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1.
New Microbiol ; 46(2): 170-185, 2023 May.
Article in English | MEDLINE | ID: covidwho-20232751

ABSTRACT

The effects of clinical symptoms, laboratory indicators, and comorbidity status of SARS-CoV-2-infected patients on the severity of disease and the risk of death were investigated. Questionnaires and electronic medical records of 371 hospitalized COVID-19 patients were used for data collection (demographics, clinical manifestation, comorbidities, laboratory data). Association among categorical variables was determined using Kolmogorov-Smirnov test (P-value ≤0.05). Median age of study population (249 males, 122 females) was 65 years. Roc curves analysis found that age ≥64 years and age ≥67 years are significant cut-offs identifying patients with more severe disease and mortality at 30 days. CRP values at cut-off ≥80.7 and ≥95.8 significantly identify patients with more severe disease and mortality. Patients with more severe disease and risk of death were significantly identified with platelet value at the cut-off ≤160,000, hemoglobin value at the cut-off ≤11.7, D-Dimer values ≥1383 and ≥1270, and with values of neutrophil granulocytes (≥8.2 and ≤2) and lymphocytes (≤2 and ≤2.4). Detailed clinical investigation suggests granulocytes together with lymphopenia may be a potential indicator for diagnosis. Older age, several comorbidities (cancer, cardiovascular diseases, hypertension) and more laboratory abnormalities (CRP, D-Dimer, platelets, hemoglobin) were associated with development of more severity and mortality among COVID-19 patients.


Subject(s)
COVID-19 , Male , Female , Humans , Aged , Middle Aged , COVID-19/epidemiology , SARS-CoV-2 , Iraq/epidemiology , Retrospective Studies , Comorbidity , Risk Factors , Patient Acuity
2.
Front Immunol ; 14: 1148268, 2023.
Article in English | MEDLINE | ID: covidwho-2317599

ABSTRACT

Introduction: COVID-19 and autoinflammatory diseases, such as Adult-onset Still's Disease (AOSD), are characterized by hyperinflammation, in which it is observed massive production and uncontrolled secretion of pro-inflammatory cytokines. The specialized pro-resolving lipid mediators (SPMs) family is one the most important processes counteracting hyperinflammation inducing tissue repair and homeostasis restoration. Among SPMs, Protectin D1 (PD1) is able to exert antiviral features, at least in animal models. The aim of this study was to compare the transcriptome of peripheral blood mononuclear cells (PBMCs) from patients with AOSD and COVID-19 and to evaluate the role of PD1 on those diseases, especially in modulating macrophages polarization. Methods: This study enrolled patients with AOSD, COVID-19, and healthy donors HDs, undergoing clinical assessment and blood sample collection. Next-generation deep sequencing was performed to identify differences in PBMCs transcripts profiles. Plasma levels of PD1 were assessed by commercial ELISA kits. Monocyte-derived macrophages were polarized into M1 and M2 phenotypes. We analyzed the effect of PD1 on macrophages differentiation. At 10 days, macrophages were analyzed for surface expression of subtypes markers by flow cytometry. Cytokines production was measured in supernatants by Bio-Plex Assays. Results: In the transcriptomes from AOSD patients and COVID-19 patients, genes involved in inflammation, lipid catabolism, and monocytes activation were specifically dysregulated in AOSD and COVID-19 patients when compared to HDs. Patients affected by COVID-19, hospitalized in intensive care unit (ICU), showed higher levels of PD1 when compared to not-ICU hospitalized patients and HDs (ICU COVID-19 vs not-ICU COVID-19, p= 0.02; HDs vs ICU COVID-19, p= 0.0006). PD1 levels were increased in AOSD patients with SS ≥1 compared to patients with SS=0 (p=0.028) and HDs (p=0.048). In vitro treatment with PD1 of monocytes-derived macrophages from AOSD and COVID-19 patients induced a significant increase of M2 polarization vs control (p<0.05). Furthermore, a significant release of IL-10 and MIP-1ß from M2 macrophages was observed when compared to controls (p<0.05). Discussion: PD1 is able to induce pro-resolutory programs in both AOSD and COVID-19 increasing M2 polarization and inducing their activity. In particular, PD1-treated M2 macrophages from AOSD and COVID-19 patients increased the production of IL-10 and enhanced homeostatic restoration through MIP-1ß production.


