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1.
J Infect Dis ; 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: covidwho-2269169

RESUMEN

BACKGROUND: The impact variant-specific immune evasion and waning protection have on declining COVID-19 vaccine effectiveness remains unclear. Using whole-genome-sequencing (WGS), we examined the contribution of these factors on the decline observed following the introduction of the Delta variant. Further, we evaluated the utility of calendar-period-based classification as an alternative to WGS. METHODS: We conducted a test-negative-case-control study among people who received SARS-CoV-2 RT-PCR testing in the Yale New Haven Health System between April 1 and August 24, 2021. Variant classification was performed using WGS and calendar-period. RESULTS: Overall, 2,029 cases (RT-PCR positive, sequenced samples [infections]) and 343,985 controls (negative RT-PCRs) were included. VE 14-89 days after 2nd dose was significantly higher against WGS-classified Alpha-infection (84.4%, CI: 75.6-90.0%) than Delta-infection (68.9%, CI: 58.0-77.1%, p-value = 0.013). The odds of WGS-classified Delta-infection were significantly higher 90-149 than 14-89 days after 2nd dose (p-value = 0.003). VE estimates against calendar-period-classified infections approximated estimates against WGS-classified infections, however, calendar-period-based classification was subject to outcome misclassification (35%: Alpha-period, 4%: Delta-period). CONCLUSIONS: Both waning protection and variant-specific immune evasion contributed to the lower effectiveness. While VE estimates against calendar-period-classified infections mirrored those against WGS-classified infections, our analysis highlights the need for WGS when variants are co-circulating and misclassification is likely.

2.
Sci Rep ; 12(1): 22175, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: covidwho-2186046

RESUMEN

Sero-surveillance can monitor and project disease burden and risk. However, SARS-CoV-2 antibody test results can produce false positive results, limiting their efficacy as a sero-surveillance tool. False positive SARS-CoV-2 antibody results are associated with malaria exposure, and understanding this association is essential to interpret sero-surveillance results from malaria-endemic countries. Here, pre-pandemic samples from eight malaria endemic and non-endemic countries and four continents were tested by ELISA to measure SARS-CoV-2 Spike S1 subunit reactivity. Individuals with acute malaria infection generated substantial SARS-CoV-2 reactivity. Cross-reactivity was not associated with reactivity to other human coronaviruses or other SARS-CoV-2 proteins, as measured by peptide and protein arrays. ELISAs with deglycosylated and desialated Spike S1 subunits revealed that cross-reactive antibodies target sialic acid on N-linked glycans of the Spike protein. The functional activity of cross-reactive antibodies measured by neutralization assays showed that cross-reactive antibodies did not neutralize SARS-CoV-2 in vitro. Since routine use of glycosylated or sialated assays could result in false positive SARS-CoV-2 antibody results in malaria endemic regions, which could overestimate exposure and population-level immunity, we explored methods to increase specificity by reducing cross-reactivity. Overestimating population-level exposure to SARS-CoV-2 could lead to underestimates of risk of continued COVID-19 transmission in sub-Saharan Africa.


Asunto(s)
COVID-19 , Malaria , Humanos , Glicoproteína de la Espiga del Coronavirus , SARS-CoV-2 , Anticuerpos Antivirales , Reacciones Cruzadas , Ácido N-Acetilneuramínico , Epítopos
3.
PLoS Med ; 19(9): e1004093, 2022 09.
Artículo en Inglés | MEDLINE | ID: covidwho-2021514

