: 0.69; 95% CI: 0.50-0.95) were associated with RP events. In conclusion, RP events occurred in nearly 10% of COVID-19 patients shortly after the negative tests, were not associated with worsening symptoms and unlikely reflect reinfection. Patients' lack of efficiency in virus clearance was a risk factor for RP result. It is noteworthy that elder RP patients (≥ 60 years old) were more susceptible to clinical symptoms at readmission.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Feminino , Hospitalização , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pandemias , Alta do Paciente , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Estudos Prospectivos , Recidiva , Fatores de Risco , Eliminação de Partículas Virais , Adulto Jovem
19.
Am J Trop Med Hyg ; 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32888288

RESUMO

We describe six cases of healthcare professionals in Brazil who recovered but again presented symptoms consistent with COVID-19, with new positive reverse transcription (RT)-PCR test results. The cases reported herein presented symptom onset between March 16, 2020 and April 9, 2020. All were health professionals (four medical doctors), five were female, with a median age of 43.5 years, and three had comorbidities. All patients were confirmed for SARS-CoV-2 detection by RT-PCR in naso and/or oropharyngeal swab samples. Among the reported cases, three (50%) underwent RT-PCR testing in the period between the two symptomatic episodes, with negative results. The time elapsed between the onset of symptoms in the two episodes ranged from 53 to 70 days (median, 56.5 days). In the first episode, the main symptoms described were fever (4/6), myalgia (3/6), sore throat (3/6), and cough (3/6). Meanwhile, during the second episode, fever (4/6) and weakness (3/6) predominated. Most of the cases progressed without complications, although one individual presented hypoxemia (minimum SatO2 of 90%) in both episodes, and two, only in the second, one of which required intensive care unit admission, progressing with improvement after medication and receiving noninvasive ventilatory support. We report cases with recurrence of symptoms compatible with COVID-19, with positive RT-PCR results, that could represent the occurrence of viral reactivation or reinfection. The true nature of this phenomenon should be better clarified in future studies.

20.
Appl Math Model ; 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32952269

RESUMO

Most of the recent epidemic outbreaks in the world have as a trigger, a strong migratory component as has been evident in the recent Covid-19 pandemic. In this work we address the problem of migration of human populations and its effect on pathogen reinfections in the case of Dengue, using a Markov-chain susceptible-infected-susceptible (SIS) metapopulation model over a network. Our model postulates a general contact rate that represents a local measure of several factors: the population size of infected hosts that arrive at a given location as a function of total population size, the current incidence at neighboring locations, and the connectivity of the network where the disease spreads. This parameter can be interpreted as an indicator of outbreak risk at a given location. This parameter is tied to the fraction of individuals that move across boundaries (migration). To illustrate our model capabilities, we estimate from epidemic Dengue data in Mexico the dynamics of migration at a regional scale incorporating climate variability represented by an index based on precipitation data.

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