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1.
Medicina (B Aires) ; 84(1): 102-107, 2024.
Article in English | MEDLINE | ID: mdl-38271937

ABSTRACT

INTRODUCTION: After the implementation of mitigation strategies during the COVID-19 pandemic, the incidence of respiratory viruses, including human coronaviruses (HCoV), experienced a significant decrease. The aim of this study is to characterize the epidemiology and clinical aspects of HCoV infections in ambulatory adults during COVID-19 pandemic times. METHODS: descriptive, prospective, longitudinal study performed in a private hospital in La Plata, Buenos Aires, Argentina between November 2020 and October 2022; 458 outpatient adults with upper respiratory tract infections (URTI) were studied undergoing clinical and microbiological follow-up. RESULTS: 44 (9.6%) subjects were positive by multiplex PCR for HCoV. 14 of them for 229E (31.8%), 13 for OC43 (29.5%), 11 for HKU-1 (25.1%) and 6 for NL63 (13.6%). A repeated PCR was positive for the same HCoV in 19 (57%) of 33 patients on day 3-5. No hospitalizations or deaths were reported. DISCUSSION: Endemic HCoV caused a significant proportion of URTI among outpatient adults during COVID-19-related restrictions times. An alternating pattern of circulation between alfa-HCoV and beta-HCoV was observed.


Introducción: Tras la implementación de estrategias de mitigación durante la pandemia de COVID-19, la incidencia de virus respiratorios, incluyendo los coronavirus humanos (HCoV), disminuyó significativamente. El objetivo de este estudio es caracterizar la epidemiología y los aspectos clínicos de las infecciones por HCoV en adultos ambulatorios durante la pandemia de COVID-19. Métodos: estudio descriptivo, prospectivo, longitudinal, realizado en un hospital privado de La Plata, Buenos Aires, Argentina, entre noviembre de 2020 y octubre de 2022. Se estudiaron 458 pacientes adultos ambulatorios con infecciones del tracto respiratorio superior (ITRS) bajo seguimiento clínico y microbiológico. Resultados: 44 (9.6%) sujetos fueron positivos por PCR multiplex para HCoV. Se detectaron 14 229E (31.8%), 13 OC43 (29.5%), 11 HKU-1 (25.1%) y 6 NL63 (13.6%). Una segunda PCR fue positiva para el mismo HCoV en 19 (57 %) de 33 pacientes en los días 3-5. No se reportaron hospitalizaciones ni muertes. Discusión: los HCoV endémicos causaron una proporción significativa de ITRS entre pacientes adultos ambulatorios durante los tiempos de restricciones relacionados con COVID-19. Se observó un patrón alternante de circulación entre alfa-HCoV y beta-HCoV.


Subject(s)
COVID-19 , Respiratory Tract Infections , Adult , Humans , COVID-19/epidemiology , Longitudinal Studies , Pandemics , Prospective Studies , Respiratory Tract Infections/epidemiology
2.
J Infect Dis ; 229(4): 999-1009, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-37527470

ABSTRACT

BACKGROUND: The Global Influenza Hospital Surveillance Network (GIHSN) has since 2012 provided patient-level data on severe influenza-like-illnesses from >100 participating clinical sites worldwide based on a core protocol and consistent case definitions. METHODS: We used multivariable logistic regression to assess the risk of intensive care unit admission, mechanical ventilation, and in-hospital death among hospitalized patients with influenza and explored the role of patient-level covariates and country income level. RESULTS: The data set included 73 121 patients hospitalized with respiratory illness in 22 countries, including 15 660 with laboratory-confirmed influenza. After adjusting for patient-level covariates we found a 7-fold increase in the risk of influenza-related intensive care unit admission in lower middle-income countries (LMICs), compared with high-income countries (P = .01). The risk of mechanical ventilation and in-hospital death also increased by 4-fold in LMICs, though these differences were not statistically significant. We also find that influenza mortality increased significantly with older age and number of comorbid conditions. Across all severity outcomes studied and after controlling for patient characteristics, infection with influenza A/H1N1pdm09 was more severe than with A/H3N2. CONCLUSIONS: Our study provides new information on influenza severity in underresourced populations, particularly those in LMICs.


Subject(s)
Influenza, Human , Humans , Influenza, Human/epidemiology , Influenza A Virus, H3N2 Subtype , Hospital Mortality , Hospitalization , Hospitals
3.
Medicina (B.Aires) ; 83(5): 719-726, dic. 2023. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1534875

ABSTRACT

Resumen Introducción : Durante la pandemia de SARS-CoV-2 en Argentina se implementaron intervenciones no farma cológicas que produjeron cambios en la movilidad de la población. El objetivo de este estudio fue relacionar los porcentajes de positividad y la diversidad viral con la movi lidad poblacional durante parte del período de restricciones. Métodos : Estudio retrospectivo analítico realizado en el Instituto Médico Platense durante los años 2020 a 2022 que incluyó 458 pacientes a los que se les tomó un hisopado nasofaríngeo para la búsqueda de patóge nos respiratorios por PCR multiplex. Se analizaron los cambios en la movilidad de la población utilizando los "Informes de Movilidad Local", herramienta desarrollada por Google, cuyos datos son de público acceso. Resultados : La movilidad poblacional se correlacionó significativamente con el porcentaje de positividad de las muestras (p = <0.01; R2 = 0.89) y la diversidad viral (p = 0.04; R2 = 0.78). Discusión : Las intervenciones no farmacológicas destinadas a limitar la propagación del SARS-CoV-2 tuvieron efecto en la circulación de otros virus respi ratorios, hallándose mayor porcentaje de positividad y diversidad a medida que las mismas disminuyeron su grado de restricción.