RESUMEN

BACKGROUND: The structural environment of urban slums, including physical, demographic, and socioeconomic attributes, renders inhabitants more vulnerable to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Yet, little is known about the specific determinants that contribute to high transmission within these communities. We therefore aimed to investigate SARS-CoV-2 seroprevalence in an urban slum in Brazil. METHODS AND FINDINGS: We performed a cross-sectional serosurvey of an established cohort of 2,041 urban slum residents from the city of Salvador, Brazil between November 2020 and February 2021, following the first Coronavirus Disease 2019 (COVID-19) pandemic wave in the country and during the onset of the second wave. The median age in this population was 29 years (interquartile range [IQR] 16 to 44); most participants reported their ethnicity as Black (51.5%) or Brown (41.7%), and 58.5% were female. The median size of participating households was 3 (IQR 2 to 4), with a median daily per capita income of 2.32 (IQR 0.33-5.15) US Dollars. The main outcome measure was presence of IgG against the SARS-CoV-2 spike protein. We implemented multilevel models with random intercepts for each household to estimate seroprevalence and associated risk factors, adjusting for the sensitivity and specificity of the assay, and the age and gender distribution of our study population. We identified high seroprevalence (47.9%, 95% confidence interval [CI] 44.2% to 52.1%), particularly among female residents (50.3% [95% CI 46.3% to 54.8%] versus 44.6% [95% CI 40.1% to 49.4%] among male residents, p < 0.01) and among children (54.4% [95% CI 49.6% to 59.3%] versus 45.4% [95% CI 41.5% to 49.7%] among adults, p < 0.01). Adults residing in households with children were more likely to be seropositive (48.6% [95% CI 44.8% to 52.3%] versus 40.7% [95% CI 37.2% to 44.3%], p < 0.01). Women who were unemployed and living below the poverty threshold (daily per capita household income <$1.25) were more likely to be seropositive compared to men with the same employment and income status (53.9% [95% CI 47.0% to 60.6%] versus 32.9% [95% CI 23.2% to 44.3%], p < 0.01). Participation in the study was voluntary, which may limit the generalizability of our findings. CONCLUSIONS: Prior to the peak of the second wave of the COVID-19 pandemic, cumulative incidence as assessed by serology approached 50% in a Brazilian urban slum population. In contrast to observations from industrialized countries, SARS-CoV-2 incidence was highest among children, as well as women living in extreme poverty. These findings emphasize the need for targeted interventions that provide safe environments for children and mitigate the structural risks posed by crowding and poverty for the most vulnerable residents of urban slum communities.


Asunto(s)
COVID-19 , Adulto , Brasil/epidemiología , COVID-19/epidemiología , Niño , Estudios Transversales , Femenino , Humanos , Inmunoglobulina G , Masculino , Pandemias , Áreas de Pobreza , SARS-CoV-2 , Estudios Seroepidemiológicos , Glicoproteína de la Espiga del Coronavirus
4.
PLoS Biol ; 20(5): e3001506, 2022 05.
Artículo en Inglés | MEDLINE | ID: covidwho-1862232

RESUMEN

The impact of Coronavirus Disease 2019 (COVID-19) mRNA vaccination on pregnancy and fertility has become a major topic of public interest. We investigated 2 of the most widely propagated claims to determine (1) whether COVID-19 mRNA vaccination of mice during early pregnancy is associated with an increased incidence of birth defects or growth abnormalities; and (2) whether COVID-19 mRNA-vaccinated human volunteers exhibit elevated levels of antibodies to the human placental protein syncytin-1. Using a mouse model, we found that intramuscular COVID-19 mRNA vaccination during early pregnancy at gestational age E7.5 did not lead to differences in fetal size by crown-rump length or weight at term, nor did we observe any gross birth defects. In contrast, injection of the TLR3 agonist and double-stranded RNA mimic polyinosinic-polycytidylic acid, or poly(I:C), impacted growth in utero leading to reduced fetal size. No overt maternal illness following either vaccination or poly(I:C) exposure was observed. We also found that term fetuses from these murine pregnancies vaccinated prior to the formation of the definitive placenta exhibit high circulating levels of anti-spike and anti-receptor-binding domain (anti-RBD) antibodies to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) consistent with maternal antibody status, indicating transplacental transfer in the later stages of pregnancy after early immunization. Finally, we did not detect increased levels of circulating anti-syncytin-1 antibodies in a cohort of COVID-19 vaccinated adults compared to unvaccinated adults by ELISA. Our findings contradict popular claims associating COVID-19 mRNA vaccination with infertility and adverse neonatal outcomes.


