Tag: covid variants

SARS-CoV-2 Reinfections and Long COVID in the Post-Omicron Phase of the Pandemic

Abstract:

We are reviewing the current state of knowledge on the virological and immunological correlates of long COVID, focusing on recent evidence for the possible association between the increasing number of SARS-CoV-2 reinfections and the parallel pandemic of long COVID. The severity of reinfections largely depends on the severity of the initial episode; in turn, this is determined both by a combination of genetic factors, particularly related to the innate immune response, and by the pathogenicity of the specific variant, especially its ability to infect and induce syncytia formation at the lower respiratory tract.

The cumulative risk of long COVID as well as of various cardiac, pulmonary, or neurological complications increases proportionally to the number of SARS-CoV-2 infections, primarily in the elderly. Therefore, the number of long COVID cases is expected to remain high in the future. Reinfections apparently increase the likelihood of long COVID, but less so if they are mild or asymptomatic as in children and adolescents.

Strategies to prevent SARS-CoV-2 reinfections are urgently needed, primarily among older adults who have a higher burden of comorbidities. Follow-up studies using an established case definition and precise diagnostic criteria of long COVID in people with or without reinfection may further elucidate the contribution of SARS-CoV-2 reinfections to the long COVID burden.

Although accumulating evidence supports vaccination, both before and after the SARS-CoV-2 infection, as a preventive strategy to reduce the risk of long COVID, more robust comparative observational studies, including randomized trials, are needed to provide conclusive evidence of the effectiveness of vaccination in preventing or mitigating long COVID in all age groups. Thankfully, answers not only on the prevention, but also on treatment options and rates of recovery from long COVID are gradually starting to emerge.

Source: Boufidou F, Medić S, Lampropoulou V, Siafakas N, Tsakris A, Anastassopoulou C. SARS-CoV-2 Reinfections and Long COVID in the Post-Omicron Phase of the Pandemic. Int J Mol Sci. 2023 Aug 19;24(16):12962. doi: 10.3390/ijms241612962. PMID: 37629143; PMCID: PMC10454552. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10454552/ (Full text)

Differential effects of SARS-CoV-2 variants on central nervous system cells and blood–brain barrier functions

Abstract:

Background: Although mainly causing a respiratory syndrome, numerous neurological symptoms have been identified following of SARS-CoV-2 infection. However, how the virus affects the brain and how the mutations carried by the different variants modulate those neurological symptoms remain unclear.

Methods: We used primary human pericytes, foetal astrocytes, endothelial cells and a microglial cell line to investigate the effect of several SARS-CoV-2 variants of concern or interest on their functional activities. Cells and a 3D blood-brain barrier model were infected with the wild-type form of SARS-CoV-2, Alpha, Beta, Delta, Eta, or Omicron (BA.1) variants at various MOI. Cells and supernatant were used to evaluate cell susceptibility to the virus using a microscopic assay as well as effects of infection on (i) cell metabolic activity using a colorimetric MTS assay; (ii) viral cytopathogenicity using the xCELLigence system; (iii) extracellular glutamate concentration by fluorometric assay; and (iv) modulation of blood-brain barrier permeability.

Results: We demonstrate that productive infection of brain cells is SARS-CoV-2 variant dependent and that all the variants induce stress to CNS cells. The wild-type virus was cytopathic to all cell types except astrocytes, whilst Alpha and Beta variants were only cytopathic for pericytes, and the Omicron variant cytopathic for endothelial cells and pericytes. Lastly wild-type virus increases blood-brain barrier permeability and all variants, except Beta, modulate extracellular glutamate concentration, which can lead to excitotoxicity or altered neurotransmission.

Conclusions: These results suggest that SARS-CoV-2 is neurotropic, with deleterious consequences for the blood-brain barrier integrity and central nervous system cells, which could underlie neurological disorders following SARS-CoV-2 infection.