Abstract Introduction : During the SARS-CoV-2 pandemic, Ar gentina population suffered from significant changes in population mobility due to non-pharmaceutical interventions. The aim of this study was to describe the impact of the mobility restrictions to the rates of positivity and diversity among different respiratory viruses. Methods : Retrospective analytical study per formed at Instituto Médico Platense in La Plata that included 458 patients with nasopharyngeal swab to search for respiratory pathogens by multiplex PCR. Changes in mobility were studied using "Community Mobility Reports", data set developed by Google and publicly available. Results : Community mobility had significant cor relation with the percentages of viral test positiv ity (p = < 0.01; R2=0.89) and viral diversity (p = 0.04; R2 = 0.78). Discussion : Non-pharmaceutical interventions estab lished to contain SARS-CoV-2 spread had a significant impact in the circulation patterns of other respiratory viruses.

4.
Medicina (B Aires) ; 83(5): 719-726, 2023.
Article in Spanish | MEDLINE | ID: mdl-37870329

ABSTRACT

INTRODUCTION: During the SARS-CoV-2 pandemic, Argentina population suffered from significant changes in population mobility due to non-pharmaceutical interventions. The aim of this study was to describe the impact of the mobility restrictions to the rates of positivity and diversity among different respiratory viruses. METHODS: Retrospective analytical study performed at Instituto Médico Platense in La Plata that included 458 patients with nasopharyngeal swab to search for respiratory pathogens by multiplex PCR. Changes in mobility were studied using "Community Mobility Reports", data set developed by Google and publicly available. RESULTS: Community mobility had significant correlation with the percentages of viral test positivity (p = < 0.01; R2=0.89) and viral diversity (p = 0.04; R2 = 0.78). DISCUSSION: Non-pharmaceutical interventions established to contain SARS-CoV-2 spread had a significant impact in the circulation patterns of other respiratory viruses.


Introducción: Durante la pandemia de SARS-CoV-2 en Argentina se implementaron intervenciones no farmacológicas que produjeron cambios en la movilidad de la población. El objetivo de este estudio fue relacionar los porcentajes de positividad y la diversidad viral con la movilidad poblacional durante parte del período de restricciones. Métodos: Estudio retrospectivo analítico realizado en el Instituto Médico Platense durante los años 2020 a 2022 que incluyó 458 pacientes a los que se les tomó un hisopado nasofaríngeo para la búsqueda de patógenos respiratorios por PCR multiplex. Se analizaron los cambios en la movilidad de la población utilizando los "Informes de Movilidad Local", herramienta desarrollada por Google, cuyos datos son de público acceso. Resultados: La movilidad poblacional se correlacionó significativamente con el porcentaje de positividad de las muestras (p = <0.01; R2 = 0.89) y la diversidad viral (p = 0.04; R2 = 0.78). Discusión: Las intervenciones no farmacológicas destinadas a limitar la propagación del SARS-CoV-2 tuvieron efecto en la circulación de otros virus respiratorios, hallándose mayor porcentaje de positividad y diversidad a medida que las mismas disminuyeron su grado de restricción.


Subject(s)
COVID-19 , Humans , SARS-CoV-2 , Pandemics , Retrospective Studies , Argentina/epidemiology
5.
NPJ Vaccines ; 8(1): 149, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37794010

ABSTRACT

COVID-19 vaccines were originally designed based on the ancestral Spike protein, but immune escape of emergent Variants of Concern (VOC) jeopardized their efficacy, warranting variant-proof vaccines. Here, we used preclinical rodent models to establish the cross-protective and cross-neutralizing capacity of adenoviral-vectored vaccines expressing VOC-matched Spike. CoroVaxG.3-D.FR, matched to Delta Plus Spike, displayed the highest levels of nAb to the matched VOC and mismatched variants. Cross-protection against viral infection in aged K18-hACE2 mice showed dramatic differences among the different vaccines. While Delta-targeted vaccines fully protected mice from a challenge with Gamma, a Gamma-based vaccine offered only partial protection to Delta challenge. Administration of CorovaxG.3-D.FR in a prime/boost regimen showed that a booster was able to increase the neutralizing capacity of the sera against all variants and fully protect aged K18-hACE2 mice against Omicron BA.1, as a BA.1-targeted vaccine did. The neutralizing capacity of the sera diminished in all cases against Omicron BA.2 and BA.5. Altogether, the data demonstrate that a booster with a vaccine based on an antigenically distant variant, such as Delta or BA.1, has the potential to protect from a wider range of SARS-CoV-2 lineages, although careful surveillance of breakthrough infections will help to evaluate combination vaccines targeting antigenically divergent variants yet to emerge.