Asunto(s)
COVID-19 , Animales , Anticuerpos Antivirales , COVID-19/prevención & control , Femenino , Feto , Productos del Gen env , Humanos , Ratones , Placenta/metabolismo , Embarazo , Proteínas Gestacionales , ARN Mensajero/genética , ARN Mensajero/metabolismo , SARS-CoV-2 , Vacunación
5.
J Infect Dis ; 225(3): 374-384, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: covidwho-1672205

RESUMEN

BACKGROUND: The underlying immunologic deficiencies enabling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection are currently unknown. We describe deep longitudinal immune profiling of a transplant recipient hospitalized twice for coronavirus disease 2019 (COVID-19). METHODS: A 66-year-old male renal transplant recipient was hospitalized with COVID-19 March 2020 then readmitted to the hospital with COVID-19 233 days after initial diagnosis. Virologic and immunologic investigations were performed on samples from the primary and secondary infections. RESULTS: Whole viral genome sequencing and phylogenetic analysis revealed that viruses causing both infections were caused by distinct genetic lineages without evidence of immune escape mutations. Longitudinal comparison of cellular and humoral responses during primary SARS-CoV-2 infection revealed that this patient responded to the primary infection with low neutralization titer anti-SARS-CoV-2 antibodies that were likely present at the time of reinfection. CONCLUSIONS: The development of neutralizing antibodies and humoral memory responses in this patient failed to confer protection against reinfection, suggesting that they were below a neutralizing titer threshold or that additional factors may be required for efficient prevention of SARS-CoV-2 reinfection. Development of poorly neutralizing antibodies may have been due to profound and relatively specific reduction in naive CD4 T-cell pools. Seropositivity alone may not be a perfect correlate of protection in immunocompromised patients.


Asunto(s)
COVID-19 , Reinfección , Receptores de Trasplantes , Anciano , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Humanos , Masculino , Trasplante de Órganos , Filogenia , Reinfección/inmunología , Reinfección/virología , SARS-CoV-2/genética
6.
Open forum infectious diseases ; 8(Suppl 1):S257-S257, 2021.
Artículo en Inglés | EuropePMC | ID: covidwho-1564986

RESUMEN

Background Streptococcus pneumoniae (pneumococcus) is a common colonizer of the upper respiratory tract and can progress to cause invasive and mucosal disease. Additionally, infection with pneumococcus can complicate respiratory viral infections (influenza, respiratory syncytial virus, etc.) by exacerbating the initial disease. Limited data exist describing the potential relationship of SARS-CoV-2 infection with pneumococcus and the role of co-infection in influencing COVID-19 severity. Methods Inpatients and healthcare workers testing positive for SARS-CoV-2 during March-August 2020 were tested for pneumococcus through culture-enrichment of saliva followed by RT-qPCR (to identify carriage) and for inpatients only, serotype-specific urine antigen detection (UAD) assays (to identify pneumococcal pneumonia). A multinomial multivariate regression model was used to examine the relationship between pneumococcal detection and COVID-19 severity. Results Among the 126 subjects who tested positive for SARS-CoV-2, the median age was 62 years;54.9% of subjects were male;88.89% were inpatients;23.5% had an ICU stay;and 13.5% died. Pneumococcus was detected in 17 subjects (13.5%) by any method, including 5 subjects (4.0%) by RT-qPCR and 12 subjects (13.6%) by UAD. Little to no bacterial growth was observed on 21/235 culture plates. Detection by UAD was associated with both moderate and severe COVID-19 disease while RT-qPCR detection in saliva was not associated with severity. None of the 12 individuals who were UAD-positive died. Conclusion Pneumococcal pneumonia (as determined by UAD) continues to occur during the ongoing pandemic and may be associated with more serious COVID-19 outcomes. Detection of pneumococcal carriage may be masked by high levels of antibiotic use. Future studies should better characterize the relationship between pneumococcus and SARS-CoV-2 across all disease severity levels. Disclosures Akiko Iwasaki, PhD, 4Bio (Consultant, Advisor or Review Panel member)Adaptive Biotechnologies (Consultant, Advisor or Review Panel member)Blavatnik (Grant/Research Support)HHMI (Grant/Research Support)Mathers (Grant/Research Support)NIH (Grant/Research Support)Spring Discovery (Grant/Research Support)Spring Discovery (Consultant, Advisor or Review Panel member)Vedanta InProTher (Consultant, Advisor or Review Panel member)Yale School of Medicine (Grant/Research Support) Nathan D. Grubaugh, PhD, Tempus Labs (Consultant) Ronika Alexander-Parrish, RN, MAEd, Pfizer (Employee, Shareholder) Adriano Arguedas, MD, Pfizer (Employee) Bradford D. Gessner, MD, MPH, Pfizer Inc. (Employee) Daniel Weinberger, PhD, Affinivax (Consultant)Merck (Consultant, Grant/Research Support)Pfizer (Consultant, Grant/Research Support) Anne Wyllie, PhD, Global Diagnostic Systems (Consultant)Pfizer (Advisor or Review Panel member, Research Grant or Support)PPS Health (Consultant)Tempus Labs, Inc (Research Grant or Support)

