From viral democratic genomes to viral wild bunch of quasispecies.

The tremendous majority of RNA genomes from pathogenic viruses analyzed and deposited in databases are consensus or "democratic" genomes. They represent the genomes most frequently found in the clinical samples of patients but do not account for the huge genetic diversity of coexisting genomes, which is better described as quasispecies. A viral quasispecies is defined as the dynamic distribution of nonidentical but closely related mutants, variants, recombinant, or reassortant viral genomes. Viral quasispecies have collective behavior and dynamics and are the subject of internal interactions that comprise interference, complementation, or cooperation. In the setting of SARS-CoV-2 infection, intrahost SARS-CoV-2 genetic diversity was recently notably reported for immunocompromised, chronically infected patients, for patients treated with monoclonal antibodies targeting the viral spike protein, and for different body compartments of a single patient. A question that deserves attention is whether such diversity is generated postinfection from a clonal genome in response to selection pressure or is already present at the time of infection as a quasispecies. In the present review, we summarize the data supporting that hosts are infected by a "wild bunch" of viruses rather than by multiple virions sharing the same genome. Each virion in the "wild bunch" may have different virulence and tissue tropisms. As the number of viruses replicated during host infections is huge, a viral quasispecies at any time of infection is wide and is also influenced by host-specific selection pressure after infection, which accounts for the difficulty in deciphering and predicting the appearance of more fit variants and the evolution of epidemics of novel RNA viruses.

Pericarditis related to post-acute COVID infection: A case report and review of the literature.

Cardiovascular involvement has been described in acute and recovered COVID-19 patients. Here, we present a case of symptomatic pericarditis with persistent symptoms for at least six months after the acute infection and report 66 published cases of pericarditis in discharged COVID patients. Patient mean age ± SD was 49.7 ± 13.3 years, ranging from 15 to 75 years and 57.6% were female. A proportion of 89.4% patients reported at least one comorbidity, with autoimmune and allergic disorders, hypertension and dyslipidaemia, as the most frequent. Only 8.3% of patients experienced severe symptoms of acute COVID-19. The time between acute COVID and pericarditis symptoms varied from 14 to 255 days. Chest pain (90.9%), tachycardia (60.0%) and dyspnoea (38.2%) were the most frequent symptoms in post-acute pericarditis. A proportion of 45.5% and 87% of patients had an abnormal electrocardiogram and abnormal transthoracic ultrasound, respectively. Colchicine combined with non-steroidal anti-inflammatory drug (NSAID) or acetylsalicylic acid (aspirin) were prescribed to 39/54 (72%) patients. Of them, 12 were switched to corticosteroid therapy due to non-response to the first-line treatment. Only 6 patients had persisting symptoms and were considered as non-respondent to therapy.Our report highlights that pericarditis should be suspected in COVID-19 patients with persistent chest pain and dyspnoea when pulmonary function is normal. Treatment with non-steroidal anti-inflammatory and colchicine is usually effective but corticosteroids are sometimes required.

SARS-CoV-2 quasi-species analysis from patients with persistent nasopharyngeal shedding.

At the time of a new and unprecedented viral pandemic, many questions are being asked about the genomic evolution of SARS-CoV-2 and the emergence of different variants, leading to therapeutic and immune evasion and survival of this genetically highly labile RNA virus. The nasopharyngeal persistence of infectious virus beyond 17 days proves its constant interaction with the human immune system and increases the intra-individual mutational possibilities. We performed a prospective high-throughput sequencing study (ARTIC Nanopore) of SARS-CoV-2 from so-called "persistent" patients, comparing them with a non-persistent population, and analyzing the quasi-species present in a single sample at time t. Global intra-individual variability in persistent patients was found to be higher than in controls (mean 5.3%, Standard deviation 0.9 versus 4.6% SD 0.3, respectively, p < 0.001). In the detailed analysis, we found a greater difference between persistent and non-persistent patients with non-severe COVID 19, and between the two groups infected with clade 20A. Furthermore, we found minority N501Y and P681H mutation clouds in all patients, with no significant differences found both groups. The question of the SARS-CoV-2 viral variants' genesis remains to be further investigated, with the need to prevent new viral propagations and their consequences, and quasi-species analysis could be an important key to watch out.

Visual interpretation of brain hypometabolism related to neurological long COVID: a French multicentric experience.