6.
Open Forum Infect Dis ; 10(6): ofad244, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37383245

ABSTRACT

Background: The Global Influenza Hospital Surveillance Network (GIHSN) was established in 2012 to conduct coordinated worldwide influenza surveillance. In this study, we describe underlying comorbidities, symptoms, and outcomes in patients hospitalized with influenza. Methods: Between November 2018 and October 2019, GIHSN included 19 sites in 18 countries using a standardized surveillance protocol. Influenza infection was laboratory-confirmed with reverse-transcription polymerase chain reaction. A multivariate logistic regression model was utilized to analyze the extent to which various risk factors predict severe outcomes. Results: Of 16 022 enrolled patients, 21.9% had laboratory-confirmed influenza; 49.2% of influenza cases were A/H1N1pdm09. Fever and cough were the most common symptoms, although they decreased with age (P < .001). Shortness of breath was uncommon among those <50 years but increased with age (P < .001). Middle and older age and history of underlying diabetes or chronic obstructive pulmonary disease were associated with increased odds of death and intensive care unit (ICU) admission, and male sex and influenza vaccination were associated with lower odds. The ICU admissions and mortality occurred across the age spectrum. Conclusions: Both virus and host factors contributed to influenza burden. We identified age differences in comorbidities, presenting symptoms, and adverse clinical outcomes among those hospitalized with influenza and benefit from influenza vaccination in protecting against adverse clinical outcomes. The GIHSN provides an ongoing platform for global understanding of hospitalized influenza illness.

7.
BMC Infect Dis ; 23(1): 165, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36932346

ABSTRACT

BACKGROUND: In yellow fever (YF) endemic areas, measles, mumps, and rubella (MMR), and YF vaccines are often co-administered in childhood vaccination schedules. Because these are live vaccines, we assessed potential immune interference that could result from co-administration. METHODS: We conducted an open-label, randomized non-inferiority trial among healthy 1-year-olds in Misiones Province, Argentina. Children were randomized to one of three groups (1:1:1): Co-administration of MMR and YF vaccines (MMR1YF1), MMR followed by YF vaccine four weeks later (MMR1YF2), or YF followed by MMR vaccine four weeks later (YF1MMR2). Blood samples obtained pre-vaccination and 28 days post-vaccination were tested for immunoglobulin G antibodies against measles, mumps, and rubella, and for YF virus-specific neutralizing antibodies. Non-inferiority in seroconversion was assessed using a -5% non-inferiority margin. Antibody concentrations were compared with Kruskal-Wallis tests. RESULTS: Of 851 randomized children, 738 were correctly vaccinated, had ≥ 1 follow-up sample, and were included in the intention-to-treat population. Non-inferior seroconversion was observed for all antigens (measles seroconversion: 97.9% in the MMR1YF1 group versus 96.3% in the MMR1YF2 group, a difference of 1.6% [90% CI -1.5, 4.7]; rubella: 97.9% MMR1YF1 versus 94.7% MMR1YF2, a difference of 3.3% [-0.1, 6.7]; mumps: 96.7% MMR1YF1 versus 97.9% MMR1YF2, a difference of -1.3% [-4.1, 1.5]; and YF: 96.3% MMR1YF1 versus 97.5% YF1MMR2, a difference of -1.2% [-4.2, 1.7]). Rubella antibody concentrations and YF titers were significantly lower following co-administration; measles and mumps concentrations were not impacted. CONCLUSION: Effective seroconversion was achieved and was not impacted by the co-administration, although antibody levels for two antigens were lower. The impact of lower antibody levels needs to be weighed against missed opportunities for vaccination to determine optimal timing for MMR and YF vaccine administration. TRIAL REGISTRATION: The study was retrospectively registered in ClinicalTrials.gov (NCT03368495) on 11/12/2017.


Subject(s)
Measles , Mumps , Rubella , Yellow Fever Vaccine , Yellow Fever , Humans , Child , Infant , Mumps/prevention & control , Argentina , Measles-Mumps-Rubella Vaccine , Antibodies, Viral , Rubella/prevention & control , Measles/prevention & control , Immunity , Vaccines, Combined
8.
Influenza Other Respir Viruses ; 17(1): e13073, 2023 01.
Article in English | MEDLINE | ID: mdl-36824313

ABSTRACT

Background: External quality assessments (EQAs) for the molecular detection of human respiratory syncytial virus (RSV) are necessary to ensure the standardisation of reliable results. The Phase II, 2019-2020 World Health Organization (WHO) RSV EQA included 28 laboratories in 26 countries. The EQA panel evaluated performance in the molecular detection and subtyping of RSV-A and RSV-B. This manuscript describes the preparation, distribution, and analysis of the 2019-2020 WHO RSV EQA. Methods: Panel isolates underwent whole genome sequencing and in silico primer matching. The final panel included nine contemporary, one historical virus and two negative controls. The EQA panel was manufactured and distributed by the UK National External Quality Assessment Service (UK NEQAS). National laboratories used WHO reference assays developed by the United States Centers for Disease Control and Prevention, an RSV subtyping assay developed by the Victorian Infectious Diseases Reference Laboratory (Australia), or other in-house or commercial assays already in use at their laboratories. Results: An in silico analysis of isolates showed a good match to assay primer/probes. The panel was distributed to 28 laboratories. Isolates were correctly identified in 98% of samples for detection and 99.6% for subtyping. Conclusions: The WHO RSV EQA 2019-2020 showed that laboratories performed at high standards. Updating the composition of RSV molecular EQAs with contemporary strains to ensure representation of circulating strains, and ensuring primer matching with EQA panel viruses, is advantageous in assessing diagnostic competencies of laboratories. Ongoing EQAs are recommended because of continued evolution of mismatches between current circulating strains and existing primer sets.