7.
Nature ; 600(7889): 523-529, 2021 12.
Artículo en Inglés | MEDLINE | ID: covidwho-1462014

RESUMEN

The emergence of SARS-CoV-2 variants with mutations in major neutralizing antibody-binding sites can affect humoral immunity induced by infection or vaccination1-6. Here we analysed the development of anti-SARS-CoV-2 antibody and T cell responses in individuals who were previously infected (recovered) or uninfected (naive) and received mRNA vaccines to SARS-CoV-2. While individuals who were previously infected sustained higher antibody titres than individuals who were uninfected post-vaccination, the latter reached comparable levels of neutralization responses to the ancestral strain after the second vaccine dose. T cell activation markers measured upon spike or nucleocapsid peptide in vitro stimulation showed a progressive increase after vaccination. Comprehensive analysis of plasma neutralization using 16 authentic isolates of distinct locally circulating SARS-CoV-2 variants revealed a range of reduction in the neutralization capacity associated with specific mutations in the spike gene: lineages with E484K and N501Y/T (for example, B.1.351 and P.1) had the greatest reduction, followed by lineages with L452R (for example, B.1.617.2). While both groups retained neutralization capacity against all variants, plasma from individuals who were previously infected and vaccinated displayed overall better neutralization capacity than plasma from individuals who were uninfected and also received two vaccine doses, pointing to vaccine boosters as a relevant future strategy to alleviate the effect of emerging variants on antibody neutralizing activity.


Asunto(s)
Anticuerpos Antivirales/inmunología , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/inmunología , Linfocitos T/inmunología , Vacunas Sintéticas/inmunología , Vacunas de ARNm/inmunología , Vacuna nCoV-2019 mRNA-1273/inmunología , Adulto , Anciano , Anticuerpos Neutralizantes/inmunología , Vacuna BNT162/inmunología , Femenino , Personal de Salud/estadística & datos numéricos , Humanos , Inmunidad Humoral , Masculino , Persona de Mediana Edad , Mutación , Estudios Retrospectivos , SARS-CoV-2/clasificación , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología
8.
Res Sq ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: covidwho-1389924

RESUMEN

The underlying immunologic deficiencies enabling SARS-CoV-2 reinfections are currently unknown. Here we describe a renal-transplant recipient who developed recurrent, symptomatic SARS-CoV-2 infection 7 months after primary infection. To elucidate the immunological mechanisms responsible for reinfection, we performed longitudinal profiling of cellular and humoral responses during both primary and recurrent SARS-CoV-2 infection. We found that the patient responded to the primary infection with transient, poor-quality adaptive immune responses that was further compromised by intervening treatment for acute rejection of the renal allograft prior to reinfection. Importantly, we identified the development of neutralizing antibodies and humoral memory responses prior to SARS-CoV-2 reinfection. However, these neutralizing antibodies failed to confer protection against reinfection, suggesting that additional factors are required for efficient prevention of SARS-CoV-2 reinfection. Further, we found no evidence supporting viral evasion of primary adaptive immune responses, suggesting that susceptibility to reinfection may be determined by host factors rather than pathogen adaptation.