BACKGROUND: This multicentre study aimed to provide a qualitative and consensual description of brain hypometabolism observed through the visual analysis of 18F-FDG PET images of patients with suspected neurological long COVID, regarding the previously reported long-COVID hypometabolic pattern involving hypometabolism in the olfactory bulbs and other limbic/paralimbic regions, as well as in the brainstem and cerebellum. METHODS: From the beginning of August 2021 to the end of October 2021, the brain 18F-FDG PET scans of patients referred for suspected neurological long COVID with positive reverse transcription polymerase chain reaction (RT-PCR) and/or serology tests for SARS-CoV-2 infection were retrospectively reviewed in three French nuclear medicine departments (143 patients; 47.4 years old ± 13.6; 98 women). Experienced nuclear physicians from each department classified brain 18F-FDG PET scans according to the same visual interpretation analysis as being normal, mildly to moderately (or incompletely) affected, or otherwise severely affected within the previously reported long-COVID hypometabolic pattern. RESULTS: On the 143 brain 18F-FDG PET scans performed during this 3-month period, 53% of the scans were visually interpreted as normal, 21% as mildly to moderately or incompletely affected, and 26% as severely affected according to the COVID hypometabolic pattern. On average, PET scans were performed at 10.9 months from symptom onset (± 4.8). Importantly, this specific hypometabolic pattern was similarly identified in the three nuclear medicine departments. Typical illustrative examples are provided to help nuclear physicians interpret long-COVID profiles. CONCLUSION: The proposed PET metabolic pattern is easily identified upon visual interpretation in clinical routine for approximately one half of patients with suspected neurological long COVID, requiring special consideration for frontobasal paramedian regions, the brainstem and the cerebellum, and certainly further adapted follow-up and medical care, while the second half of patients have normal brain PET metabolism on average 10.9 months from symptom onset.

Clinical patterns of somatic symptoms in patients suffering from post-acute long COVID: a systematic review.

BACKGROUND: Long COVID-19 may affect patients after hospital discharge. AIMS: This study aims to describe the burden of the long-term persistence of clinical symptoms in COVID-19 patients. METHODS: We conducted a systematic review by using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline. The PubMed and Google Scholar databases were searched for studies that included information on the prevalence of somatic clinical symptoms lasting at least 4 weeks after the onset of a PCR- or serology-confirmed diagnosis of COVID-19. The prevalence of persisting clinical symptoms was assessed and risk factors were described when investigated. Psychological symptoms and cognitive disorders were not evaluated in this study. RESULTS: Thirty-seven articles met the inclusion criteria. Eighteen studies involved in-patients only with a duration of follow-up of either less than 12 weeks, 12 weeks to 6 months, or more. In these studies, fatigue (16-64%), dyspnea (15-61%), cough (2-59%), arthralgia (8-55%), and thoracic pain (5-62%) were the most frequent persisting symptoms. In nineteen studies conducted in a majority of out-patients, the persistence of these symptoms was lower and 3% to 74% of patients reported prolonged smell and taste disorders. The main risk factors for persisting symptoms were being female, older, having comorbidities and severity at the acute phase of the disease. CONCLUSION: COVID-19 patients should have access to dedicated multidisciplinary healthcare allowing a holistic approach. Effective outpatient care for patients with long-COVID-19 requires coordination across multiple sub-specialties, which can be proposed in specialized post-COVID units.

Spreading of a new SARS-CoV-2 N501Y spike variant in a new lineage.

OBJECTIVES: Surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomic epidemiology led us to detect several variants since summer 2020. We report the recent spread of a new SARS-CoV-2 spike 501Y variant. METHODS: SARS-CoV-2 sequences obtained from human nasopharyngeal samples by Illumina next-generation sequencing were analysed using Nextclade and an in-house Python script and were compared using BLASTn to the GISAID database. Phylogeny was investigated using the IQ-TREE software. RESULTS: We identified that SARS-CoV-2 genomes from four patients diagnosed in our institute harboured a new set of amino acid substitutions including L18F, L452R, N501Y, A653V, H655Y, D796Y, G1219V ± Q677H. These spike N501Y genomes are the first of Nextstrain clade 19B. We obtained partial spike gene sequences of this genotype for an additional 43 patients. All patients infected with this genotype were diagnosed since mid-January 2021. We detected 42 other genomes of this genotype in GISAID, which were obtained from samples collected in December 2020 in four individuals and in 2021 in 38 individuals. The 89 sequences obtained in our institute or other laboratories originated from the Comoros archipelago, western European countries (mostly metropolitan France), Turkey and Nigeria. CONCLUSION: These findings warrant further studies to investigate the spread, epidemiological and clinical features, and sensitivity to immune responses of this variant.

Analysis of SARS-CoV-2 Variants From 24,181 Patients Exemplifies the Role of Globalization and Zoonosis in Pandemics.