Subject(s)
Respiratory Syncytial Virus, Human , Viruses , United States , Humans , Respiratory Syncytial Virus, Human/genetics , Laboratories , World Health Organization , Australia
9.
Biomed J ; 46(1): 81-92, 2023 02.
Article in English | MEDLINE | ID: mdl-35948250

ABSTRACT

BACKGROUND: Severe cases of Coronavirus Disease 2019 (COVID-19) that require admission to the Intensive Care Unit (ICU) and mechanical ventilation assistance show a high mortality rate with currently few therapeutic options available. Severe COVID-19 is characterized by a systemic inflammatory condition, also called "cytokine storm", which can lead to various multi-organ complications and ultimately death. Lidocaine, a safe local anesthetic that given intravenously is used to treat arrhythmias, has long been reported to have an anti-inflammatory and pro-homeostatic activity. METHODS: We studied the capacity of lidocaine to modulate cytokine secretion of mouse and human myeloid cell lines activated by different cytokines or Toll Like Receptor (TLR) ligands (flagellin (FliC), Lipopolysaccharide (LPS), Polyinosinic:polycytidylic acid (Poly I:C) and N-Palmitoyl-S- [2,3-bis(palmitoyloxy)-(2RS)-propyl]-(R)-cysteinyl-(S)-seryl-(S)-lysyl-(S)-lysyl-(S)-lysyl-(S)-lysine x 3HCl (Pam3Cys-SKKKK)) or by Severe acute respiratory syndromecoronavirus 2 (SARS-CoV-2) infection to epithelial cells. Reporter cell lines were used to study modulation of lidocaine of specific signaling pathways. RESULTS: Lidocaine used in combination with dexamethasone, had an additive effect in the modulation of cellular inflammatory response triggered by Tumoral Necrosis Factor alpha (TNFα), Interleukin 1 beta (IL-1ß) as well as different TLR ligands. We also found that lidocaine in combination with dexamethasone modulates the Nuclear factor kappa B (NF-κB) pathway, inflammasome activation as well as interferon gamma receptor (IFNγR) signaling without affecting the type I interferons (Type I IFNs) pathway. Furthermore, we showed that lidocaine and dexamethasone treatment of epithelial cells infected with SARS-CoV-2 modulated the expression of chemokines that contribute to pro-inflammatory effects in severe COVID. CONCLUSIONS: We reported for the first time in vitro anti-inflammatory capacity of lidocaine on SARS-CoV-2 triggered immune pathways. These results indicated the potential of lidocaine to treat COVID-19 patients and add tools to the therapeutic options available for these concerning cases.


Subject(s)
COVID-19 , Cytokines , Humans , Cytokines/metabolism , SARS-CoV-2 , Lidocaine/pharmacology , COVID-19 Drug Treatment , Anti-Inflammatory Agents/pharmacology , Epithelial Cells/metabolism , Toll-Like Receptors , Dexamethasone/pharmacology
10.
Microbiol Spectr ; 10(6): e0314322, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36222689

ABSTRACT

Bats are reservoirs of diverse coronaviruses (CoVs), including progenitors of severe acute respiratory syndrome CoV (SARS-CoV) and SARS-CoV-2. In the Americas, there is a contrast between alphacoronaviruses (alphaCoVs) and betaCoVs: while cospeciation prevails in the latter, alphaCoV evolution is dominated by deep and recent host switches. AlphaCoV lineages are maintained by two different bat family groups, Phyllostomidae and Vespertilionidae plus Molossidae. In this study, we used a Bayesian framework to analyze the process of diversification of the lineages maintained by Molossidae and Vespertilionidae, adding novel CoV sequences from Argentina. We provide evidence that the observed CoV diversity in these two bat families is shaped by their geographic distribution and that CoVs exhibit clustering at the level of bat genera. We discuss the causes of the cocirculation of two independent clades in Molossus and Tadarida as well as the role of Myotis as the ancestral host and a major evolutionary reservoir of alphaCoVs across the continent. Although more CoV sampling efforts are needed, these findings contribute to a better knowledge of the diversity of alphaCoVs and the links between bat host species. IMPORTANCE Bats harbor the largest diversity of coronaviruses among mammals. In the Americas, seven alphacoronavirus lineages circulate among bats. Three of these lineages are shared by members of two bat families: Vespertilionidae and Molossidae. Uncovering the relationships between these coronaviruses can help us to understand patterns of cross-species transmission and, ultimately, which hosts are more likely to be involved in spillover events. We found that two different lineages cocirculate among the bat genera Molossus and Tadarida, which share roosts and have common viral variants. The bat genus Myotis functions as a reservoir of coronavirus diversity and, as such, is a key host. Although there were some spillovers recorded, there is a strong host association, showing that once a successful host jump takes place, it is transmitted onward to members of the same bat genus.