9.
Sci Signal ; 14(690)2021 07 06.
Artículo en Inglés | MEDLINE | ID: covidwho-1299216

RESUMEN

Coronavirus disease 2019 (COVID-19) has poorer clinical outcomes in males than in females, and immune responses underlie these sex-related differences. Because immune responses are, in part, regulated by metabolites, we examined the serum metabolomes of COVID-19 patients. In male patients, kynurenic acid (KA) and a high KA-to-kynurenine (K) ratio (KA:K) positively correlated with age and with inflammatory cytokines and chemokines and negatively correlated with T cell responses. Males that clinically deteriorated had a higher KA:K than those that stabilized. KA inhibits glutamate release, and glutamate abundance was lower in patients that clinically deteriorated and correlated with immune responses. Analysis of data from the Genotype-Tissue Expression (GTEx) project revealed that the expression of the gene encoding the enzyme that produces KA, kynurenine aminotransferase, correlated with cytokine abundance and activation of immune responses in older males. This study reveals that KA has a sex-specific link to immune responses and clinical outcomes in COVID-19, suggesting a positive feedback between metabolites and immune responses in males.


Asunto(s)
COVID-19/inmunología , Ácido Quinurénico/inmunología , SARS-CoV-2 , Adulto , Anciano , COVID-19/sangre , Estudios de Casos y Controles , Síndrome de Liberación de Citoquinas/sangre , Síndrome de Liberación de Citoquinas/etiología , Síndrome de Liberación de Citoquinas/inmunología , Citocinas/sangre , Citocinas/inmunología , Femenino , Humanos , Ácido Quinurénico/sangre , Modelos Logísticos , Masculino , Redes y Vías Metabólicas/inmunología , Metabolómica , Persona de Mediana Edad , Análisis Multivariante , Índice de Severidad de la Enfermedad , Factores Sexuales , Transducción de Señal/inmunología , Triptófano/metabolismo
11.
Med (N Y) ; 2(3): 263-280.e6, 2021 03 12.
Artículo en Inglés | MEDLINE | ID: covidwho-1284368

RESUMEN

BACKGROUND: Scaling SARS-CoV-2 testing to meet demands of safe reopenings continues to be plagued by assay costs and supply chain shortages. In response, we developed SalivaDirect, which received Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration (FDA). METHODS: We simplified our saliva-based diagnostic test by (1) not requiring collection tubes with preservatives, (2) replacing nucleic acid extraction with a simple enzymatic and heating step, and (3) testing specimens with a dualplex qRT-PCR assay. Moreover, we validated SalivaDirect with reagents and instruments from multiple vendors to minimize supply chain issues. FINDINGS: From our hospital cohort, we show a high positive agreement (94%) between saliva tested with SalivaDirect and nasopharyngeal swabs tested with a commercial qRT-PCR kit. In partnership with the National Basketball Association (NBA) and National Basketball Players Association (NBPA), we tested 3,779 saliva specimens from healthy individuals and detected low rates of invalid (0.3%) and false-positive (<0.05%) results. CONCLUSIONS: We demonstrate that saliva is a valid alternative to swabs for SARS-CoV-2 screening and that SalivaDirect can make large-scale testing more accessible and affordable. Uniquely, we can designate other laboratories to use our sensitive, flexible, and simplified platform under our EUA (https://publichealth.yale.edu/salivadirect/). FUNDING: This study was funded by the NBA and NBPA (N.D.G.), the Huffman Family Donor Advised Fund (N.D.G.), a Fast Grant from Emergent Ventures at the Mercatus Center at George Mason University (N.D.G.), the Yale Institute for Global Health (N.D.G.), and the Beatrice Kleinberg Neuwirth Fund (A.I.K.). C.B.F.V. is supported by NWO Rubicon 019.181EN.004.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Prueba de COVID-19 , Humanos , Laboratorios , SARS-CoV-2/genética , Saliva
12.
Med (N Y) ; 2(5): 591-610.e10, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: covidwho-1220962