Subject(s)
COVID-19 , Still's Disease, Adult-Onset , Humans , Transcriptome , Interleukin-10/metabolism , Leukocytes, Mononuclear/metabolism , Chemokine CCL4/metabolism , COVID-19/metabolism , Cytokines/metabolism , Docosahexaenoic Acids/metabolism , Macrophages , Cell Differentiation/genetics
3.
Microorganisms ; 11(4)2023 Mar 31.
Article in English | MEDLINE | ID: covidwho-2303211

ABSTRACT

Since the beginning of the pandemic, the generation of new variants periodically recurs. The XBB.1.5 SARS-CoV-2 variant is one of the most recent. This research was aimed at verifying the potential hazard of this new subvariant. To achieve this objective, we performed a genome-based integrative approach, integrating results from genetic variability/phylodynamics with structural and immunoinformatic analyses to obtain as comprehensive a viewpoint as possible. The Bayesian Skyline Plot (BSP) shows that the viral population size reached the plateau phase on 24 November 2022, and the number of lineages peaked at the same time. The evolutionary rate is relatively low, amounting to 6.9 × 10-4 subs/sites/years. The NTD domain is identical for XBB.1 and XBB.1.5 whereas their RBDs only differ for the mutations at position 486, where the Phe (in the original Wuhan) is replaced by a Ser in XBB and XBB.1, and by a Pro in XBB.1.5. The variant XBB.1.5 seems to spread more slowly than sub-variants that have caused concerns in 2022. The multidisciplinary molecular in-depth analyses on XBB.1.5 performed here does not provide evidence for a particularly high risk of viral expansion. Results indicate that XBB.1.5 does not possess features to become a new, global, public health threat. As of now, in its current molecular make-up, XBB.1.5 does not represent the most dangerous variant.

4.
Diagnostics (Basel, Switzerland) ; 13(5), 2023.
Article in English | EuropePMC | ID: covidwho-2259361

ABSTRACT

Background: Monitoring antibody response following SARS-CoV-2 vaccination is strategic, and neutralizing antibodies represent the gold standard. The neutralizing response to Beta and Omicron VOCs was evaluated versus the gold standard by a new commercial automated assay. Methods: Serum samples from 100 healthcare workers from the Fondazione Policlinico Universitario Campus Biomedico and the Pescara Hospital were collected. IgG levels were determined by chemiluminescent immunoassay (Abbott Laboratories, Wiesbaden, Germany) and serum neutralization assay as the gold standard. Moreover, a new commercial immunoassay, the PETIA test Nab (SGM, Rome, Italy), was used for neutralization evaluation. Statistical analysis was performed with R software, version 3.6.0. Results: Anti-SARS-CoV-2 IgG titers decayed during the first ninety days after the vaccine second dose. The following booster dose significantly (p < 0.001) increased IgG levels. A correlation between IgG expression and neutralizing activity modulation was found with a significant increase after the second and the third booster dose (p < 0.05. Compared to the Beta variant of the virus, the Omicron VOC was associated with a significantly larger quantity of IgG antibodies needed to achieve the same degree of neutralization. The best Nab test cutoff for high neutralization titer (≥1:80) was set for both Beta and Omicron variants. Conclusion: This study correlates vaccine-induced IgG expression and neutralizing activity using a new PETIA assay, suggesting its usefulness for SARS-CoV2 infection management.

5.
Diabetes Metab Res Rev ; 39(3): e3601, 2023 03.
Article in English | MEDLINE | ID: covidwho-2255992

ABSTRACT

INTRODUCTION: Diabetes mellitus worsens the prognosis of SARS-CoV-2 infection, and vaccination has been the major tool for reducing the risk of hospitalisation, and mortality. The primary aim of this study was to evaluate the response to the SARS-CoV-2 vaccine in subjects with diabetes and controls. Differences between type 1 (T1D) and type 2 (T2D) diabetes and clinical determinants of vaccination response were also evaluated. METHODS: 128 subjects with diabetes (60 with T1D and 62 with T2D) and 202 subjects acting as controls who completed a full vaccination cycle with two doses of mRNA vaccine were enroled. People with previous SARS-CoV-2 infection were excluded. Antibodies (Ab) directed against the spike protein of the SARS-CoV-2 were evaluated at one and 6 months after vaccination. RESULTS: In the whole cohort, the Ab level was higher among women than in men (p = 0.011) and negatively correlated with age (rho = -0.155, p = 0.005). Subjects with diabetes showed decreased levels of Ab after one month compared to controls (1217[747-1887]BAU/mL vs. 1477[942-2556]BAU/mL, p = 0.002), even after correction for age and gender (p = 0.002). No difference was found between subjects with T1D and T2D. After 6 months, antibody levels significantly decreased in people with and without diabetes, with no differences between groups, although some subjects were lost at follow-up. In subjects with diabetes, only a significant correlation was found between Ab level and renal function (rho 0.190, p = 0.042). CONCLUSIONS: Both T1D and T2D are associated with a reduced early response to vaccination. The serum concentration of Ab significantly reduced over time in both groups, highlighting the relevance of vaccination boosters independently of the presence of diabetes.