Subject(s)
Alphacoronavirus , COVID-19 , Chiroptera , Humans , Animals , Bayes Theorem , Phylogeny , SARS-CoV-2/genetics , Americas
11.
J Virol Methods ; 297: 114272, 2021 11.
Article in English | MEDLINE | ID: mdl-34454988

ABSTRACT

The aim of this study was to set up a simple protocol to concentrate SARS-CoV-2 from sewage, which can be implemented in laboratories with minimal equipment resources. The method avoids the need for extensive purification steps and reduces the concentration of potential inhibitors of RT-qPCR contained in sewage. The concentration method consists of a single step, in which a small volume (40 mL) of sewage sample is incubated with polyaluminum chloride (PAC)(0.00045 N Al3+ final concentration). Virus particles adsorbed to the precipitate are collected by low-speed centrifugation, after which the recovered pellet is resuspended with a saline buffer. PAC-concentrated samples are stable for at least one week at 4 °C. Therefore, they may be sent refrigerated to a diagnosis center for RNA extraction and RT-qPCR for SARS-CoV-2 RNA detection if the lab does not have such capabilities. The PAC concentration method produced an average shift of 4.5-units in quantification cycle (Cq) values compared to non-concentrated samples, indicating a 25-fold increase in detection sensitivity. The lower detection limit corresponded approximately to 100 viral copies per ml. Kappa index indicated substantial agreement between PAC and polyethylene glycol (PEG) precipitation protocols (k = 0.688, CI 0.457-0.919). This low-cost concentration protocol could be useful to aid in the monitoring of community circulation of SARS-CoV-2, especially in low- and middle-income countries, which do not have massive access to support from specialized labs for sewage surveillance.


Subject(s)
COVID-19 , Sewage , Humans , RNA, Viral , SARS-CoV-2 , Wastewater
12.
RNA Biol ; 18(12): 2218-2225, 2021 12.
Article in English | MEDLINE | ID: mdl-33966602

ABSTRACT

Early detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been proven crucial during the efforts to mitigate the effects of the COVID-19 pandemic. Several diagnostic methods have emerged in the past few months, each with different shortcomings and limitations. The current gold standard, RT-qPCR using fluorescent probes, relies on demanding equipment requirements plus the high costs of the probes and specific reaction mixes. To broaden the possibilities of reagents and thermocyclers that could be allocated towards this task, we have optimized an alternative strategy for RT-qPCR diagnosis. This is based on a widely used DNA-intercalating dye and can be implemented with several different qPCR reagents and instruments. Remarkably, the proposed qPCR method performs similarly to the broadly used TaqMan-based detection, in terms of specificity and sensitivity, thus representing a reliable tool. We think that, through enabling the use of vast range of thermocycler models and laboratory facilities for SARS-CoV-2 diagnosis, the alternative proposed here can increase dramatically the testing capability, especially in countries with limited access to costly technology and reagents.


Subject(s)
Benzothiazoles/chemistry , COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Diamines/chemistry , Intercalating Agents/chemistry , Quinolines/chemistry , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , COVID-19/virology , COVID-19 Nucleic Acid Testing/standards , DNA/analysis , DNA/biosynthesis , DNA Primers/chemistry , DNA Primers/metabolism , Humans , Nasopharynx/virology , Real-Time Polymerase Chain Reaction/standards , Sensitivity and Specificity
13.
Genes (Basel) ; 12(5)2021 04 28.
Article in English | MEDLINE | ID: mdl-33924826

ABSTRACT

Our aim was to evaluate the analytical and clinical performance of the SARS-CoV-2 molecular detection kits used in Argentina. Nine real-time reverse-transcription polymerase chain reaction (RT-qPCR) and three reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assays were evaluated using the World Health Organization (WHO) recommended test as reference method. A secondary standard calibrated for the E, N and RdRp genes against the Pan American Health Organization-World Health Organization-International Standard was used to calculate the limit of detection (LoD). A panel of artificial clinical samples, 32 positive and 30 negative for SARS-CoV-2, were analyzed to estimate the kappa concordance (κ) and the diagnostic performance. Differences among the LoD values for the target genes amplified by each kit were >1 log copies/reaction. The κ for the RT-qPCR kits was greater than 0.9, whereas that for the RT-LAMP assays ranged from 0.75 to 0.93. The clinical performance of RT-qPCR kits showed 100% specificity and high sensitivity, although with variations according to the gene analyzed. The E and N genes provided greater clinical sensitivity, whereas the RdRp gene increased the clinical specificity. The RT-LAMP assays revealed a variable diagnostic performance. The information provided can be useful to choose the most appropriate diagnostic test and may contribute to the establishment of a consensus in the diagnosis of SARS-CoV-2 in Argentina and the region.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Real-Time Polymerase Chain Reaction/methods , Argentina , Calibration , Humans , Limit of Detection , SARS-CoV-2/genetics
14.
Front Vet Sci ; 7: 603622, 2020.
Article in English | MEDLINE | ID: mdl-33240967