RESUMEN

BACKGROUND: Pregnant women are at increased risk for severe outcomes from coronavirus disease 2019 (COVID-19), but the pathophysiology underlying this increased morbidity and its potential effect on the developing fetus is not well understood. METHODS: We assessed placental histology, ACE2 expression, and viral and immune dynamics at the term placenta in pregnant women with and without respiratory severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. FINDINGS: The majority (13 of 15) of placentas analyzed had no detectable viral RNA. ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term, suggesting that low ACE2 expression may protect the term placenta from viral infection. Using immortalized cell lines and primary isolated placental cells, we found that cytotrophoblasts, the trophoblast stem cells and precursors to syncytiotrophoblasts, rather than syncytiotrophoblasts or Hofbauer cells, are most vulnerable to SARS-CoV-2 infection in vitro. To better understand potential immune mechanisms shielding placental cells from infection in vivo, we performed bulk and single-cell transcriptomics analyses and found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited robust immune responses, including increased activation of natural killer (NK) and T cells, increased expression of interferon-related genes, as well as markers associated with pregnancy complications such as preeclampsia. CONCLUSIONS: SARS-CoV-2 infection in late pregnancy is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion. FUNDING: NIH (T32GM007205, F30HD093350, K23MH118999, R01AI157488, U01DA040588) and Fast Grant funding support from Emergent Ventures at the Mercatus Center.


Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , Enzima Convertidora de Angiotensina 2/genética , Femenino , Humanos , Placenta/metabolismo , Embarazo , Complicaciones Infecciosas del Embarazo/metabolismo , SARS-CoV-2
13.
Nat Med ; 27(7): 1178-1186, 2021 07.
Artículo en Inglés | MEDLINE | ID: covidwho-1217708

RESUMEN

Recent studies have provided insights into innate and adaptive immune dynamics in coronavirus disease 2019 (COVID-19). However, the exact features of antibody responses that govern COVID-19 disease outcomes remain unclear. In this study, we analyzed humoral immune responses in 229 patients with asymptomatic, mild, moderate and severe COVID-19 over time to probe the nature of antibody responses in disease severity and mortality. We observed a correlation between anti-spike (S) immunoglobulin G (IgG) levels, length of hospitalization and clinical parameters associated with worse clinical progression. Although high anti-S IgG levels correlated with worse disease severity, such correlation was time dependent. Deceased patients did not have higher overall humoral response than discharged patients. However, they mounted a robust, yet delayed, response, measured by anti-S, anti-receptor-binding domain IgG and neutralizing antibody (NAb) levels compared to survivors. Delayed seroconversion kinetics correlated with impaired viral control in deceased patients. Finally, although sera from 85% of patients displayed some neutralization capacity during their disease course, NAb generation before 14 d of disease onset emerged as a key factor for recovery. These data indicate that COVID-19 mortality does not correlate with the cross-sectional antiviral antibody levels per se but, rather, with the delayed kinetics of NAb production.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Inmunoglobulina G/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anciano , Anciano de 80 o más Años , COVID-19/mortalidad , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Portador Sano/inmunología , Femenino , Humanos , Inmunidad Humoral , Cinética , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , SARS-CoV-2/inmunología , Índice de Severidad de la Enfermedad , Factores de Tiempo
14.
Emerg Infect Dis ; 27(4): 1146-1150, 2021 04.
Artículo en Inglés | MEDLINE | ID: covidwho-1147295