Subject(s)
COVID-19 , Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Male , Female , Humans , Diabetes Mellitus, Type 2/complications , Follow-Up Studies , RNA, Viral , COVID-19 Vaccines , COVID-19/prevention & control , SARS-CoV-2 , Vaccination , Antibodies
6.
Diagnostics (Basel) ; 13(5)2023 Feb 26.
Article in English | MEDLINE | ID: covidwho-2259362

ABSTRACT

BACKGROUND: Monitoring antibody response following SARS-CoV-2 vaccination is strategic, and neutralizing antibodies represent the gold standard. The neutralizing response to Beta and Omicron VOCs was evaluated versus the gold standard by a new commercial automated assay. METHODS: Serum samples from 100 healthcare workers from the Fondazione Policlinico Universitario Campus Biomedico and the Pescara Hospital were collected. IgG levels were determined by chemiluminescent immunoassay (Abbott Laboratories, Wiesbaden, Germany) and serum neutralization assay as the gold standard. Moreover, a new commercial immunoassay, the PETIA test Nab (SGM, Rome, Italy), was used for neutralization evaluation. Statistical analysis was performed with R software, version 3.6.0. RESULTS: Anti-SARS-CoV-2 IgG titers decayed during the first ninety days after the vaccine second dose. The following booster dose significantly (p < 0.001) increased IgG levels. A correlation between IgG expression and neutralizing activity modulation was found with a significant increase after the second and the third booster dose (p < 0.05. Compared to the Beta variant of the virus, the Omicron VOC was associated with a significantly larger quantity of IgG antibodies needed to achieve the same degree of neutralization. The best Nab test cutoff for high neutralization titer (≥1:80) was set for both Beta and Omicron variants. CONCLUSION: This study correlates vaccine-induced IgG expression and neutralizing activity using a new PETIA assay, suggesting its usefulness for SARS-CoV2 infection management.

8.
J Pers Med ; 12(12)2022 Dec 02.
Article in English | MEDLINE | ID: covidwho-2143330

ABSTRACT

Tracking SARS-CoV-2 variants along with vaccinations are fundamental for severe COVID-19 disease prevention. A study was performed that focused on 43 patients with the SARS-CoV-2 infection who were admitted to the Emergency Department. RT-PCR-positive nasopharyngeal samples were sequenced using the MiSeq II system for variant detection. The main reason for Emergency Department admission was COVID-19 (67%), followed by other causes (33%); 51% patients were unvaccinated or vaccinated with a single dose and 49% had completed the vaccination course with two or three doses. Among the vaccinated group, 38% were admitted for COVID-19, versus 94.5% of the unvaccinated group. After admission, 50% of the vaccinated group and 36% of the unvaccinated group were discharged and allowed to go home, and 80% of the unvaccinated had no major comorbidities; 63% needed hospital admission and 5% required a stay in the Intensive Care Unit. Of these, 37% were vaccinated with 3 doses, 11% with two doses, 4% with a single dose, and 48% were unvaccinated. The 70% of the vaccinated patients who were admitted to hospital presented major comorbidities versus 38% of the unvaccinated group. Two unvaccinated patients that needed intensive care had relevant comorbidities and died. Genome sequencing showed the circulation of three omicron and two pure sub-lineages of omicron, including 22 BA.1, 12 BA.1.1, and 7 BA.2. Data showed the SARS-CoV-2 national and international migration patterns and how vaccination was useful for severe COVID-19 disease prevention.