ABSTRACT

Interferon lambda (IFN-λ) is an antiviral naturally produced in response to viral infections, with activity on cells of epithelial origin and located in the mucosal surfaces. This localized activity results in reduced toxicity compared to type I IFNs, whose receptors are ubiquitously expressed. IFN-λ has been effective in the therapy of respiratory viral infections, playing a crucial role in potentiating adaptive immune responses that initiate at mucosal surfaces. Human IFN-λ has polymorphisms that may cause differences in the interaction with the specific receptor in the human population. Interestingly, bovine IFN-λ3 has an in silico-predicted higher affinity for the human receptor than its human counterparts, with high identity with different human IFN-λ variants, making it a suitable antiviral therapeutic candidate for human health. Here, we demonstrate that a recombinant bovine IFN-λ (rbIFN-λ) produced in HEK-293 cells is effective in preventing SARS-CoV-2 infection of VERO cells, with an inhibitory concentration 50% (IC50) between 30 and 50 times lower than that of human type I IFN tested here (α2b and ß1a). We also demonstrated the absence of toxicity of rbIFN-λ in human PBMCs and the lack of proinflammatory activity on these cells. Altogether, our results show that rbIFN-λ is as an effective antiviral potentially suitable for COVID-19 therapy. Among other potential applications, rbIFN-λ could be useful to preclude virus dispersion to the lungs and/or to reduce transmission from infected people. Moreover, and due to the non-specific activity of this IFN, it can be potentially effective against other respiratory viruses that may be circulating together with SARS-CoV-2.

15.
J Virol Methods ; 286: 113991, 2020 12.
Article in English | MEDLINE | ID: mdl-33045283

ABSTRACT

Coronavirus disease 2019, known as COVID-19, is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The early, sensitive and specific detection of SARS-CoV-2 virus is widely recognized as the critical point in responding to the ongoing outbreak. Currently, the diagnosis is based on molecular real time RT-PCR techniques, although their implementation is being threatened due to the extraordinary demand for supplies worldwide. That is why the development of alternative and / or complementary tests becomes so relevant. Here, we exploit the potential of mass spectrometry technology combined with machine learning algorithms, for the detection of COVID-19 positive and negative protein profiles directly from nasopharyngeal swabs samples. According to the preliminary results obtained, accuracy = 67.66 %, sensitivity = 61.76 %, specificity = 71.72 %, and although these parameters still need to be improved to be used as a screening technique, mass spectrometry-based methods coupled with multivariate analysis showed that it is an interesting tool that deserves to be explored as a complementary diagnostic approach due to the low cost and fast performance. However, further steps, such as the analysis of a large number of samples, should be taken in consideration to determine the applicability of the method developed.


Subject(s)
Betacoronavirus/isolation & purification , Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Nasopharynx/virology , Pneumonia, Viral/virology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , COVID-19 , COVID-19 Testing , COVID-19 Vaccines , Coronavirus Infections/virology , Humans , Machine Learning , Mass Screening/methods , Multivariate Analysis , Pandemics , Pneumonia, Viral/diagnosis , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , Sensitivity and Specificity
16.
Medicina (B Aires) ; 80 Suppl 3: 1-6, 2020.
Article in English | MEDLINE | ID: mdl-32658841

ABSTRACT

The disease named COVID-19, caused by the SARS-CoV-2 coronavirus, is currently generating a global pandemic. Vaccine development is no doubt the best long-term immunological approach, but in the current epidemiologic and health emergency there is a need for rapid and effective solutions. Convalescent plasma is the only antibody-based therapy available for COVID-19 patients to date. Equine polyclonal antibodies (EpAbs) put forward a sound alternative. The new generation of processed and purified EpAbs containing highly purified F(ab')2 fragments demonstrated to be safe and well tolerated. EpAbs are easy to manufacture allowing a fast development and scaling up for a treatment. Based on these ideas, we present a new therapeutic product obtained after immunization of horses with the receptor-binding domain of the viral Spike glycoprotein. Our product shows around 50 times more potency in in vitro seroneutralization assays than the average of convalescent plasma. This result may allow us to test the safety and efficacy of this product in a phase 2/3 clinical trial to be conducted in July 2020 in the metropolitan area of Buenos Aires, Argentina.


La enfermedad denominada COVID-19 es causada por el coronavirus SARS-CoV-2 y es actualmente considerada una pandemia a nivel global. El desarrollo de vacunas es sin duda la mejor estrategia a largo plazo, pero debido a la emergencia sanitaria, existe una necesidad urgente de encontrar soluciones rápidas y efectivas para el tratamiento de la enfermedad. Hasta la fecha, el uso de plasma de convalecientes es la única inmunoterapia disponible para pacientes hospitalizados con COVID-19. El uso de anticuerpos policlonales equinos (EpAbs) es otra alternativa terapéutica interesante. La nueva generación de EpAbs incluyen el procesamiento y purificación de los mismos y la obtención de fragmentos F(ab')2 con alta pureza y un excelente perfil de seguridad en humanos. Los EpAbs son fáciles de producir, lo cual permite el desarrollo rápido y la elaboración a gran escala de un producto terapéutico. En este trabajo mostramos el desarrollo de un suero terapéutico obtenido luego de la inmunización de caballos utilizando el receptor-binding domain de la glicoproteína Spike del virus. Nuestro producto mostró ser alrededor de 50 veces más potente en ensayos de seroneutralización in vitro que el promedio de los plasmas de convalecientes. Estos resultados nos permitirían testear la seguridad y eficacia de nuestro producto en ensayos clínicos de fase 2/3 a realizarse a partir de julio de 2020 en la zona metropolitana de Buenos Aires, Argentina.