RESUMEN

The expense of saliva collection devices designed to stabilize severe acute respiratory syndrome coronavirus 2 RNA is prohibitive to mass testing. However, virus RNA in nonsupplemented saliva is stable for extended periods and at elevated temperatures. Simple plastic tubes for saliva collection will make large-scale testing and continued surveillance easier.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19 , ARN Viral , SARS-CoV-2 , Saliva/virología , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/virología , Creación de Capacidad/métodos , Humanos , Estabilidad del ARN , ARN Viral/aislamiento & purificación , ARN Viral/fisiología , Reproducibilidad de los Resultados , Asignación de Recursos , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Manejo de Especímenes/economía , Manejo de Especímenes/instrumentación , Manejo de Especímenes/métodos
15.
PLoS One ; 16(3): e0248025, 2021.
Artículo en Inglés | MEDLINE | ID: covidwho-1115309

RESUMEN

INTRODUCTION: Healthcare workers (HCW) treating COVID-19 patients are at high risk for infection and may also spread infection through their contact with vulnerable patients. Smell loss has been associated with SARS-CoV-2 infection, but it is unknown whether monitoring for smell loss can be used to identify asymptomatic infection among high risk individuals. In this study we sought to determine if tracking smell sensitivity and loss using an at-home assessment could identify SARS-CoV-2 infection in HCW. METHODS AND FINDINGS: We performed a prospective cohort study tracking 473 HCW across three months to determine if smell loss could predict SARS-CoV-2 infection in this high-risk group. HCW subjects completed a longitudinal, behavioral at-home assessment of olfaction with household items, as well as detailed symptom surveys that included a parosmia screening questionnaire, and real-time quantitative polymerase chain reaction testing to identify SARS-CoV-2 infection. Our main measures were the prevalence of smell loss in SARS-CoV-2-positive HCW versus SARS-CoV-2-negative HCW, and timing of smell loss relative to SARS-CoV-2 test positivity. SARS-CoV-2 was identified in 17 (3.6%) of 473 HCW. HCW with SARS-CoV-2 infection were more likely to report smell loss than SARS-CoV-2-negative HCW on both the at-home assessment and the screening questionnaire (9/17, 53% vs 105/456, 23%, P < .01). 6/9 (67%) of SARS-CoV-2-positive HCW reporting smell loss reported smell loss prior to having a positive SARS-CoV-2 test, and smell loss was reported a median of two days before testing positive. Neurological symptoms were reported more frequently among SARS-CoV-2-positive HCW who reported smell loss compared to those without smell loss (9/9, 100% vs 3/8, 38%, P < .01). CONCLUSIONS: In this prospective study of HCW, self-reported changes in smell using two different measures were predictive of SARS-CoV-2 infection. Smell loss frequently preceded a positive test and was associated with neurological symptoms.


Asunto(s)
Anosmia/epidemiología , COVID-19/diagnóstico , Personal de Salud/tendencias , Adulto , Anosmia/diagnóstico , Anosmia/virología , Infecciones Asintomáticas/epidemiología , COVID-19/epidemiología , Femenino , Personal de Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , SARS-CoV-2/patogenicidad , Autoinforme , Olfato/fisiología , Estados Unidos/epidemiología
16.
PLoS Biol ; 18(10): e3000867, 2020 10.
Artículo en Inglés | MEDLINE | ID: covidwho-901993

RESUMEN

The current quantitative reverse transcription PCR (RT-qPCR) assay recommended for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in the United States requires analysis of 3 genomic targets per sample: 2 viral and 1 host. To simplify testing and reduce the volume of required reagents, we devised a multiplex RT-qPCR assay to detect SARS-CoV-2 in a single reaction. We used existing N1, N2, and RP primer and probe sets by the Centers for Disease Control and Prevention, but substituted fluorophores to allow multiplexing of the assay. The cycle threshold (Ct) values of our multiplex RT-qPCR were comparable to those obtained by the single assay adapted for research purposes. Low copy numbers (≥500 copies/reaction) of SARS-CoV-2 RNA were consistently detected by the multiplex RT-qPCR. Our novel multiplex RT-qPCR improves upon current single diagnostics by saving reagents, costs, time, and labor.