After the end of the first epidemic episode of SARS-CoV-2 infections, as cases began to rise again during the summer of 2020, we at IHU Méditerranée Infection in Marseille, France, intensified the genomic surveillance of SARS-CoV-2, and described the first viral variants. In this study, we compared the incidence curves of SARS-CoV-2-associated deaths in different countries and reported the classification of SARS-CoV-2 variants detected in our institute, as well as the kinetics and sources of the infections. We used mortality collected from a COVID-19 data repository for 221 countries. Viral variants were defined based on ≥5 hallmark mutations along the whole genome shared by ≥30 genomes. SARS-CoV-2 genotype was determined for 24,181 patients using next-generation genome and gene sequencing (in 47 and 11% of cases, respectively) or variant-specific qPCR (in 42% of cases). Sixteen variants were identified by analyzing viral genomes from 9,788 SARS-CoV-2-diagnosed patients. Our data show that since the first SARS-CoV-2 epidemic episode in Marseille, importation through travel from abroad was documented for seven of the new variants. In addition, for the B.1.160 variant of Pangolin classification (a.k.a. Marseille-4), we suspect transmission from farm minks. In conclusion, we observed that the successive epidemic peaks of SARS-CoV-2 infections are not linked to rebounds of viral genotypes that are already present but to newly introduced variants. We thus suggest that border control is the best mean of combating this type of introduction, and that intensive control of mink farms is also necessary to prevent the emergence of new variants generated in this animal reservoir.

Chikungunya resurgence in the Maldives and risk for importation via tourists to Europe in 2019-2020: A GeoSentinel case series.

BACKGROUND: Chikungunya virus (CHIKV) is an arthropod-borne virus mainly transmitted in tropical areas by Aedes spp. mosquitoes. It has been responsible for small-to-large outbreaks in temperate areas including southern Europe and North America. Past outbreaks in 2006 on the islands of Maldives, as well as on other islands in the Indian Ocean and in Southeast Asia, demonstrated for the first time the capacity of CHIKV to disseminate through travel and transcontinental commerce, and revealed the major socio-economic impact of CHIKV epidemics. Recently, CHIKV has been circulating in highly touristic areas including the Maldives, where 1736 cases were notified by the Health Protection Agency during 2019. CASE SERIES: Among EuroTravNet/GeoSentinel patient records, eight CHIKV-confirmed cases imported the Maldives to France, Germany, Denmark, Italy and Spain were identified between February 2019 and February 2020; exceeding the total number of CHIKV infections travel-acquired in Maldives reported to this surveillance network during the previous 10 years. CONCLUSIONS: The prevention and control of CHIKV introduction into naïve areas colonised by competent vectors is crucial. CHIKV outbreaks must be detected and reported in a timely manner. This must lead to adapted health information for international travellers and to prompt management of suspected imported cases. Conversely, travellers make for excellent sentinels and increased reports of imported cases might reflect a change in the level of endemicity or even herald an outbreak. Feedback to the local health authorities and matching this with local epidemiological surveillance data may lead to health benefits for the local population.

Rapid viral diagnosis and ambulatory management of suspected COVID-19 cases presenting at the infectious diseases referral hospital in Marseille, France, - January 31st to March 1st, 2020: A respiratory virus snapshot.

BACKGROUND: Rapid virological diagnosis is needed to limit the length of isolation for suspected COVID-19 cases. METHOD: We managed the first 280 patients suspected to have COVID-19 through a rapid care circuit and virological diagnosis in our infectious disease reference hospital in Marseille, France. Rapid viral detection was performed on sputum and nasopharyngeal samples. RESULTS: Over our study period, no SARS-CoV-2 was detected. Results were obtained within approximately 3 h of the arrival of patient samples at the laboratory. Other viral infections were identified in 49% of the patients, with most common pathogens being influenza A and B viruses, rhinovirus, metapneumovirus and common coronaviruses, notably HKU1 and NL63. CONCLUSION: Early recognition of COVID-19 is critical to isolate confirmed cases and prevent further transmission. Early rule-out of COVID-19 allows public health containment measures to be adjusted by reducing the time spent in isolation.

Testing the repatriated for SARS-Cov2: Should laboratory-based quarantine replace traditional quarantine?

BACKGROUND: An ongoing epidemic of respiratory diseases caused by a novel coronavirus (COVID 2019, SARS-CoV2) started in Wuhan, Hubei, in China at the end of December 2019. The French government decided to repatriate the 337 French nationals living in Wuhan and place them in quarantine in their home country. We decided to test them all for SARS-Cov2 twice in order to reduce anxiety among the population and decision-makers. METHODS: We investigated the presence of SARS-CoV-19 in asymptomatic carriers by testing all repatriated patients within the first 24 h of their arrival in France and at day 5. Viral RNA was extracted from pooled nasal and oropharyngeal swab fluids or sputum in the absence of nasal/oropharyngeal swabs. Detection of SARS-CoV-2 RNA was then carried out using several real-time reverse transcription (RT)-PCR assays. RESULTS: We tested 337 passengers at day 0 and day 5. All the tests for SARS-CoV2 were negative. By optimising the sampling process, sending samples sequentially and reducing the time-scale for biological analysis, we were able to test the samples within 5 h (including sampling, shipment and biological tests). CONCLUSION: Optimising our procedures reduces anxiety and reassures the population and decision makers.