Subject(s)
Antibodies, Viral , Coronavirus Infections/therapy , Immune Sera/immunology , Immunoglobulin Fab Fragments/isolation & purification , Immunoglobulin G/isolation & purification , Pandemics , Pneumonia, Viral , Spike Glycoprotein, Coronavirus , Animals , Antibodies, Viral/chemistry , Antibodies, Viral/immunology , Antibodies, Viral/isolation & purification , Argentina , Betacoronavirus , COVID-19 , Horses , Humans , Immunization, Passive , Immunoglobulin Fab Fragments/chemistry , Immunoglobulin G/chemistry , Neutralization Tests , SARS-CoV-2 , COVID-19 Serotherapy
17.
Influenza Other Respir Viruses ; 14(6): 671-677, 2020 11.
Article in English | MEDLINE | ID: mdl-32730685

ABSTRACT

BACKGROUND: External quality assessments (EQAs) for the molecular detection of respiratory syncytial virus (RSV) are necessary to ensure the provision of reliable and accurate results. One of the objectives of the pilot of the World Health Organization (WHO) Global RSV Surveillance, 2016-2017, was to evaluate and standardize RSV molecular tests used by participating countries. This paper describes the first WHO RSV EQA for the molecular detection of RSV. METHODS: The WHO implemented the pilot of Global RSV Surveillance based on the WHO Global Influenza Surveillance and Response System (GISRS) from 2016 to 2018 in 14 countries. To ensure standardization of tests, 13 participating laboratories were required to complete a 12 panel RSV EQA prepared and distributed by the Centers for Disease Control and Prevention (CDC), USA. The 14th laboratory joined the pilot late and participated in a separate EQA. Laboratories evaluated a RSV rRT-PCR assay developed by CDC and compared where applicable, other Laboratory Developed Tests (LDTs) or commercial assays already in use at their laboratories. RESULTS: Laboratories performed well using the CDC RSV rRT-PCR in comparison with LDTs and commercial assays. Using the CDC assay, 11 of 13 laboratories reported correct results. Two laboratories each reported one false-positive finding. Of the laboratories using LDTs or commercial assays, results as assessed by Ct values were 100% correct for 1/5 (20%). With corrective actions, all laboratories achieved satisfactory outputs. CONCLUSIONS: These findings indicate that reliable results can be expected from this pilot. Continued participation in EQAs for the molecular detection of RSV is recommended.


Subject(s)
Quality Assurance, Health Care/statistics & numerical data , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus, Human/isolation & purification , Humans , Laboratories/standards , Molecular Diagnostic Techniques/standards , Pilot Projects , RNA, Viral/genetics , Respiratory Syncytial Virus, Human/genetics , World Health Organization
18.
Medicina (B.Aires) ; 80(supl.3): 1-6, June 2020. ilus, graf, tab
Article in English | LILACS | ID: biblio-1135184

ABSTRACT

The disease named COVID-19, caused by the SARS-CoV-2 coronavirus, is currently generating a global pandemic. Vaccine development is no doubt the best long-term immunological approach, but in the current epidemiologic and health emergency there is a need for rapid and effective solutions. Convalescent plasma is the only antibody-based therapy available for COVID-19 patients to date. Equine polyclonal antibodies (EpAbs) put forward a sound alternative. The new generation of processed and purified EpAbs containing highly purified F(ab’)2 fragments demonstrated to be safe and well tolerated. EpAbs are easy to manufacture allowing a fast development and scaling up for a treatment. Based on these ideas, we present a new therapeutic product obtained after immunization of horses with the receptor-binding domain of the viral Spike glycoprotein. Our product shows around 50 times more potency in in vitro seroneutralization assays than the average of convalescent plasma. This result may allow us to test the safety and efficacy of this product in a phase 2/3 clinical trial to be conducted in July 2020 in the metropolitan area of Buenos Aires, Argentina.


La enfermedad denominada COVID-19 es causada por el coronavirus SARS-CoV-2 y es actualmente considerada una pandemia a nivel global. El desarrollo de vacunas es sin duda la mejor estrategia a largo plazo, pero debido a la emergencia sanitaria, existe una necesidad urgente de encontrar soluciones rápidas y efectivas para el tratamiento de la enfermedad. Hasta la fecha, el uso de plasma de convalecientes es la única inmunoterapia disponible para pacientes hospitalizados con COVID-19. El uso de anticuerpos policlonales equinos (EpAbs) es otra alternativa terapéutica interesante. La nueva generación de EpAbs incluyen el procesamiento y purificación de los mismos y la obtención de fragmentos F(ab’)2 con alta pureza y un excelente perfil de seguridad en humanos. Los EpAbs son fáciles de producir, lo cual permite el desarrollo rápido y la elaboración a gran escala de un producto terapéutico. En este trabajo mostramos el desarrollo de un suero terapéutico obtenido luego de la inmunización de caballos utilizando el receptor-binding domain de la glicoproteína Spike del virus. Nuestro producto mostró ser alrededor de 50 veces más potente en ensayos de seroneutralización in vitro que el promedio de los plasmas de convalecientes. Estos resultados nos permitirían testear la seguridad y eficacia de nuestro producto en ensayos clínicos de fase 2/3 a realizarse a partir de julio de 2020 en la zona metropolitana de Buenos Aires, Argentina.