Asunto(s)
Betacoronavirus/genética , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/normas , Neumonía Viral/diagnóstico , ARN Viral/genética , Juego de Reactivos para Diagnóstico/normas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Betacoronavirus/patogenicidad , COVID-19 , Prueba de COVID-19 , Estudios de Casos y Controles , Técnicas de Laboratorio Clínico/normas , Infecciones por Coronavirus/virología , Cartilla de ADN/normas , Células HEK293 , Humanos , Límite de Detección , Nasofaringe/virología , Pandemias , Neumonía Viral/virología , SARS-CoV-2 , Estados Unidos
18.
medRxiv ; 2020 Aug 04.
Artículo en Inglés | MEDLINE | ID: covidwho-721070

RESUMEN

Most currently approved strategies for the collection of saliva for COVID-19 diagnostics require specialized tubes containing buffers promoted for the stabilization of SARS-CoV-2 RNA and virus inactivation. Yet many of these are expensive, in limited supply, and not necessarily validated specifically for viral RNA. While saliva is a promising sample type as it can be reliably self-collected for the sensitive detection of SARS-CoV-2, the expense and availability of these collection tubes are prohibitive to mass testing efforts. Therefore, we investigated the stability of SARS-CoV-2 RNA and infectious virus detection from saliva without supplementation. We tested RNA stability over extended periods of time (2-25 days) and at temperatures representing at-home storage and elevated temperatures which might be experienced when cold chain transport may be unavailable. We found SARS-CoV-2 RNA in saliva from infected individuals is stable at 4°C, room temperature (~19°C), and 30°C for prolonged periods and found limited evidence for viral replication in saliva. This work demonstrates that expensive saliva collection options involving RNA stabilization and virus inactivation buffers are not always needed, permitting the use of cheaper collection options. Affordable testing methods are urgently needed to meet current testing demands and for continued surveillance in reopening strategies.

19.
Nature ; 584(7821): 463-469, 2020 08.
Artículo en Inglés | MEDLINE | ID: covidwho-677004

RESUMEN

Recent studies have provided insights into the pathogenesis of coronavirus disease 2019 (COVID-19)1-4. However, the longitudinal immunological correlates of disease outcome remain unclear. Here we serially analysed immune responses in 113 patients with moderate or severe COVID-19. Immune profiling revealed an overall increase in innate cell lineages, with a concomitant reduction in T cell number. An early elevation in cytokine levels was associated with worse disease outcomes. Following an early increase in cytokines, patients with moderate COVID-19 displayed a progressive reduction in type 1 (antiviral) and type 3 (antifungal) responses. By contrast, patients with severe COVID-19 maintained these elevated responses throughout the course of the disease. Moreover, severe COVID-19 was accompanied by an increase in multiple type 2 (anti-helminths) effectors, including interleukin-5 (IL-5), IL-13, immunoglobulin E and eosinophils. Unsupervised clustering analysis identified four immune signatures, representing growth factors (A), type-2/3 cytokines (B), mixed type-1/2/3 cytokines (C), and chemokines (D) that correlated with three distinct disease trajectories. The immune profiles of patients who recovered from moderate COVID-19 were enriched in tissue reparative growth factor signature A, whereas the profiles of those with who developed severe disease had elevated levels of all four signatures. Thus, we have identified a maladapted immune response profile associated with severe COVID-19 and poor clinical outcome, as well as early immune signatures that correlate with divergent disease trajectories.


Asunto(s)
Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/fisiopatología , Citocinas/análisis , Neumonía Viral/inmunología , Neumonía Viral/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Análisis por Conglomerados , Citocinas/inmunología , Eosinófilos/inmunología , Femenino , Humanos , Inmunoglobulina E/análisis , Inmunoglobulina E/inmunología , Interleucina-13/análisis , Interleucina-13/inmunología , Interleucina-5/análisis , Interleucina-5/inmunología , Masculino , Persona de Mediana Edad , Pandemias , Linfocitos T/citología , Linfocitos T/inmunología , Carga Viral , Adulto Joven
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