9.
Front Med (Lausanne) ; 9: 929408, 2022.
Article in English | MEDLINE | ID: covidwho-2115318

ABSTRACT

Objective: Coronavirus disease 2019 (COVID-19) is a systemic disease induced by SARS-CoV-2 causing myocardial injury. To date, there are few data on the correlation between mid-regional proAdrenomedullin (MR-proADM) and myocardial injury. The aim of this study was to evaluate whether the association of myocardial injury and elevated mid-regional proAdrenomedullin values could predict mortality of SARS-CoV-2 patients, to offer the best management to COVID-19 patients. Materials and methods: All patients hospitalized for SARS-CoV-2 infection at the COVID-19 Center of the Campus Bio-Medico of Rome University were included between October 2020 and March 2021 and were retrospectively analyzed. Myocardial injury was defined as rising and/or fall of cardiac hs Troponin I values with at least one value above the 99th percentile of the upper reference limit (≥15.6 ng/L in women and ≥34.2 ng/L in men). The primary outcome was 30-day mortality. Secondary outcomes were the comparison of MR-proADM, CRP, ferritin, and PCT as diagnostic and prognostic biomarkers of myocardial injury. Additionally, we analyzed the development of ARDS, the need for ICU transfer, and length of stay (LOS). Results: A total of 161 patients were included in this study. Of these, 58 (36.0%) presented myocardial injury at admission. An MR-proADM value ≥ 1.19 nmol/L was defined as the optimal cut-off to identify patients with myocardial injury (sensitivity 81.0% and specificity 73.5%). A total of 121 patients (75.2%) developed ARDS, which was significantly more frequent among patients with myocardial injury (86.2 vs. 68.9%, p = 0.015). The overall 30-day mortality was 21%. Patients with myocardial injury presented significantly higher mortality compared to those without the same (46.6 vs. 6.8%, p < 0.001). When dividing the entire study population into four groups, based on the presence of myocardial injury and MR-proADM values, those patients with both myocardial injury and MR-proADM ≥ 1.19 nmol/L presented the highest mortality (53.2%, p < 0.001). The combination of myocardial injury and MR-proADM values ≥ 1.19 nmol/L was an independent predictor of death (OR = 7.82, 95% CI = 2.87-21.30; p < 0.001). Conclusion: The study is focused on the correlation between myocardial injury and MR-proADM. Myocardial injury induced by SARS-CoV-2 is strongly associated with high MR-proADM values and mortality.

10.
Pathogens ; 11(9)2022 Sep 04.
Article in English | MEDLINE | ID: covidwho-2010229

ABSTRACT

Since 2020, the COVID-19 pandemic represented an important worldwide burden. Well-structured surveillance by reliable and timely genomic data collection is crucial. In this study, a genomic monitoring analysis of all SARS-CoV-2 positive samples retrieved at the Fondazione Policlinico Universitario Campus Bio-Medico, in Rome, Italy, between December 2021 and June 2022, was performed. Two hundred and seventy-four SARS-CoV-2-positive samples were submitted to viral genomic sequencing by Illumina MiSeqII. Consensus sequences were generated by de novo assembling using the iVar tool and deposited on the GISAID database. Lineage assignment was performed using the Pangolin lineage classification. Sequences were aligned using ViralMSA and maximum-likelihood phylogenetic analysis was performed by IQ-TREE2. TreeTime tool was used to obtain dated trees. Our genomic monitoring revealed that starting from December 2021, all Omicron sub-lineages (BA.1, BA.2, BA.3, BA.4, and BA.5) were circulating, although BA.1 was still the one with the highest prevalence thought time in this early period. Phylogeny revealed that Omicron isolates were scattered throughout the trees, suggesting multiple independent viral introductions following national and international human mobility. This data represents a sort of thermometer of what happened from July 2021 to June 2022 in Italy. Genomic monitoring of the circulating variants should be encouraged considering that SARS-CoV-2 variants or sub-variants emerged stochastically and unexpectedly.

11.
J Med Virol ; 94(4): 1689-1692, 2022 04.
Article in English | MEDLINE | ID: covidwho-1718387

ABSTRACT

The appearance of emerging variants of SARS-CoV-2 carrying mutations into the spike protein has recently raised concern with respect to tracking their transmission and mitigating the impact in the evolving pandemic across countries. AY.4.2, a recently detected Delta variant sublineage, is considered a new variant under investigation (VUI) as it carries specific genetic signatures present in the spike protein, called Y145H and A222V. Here, using genomic epidemiology, we provide the first preliminary insight regarding the circulation of this emerging VUI in Italy.