Subject(s)
Humans , Animals , Immunoglobulin Fab Fragments/isolation & purification , Coronavirus Infections/therapy , Immune Sera/immunology , Antibodies, Viral/isolation & purification , Antibodies, Viral/immunology , Antibodies, Viral/chemistry , Argentina , Immunoglobulin G/isolation & purification , Immunoglobulin G/chemistry , Immunoglobulin Fab Fragments/chemistry , Neutralization Tests , Pandemics , Betacoronavirus , SARS-CoV-2 , COVID-19 , Horses
19.
PLoS One ; 15(3): e0227962, 2020.
Article in English | MEDLINE | ID: mdl-32155152

ABSTRACT

OBJECTIVE: Since the 2009 influenza pandemic, Latin American (LA) countries have strengthened their influenza surveillance systems. We analyzed influenza genetic sequence data from the 2017 through 2018 Southern Hemisphere (SH) influenza season from selected LA countries, to map the availability of influenza genetic sequence data from, and to describe, the 2017 through 2018 SH influenza seasons in LA. METHODS: We analyzed influenza A/H1pdm09, A/H3, B/Victoria and B/Yamagata hemagglutinin sequences from clinical samples from 12 National Influenza Centers (NICs) in ten countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Mexico, Paraguay, Peru and Uruguay) with a collection date from epidemiologic week (EW) 18, 2017 through EW 43, 2018. These sequences were generated by the NIC or the WHO Collaborating Center (CC) at the U.S Centers for Disease Control and Prevention, uploaded to the Global Initiative on Sharing All Influenza Data (GISAID) platform, and used for phylogenetic reconstruction. FINDINGS: Influenza hemagglutinin sequences from the participating countries (A/H1pdm09 n = 326, A/H3 n = 636, B n = 433) were highly concordant with the genetic groups of the influenza vaccine-recommended viruses for influenza A/H1pdm09 and influenza B. For influenza A/H3, the concordance was variable. CONCLUSIONS: Considering the constant evolution of influenza viruses, high-quality surveillance data-specifically genetic sequence data, are important to allow public health decision makers to make informed decisions about prevention and control strategies, such as influenza vaccine composition. Countries that conduct influenza genetic sequencing for surveillance in LA should continue to work with the WHO CCs to produce high-quality genetic sequence data and upload those sequences to open-access databases.


Subject(s)
Evolution, Molecular , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Orthomyxoviridae/genetics , Pandemics/prevention & control , Datasets as Topic , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Humans , Influenza Vaccines/immunology , Influenza, Human/epidemiology , Influenza, Human/microbiology , Latin America/epidemiology , Orthomyxoviridae/immunology , Orthomyxoviridae/isolation & purification , Phylogeny
20.
Influenza Other Respir Viruses ; 14(6): 638-646, 2020 11.
Article in English | MEDLINE | ID: mdl-32163226

ABSTRACT

BACKGROUND: Human respiratory syncytial virus (RSV) causes illnesses among all age groups and presents a burden to healthcare services. To better understand the epidemiology and seasonality of RSV in different geographical areas, the World Health Organization (WHO) coordinated a pilot initiative to access the feasibility of establishing RSV surveillance using the existing Global Influenza Surveillance and Response System (GISRS) platform. OBJECTIVES: To describe and compare RSV and influenza seasonality in countries in the northern andsouthern temperate, and tropics during the period January 2017 to April 2019. METHODS: Fourteen countries in six WHO regions participating in the GISRS were invited for the pilot. Hospitalized patients presenting with severe acute respiratory illness (SARI), SARI without fever and outpatients presenting with acute respiratory illness (ARI) were enrolled from January 2017 to April 2019. The expected minimum sample size was 20 samples per week, year-round, per country. Real-time RT-PCR was used to detect RSV and influenza viruses. Results were uploaded to the WHO FluMart platform. RESULTS: Annual seasonality of RSV was observed in all countries, which overlapped to a large extent with the influenza activity. In countries, in temperate regions RSV peaked in the autumn/winter months. In Egypt, a subtropical country, RSV activity peaked in the cooler season. In the tropical regions, RSV peaked during the rainy seasons. CONCLUSION: Early findings from the WHO RSV surveillance pilot based on the GISRS suggest annual seasonal patterns for of RSV circulation that overlap with influenza. RSV surveillance needs to be continued for several more seasons to establish seasonality patterns to inform prevention and control strategies.


Subject(s)
Influenza, Human/epidemiology , Respiratory Syncytial Virus Infections/epidemiology , Sentinel Surveillance , Global Health , Humans , Influenza, Human/diagnosis , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , Pilot Projects , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Virus, Human/isolation & purification , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , Seasons , World Health Organization
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