Subject(s)
COVID-19/epidemiology , Genome, Viral/genetics , SARS-CoV-2/genetics , Adolescent , Adult , Aged , COVID-19/virology , Child , Female , Genomics , Humans , Italy/epidemiology , Male , Middle Aged , Molecular Epidemiology , Mutation , Phylogeny , RNA, Viral/genetics , SARS-CoV-2/isolation & purification , Young Adult
13.
Front Public Health ; 9: 735601, 2021.
Article in English | MEDLINE | ID: covidwho-1581127

ABSTRACT

Despite the "migrants and COVID-19" topic has been neglected since felt marginal concerning other aspects of the SARS-CoV-2 pandemic, it represents a relevant public health issue in the European countries. This report describes COVID-19 containment strategies adopted in a large Italian reception center hosting recently arrived asylum-seeker migrants. Risk assessment and prevention measures adopted were described. Geo-spatial epidemiological analysis of the outbreak was reported. Significant gaps in the knowledge of self-protection measures from contagious diseases and in the perception of the pandemic risk were observed in migrants; health promotion activities, targeted to remove cultural barriers and improve behaviors appropriate to individual protection, were able to fulfill this gap. In low-resource settings, especially in closed communities, the implementation of social distancing strategies, the systematic use of individual protection devices, and active syndromic surveillance are essential tools to limit the risk of outbreaks. In the event of an outbreak, it is relevant to rapidly activate containment procedures based on systematic screening, isolation, and quarantine, taking into consideration the limits of tracing contacts within a closed community. Not being able to trace certain contacts, the geo-spatial epidemiological analysis of cases distribution could be key in the management of the outbreak. Interestingly, positive cases identified in our facility were all clinically pauci-symptomatic or asymptomatic. Dedicated strategies are needed to minimize the chance of SARS-CoV-2 transmission in a limited space such as reception centers and a vulnerable population such as migrants.


Subject(s)
COVID-19 , Transients and Migrants , Developing Countries , Europe , Humans , SARS-CoV-2
14.
Int J Environ Res Public Health ; 19(1)2021 12 29.
Article in English | MEDLINE | ID: covidwho-1580792

ABSTRACT

BACKGROUND: The contamination of ambulances with pathogenic agents represents a potential threat for the public health, not only for common pathogens but also for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The aim of this project was to exploits the germicidal effect of the UVC radiation at 254 nm to sanitize the patient's compartment of ambulances with an advanced UltraViolet SANitizing System (UV-SAN) and assess its relevance for avoiding the spread of COVID-19 and other drug resistant pathogens. METHODS: The system is equipped with UVC lamps that are activated when the ambulance compartment is empty and sanitize the environment in less than 15 min. An Ozone sensor continuously monitors the gas concentration, ensuring it does not exceed threshold value harmful for patients and operators' health. The system is relying on GNSS data and a satellite communication link, which allow to monitor and record traceability (when, where and what) of all the sanitation operations performed. This information is real-time monitored from a dedicated web-application. RESULTS: UVC irradiation efficiently reduced SARS-CoV-2 virus titer (>99.99%), on inanimate surfaces such as plastic, stainless steel or rubber, with doses ranging from 5.5 to 24.8 mJ/cm2 and the UV-SAN system is effective against multi drug resistant (MDR) bacteria up to >99.99%, after 10 to 30 min of irradiation. CONCLUSIONS: UV-SAN can provide rapid, efficient and sustainable sanitization procedures of ambulances.


Subject(s)
Ambulances , COVID-19 , Disinfection , Humans , SARS-CoV-2 , Ultraviolet Rays
15.
J Med Virol ; 93(12): 6551-6556, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1530181

ABSTRACT

Lineage B.1.617+, also known as G/452R.V3 and now denoted by WHO with the Greek letters δ and κ, is a recently described SARS-CoV-2 variant under investigation first identified in October 2020 in India. As of May 2021, three sublineages labeled as B.1.617.1 (κ), B.1.617.2 (δ), and B.1.617.3 have been already identified, and their potential impact on the current pandemic is being studied. This variant has 13 amino acid changes, three in its spike protein, which are currently of particular concern: E484Q, L452R, and P681R. Here, we report a major effect of the mutations characterizing this lineage, represented by a marked alteration of the surface electrostatic potential (EP) of the receptor-binding domain (RBD) of the spike protein. Enhanced RBD-EP is particularly noticeable in the B.1.617.2 (δ) sublineage, which shows multiple replacements of neutral or negatively charged amino acids with positively charged amino acids. We here hypothesize that this EP change can favor the interaction between the B.1.617+ RBD and the negatively charged ACE2, thus conferring a potential increase in the virus transmission.


Subject(s)
COVID-19/virology , SARS-CoV-2/pathogenicity , COVID-19/transmission , Humans , Mutation , Protein Structure, Tertiary , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Static Electricity
16.
J Med Virol ; 93(12): 6479-6485, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1530178

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China in early December 2019 has rapidly widespread worldwide. Over the course of the pandemic, due to the advance of whole-genome sequencing technologies, an unprecedented number of genomes have been generated, providing both invaluable insights into the ongoing evolution and epidemiology of the virus and allowing the identification of hundreds of circulating genetic variants during the pandemic. In recent months variants of SARS-CoV-2 that have an increased number of mutations on the Spike protein have brought concern all over the world. These have been called "variants of concerns" (VOCs), and/or "variants of interests" (VOIs) as it has been suggested that their genome mutations might impact transmission, immune control, and virulence. Tracking the spread of emerging SARS-CoV-2 variants is crucial to inform public health efforts and control the ongoing pandemic. In this review, a concise characterization of the SARS-CoV-2 mutational patterns of the main VOCs and VOIs circulating and cocirculating worldwide has been presented to determine the magnitude of the SARS-CoV-2 threat to better understand the virus genetic diversity and its potential impact on vaccination strategy.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , COVID-19 Vaccines/immunology , China/epidemiology , Evolution, Molecular , Genome, Viral/genetics , Humans , Mutation , Mutation Rate , Phylogeny , Spike Glycoprotein, Coronavirus/immunology , Whole Genome Sequencing
17.
J Med Virol ; 93(10): 5924-5930, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1432426

ABSTRACT

The introduction of trained sniffer dogs for COVID-19 detection could be an opportunity, as previously described for other diseases. Dogs could be trained to detect volatile organic compounds (VOCs), the whiff of COVID-19. Dogs involved in the study were three, one male and two females from different breeds, Black German Shepherd, German Shepherd, and Dutch Shepherd. The training was performed using sweat samples from SARS-CoV2 positive patients and from SARS-Cov2 free patients admitted at the University Hospital Campus Bio-medico of Rome. Gauze with sweat was collected in a glass jar with a metal top and put in metal boxes used for dog training. The dog training protocol was performed in two phases: the olfactory conditioning and the olfactory discrimination research. The training planning was focused on the switch moment for the sniffer dog, the moment when the dog was able to identify VOCs specific for COVID-19. At this time, the dog was able to identify VOCs specific for COVID-19 with significant reliability, in terms of the number of correct versus incorrect (p < 0.0001) reporting. In conclusion, this protocol could provide a useful tool for sniffer dogs' training and their introduction in a mass screening context. It could be cheaper and faster than a conventional testing method.


Subject(s)
COVID-19/diagnosis , Learning/physiology , Smell/physiology , Working Dogs/physiology , Animals , COVID-19/pathology , Dogs , Female , Humans , Male , Middle Aged , Reproducibility of Results , SARS-CoV-2/isolation & purification , Sweat/chemistry , Volatile Organic Compounds/analysis , Volatile Organic Compounds/isolation & purification
18.
Commun Biol ; 4(1): 489, 2021 04 21.
Article in English | MEDLINE | ID: covidwho-1387493

ABSTRACT

We investigated SARS-CoV-2 transmission dynamics in Italy, one of the countries hit hardest by the pandemic, using phylodynamic analysis of viral genetic and epidemiological data. We observed the co-circulation of multiple SARS-CoV-2 lineages over time, which were linked to multiple importations and characterized by large transmission clusters concomitant with a high number of infections. Subsequent implementation of a three-phase nationwide lockdown strategy greatly reduced infection numbers and hospitalizations. Yet we present evidence of sustained viral spread among sporadic clusters acting as "hidden reservoirs" during summer 2020. Mathematical modelling shows that increased mobility among residents eventually catalyzed the coalescence of such clusters, thus driving up the number of infections and initiating a new epidemic wave. Our results suggest that the efficacy of public health interventions is, ultimately, limited by the size and structure of epidemic reservoirs, which may warrant prioritization during vaccine deployment.


Subject(s)
COVID-19/transmission , Communicable Disease Control/methods , Genome, Viral/genetics , Mutation , Public Health/methods , SARS-CoV-2/genetics , COVID-19/epidemiology , COVID-19/virology , Geography , Humans , Italy/epidemiology , Pandemics , Phylogeny , Public Health/trends , SARS-CoV-2/classification , SARS-CoV-2/physiology
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