Source: Proust A, Queval CJ, Harvey R, Adams L, Bennett M, Wilkinson RJ. Differential effects of SARS-CoV-2 variants on central nervous system cells and blood-brain barrier functions. J Neuroinflammation. 2023 Aug 3;20(1):184. doi: 10.1186/s12974-023-02861-3. PMID: 37537664; PMCID: PMC10398935. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10398935/ (Full text)

Precision Medicine for More Oxygen (P4O2)—Study Design and First Results of the Long COVID-19 Extension

Abstract:

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has led to the death of almost 7 million people, however, with a cumulative incidence of 0.76 billion, most people survive COVID-19. Several studies indicate that the acute phase of COVID-19 may be followed by persistent symptoms including fatigue, dyspnea, headache, musculoskeletal symptoms, and pulmonary functional-and radiological abnormalities. However, the impact of COVID-19 on long-term health outcomes remains to be elucidated.
Aims: The Precision Medicine for more Oxygen (P4O2) consortium COVID-19 extension aims to identify long COVID patients that are at risk for developing chronic lung disease and furthermore, to identify treatable traits and innovative personalized therapeutic strategies for prevention and treatment. This study aims to describe the study design and first results of the P4O2 COVID-19 cohort.
Methods: The P4O2 COVID-19 study is a prospective multicenter cohort study that includes nested personalized counseling intervention trial. Patients, aged 40–65 years, were recruited from outpatient post-COVID clinics from five hospitals in The Netherlands. During study visits at 3–6 and 12–18 months post-COVID-19, data from medical records, pulmonary function tests, chest computed tomography scans and biological samples were collected and questionnaires were administered. Furthermore, exposome data was collected at the patient’s home and state-of-the-art imaging techniques as well as multi-omics analyses will be performed on collected data.
Results: 95 long COVID patients were enrolled between May 2021 and September 2022. The current study showed persistence of clinical symptoms and signs of pulmonary function test/radiological abnormalities in post-COVID patients at 3–6 months post-COVID. The most commonly reported symptoms included respiratory symptoms (78.9%), neurological symptoms (68.4%) and fatigue (67.4%). Female sex and infection with the Delta, compared with the Beta, SARS-CoV-2 variant were significantly associated with more persisting symptom categories.
Conclusions: The P4O2 COVID-19 study contributes to our understanding of the long-term health impacts of COVID-19. Furthermore, P4O2 COVID-19 can lead to the identification of different phenotypes of long COVID patients, for example those that are at risk for developing chronic lung disease. Understanding the mechanisms behind the different phenotypes and identifying these patients at an early stage can help to develop and optimize prevention and treatment strategies.
Source: Baalbaki N, Blankestijn JM, Abdel-Aziz MI, de Backer J, Bazdar S, Beekers I, Beijers RJHCG, van den Bergh JP, Bloemsma LD, Bogaard HJ, et al. Precision Medicine for More Oxygen (P4O2)—Study Design and First Results of the Long COVID-19 Extension. Journal of Personalized Medicine. 2023; 13(7):1060. https://doi.org/10.3390/jpm13071060 https://www.mdpi.com/2075-4426/13/7/1060 (Full text)

Coronary microvascular health in symptomatic patients with prior COVID-19 infection: an updated analysis

Abstract:

Aims: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with endothelial dysfunction. We aimed to determine the effects of prior coronavirus disease 2019 (COVID-19) on the coronary microvasculature accounting for time from COVID-19, disease severity, SARS-CoV-2 variants, and in subgroups of patients with diabetes and those with no known coronary artery disease.

Methods and results: Cases consisted of patients with previous COVID-19 who had clinically indicated positron emission tomography (PET) imaging and were matched 1:3 on clinical and cardiovascular risk factors to controls having no prior infection. Myocardial flow reserve (MFR) was calculated as the ratio of stress to rest myocardial blood flow (MBF) in mL/min/g of the left ventricle. Comparisons between cases and controls were made for the odds and prevalence of impaired MFR (MFR < 2). We included 271 cases matched to 815 controls (mean ± SD age 65 ± 12 years, 52% men). The median (inter-quartile range) number of days between COVID-19 infection and PET imaging was 174 (58-338) days. Patients with prior COVID-19 had a statistically significant higher odds of MFR <2 (adjusted odds ratio 3.1, 95% confidence interval 2.8-4.25 P < 0.001). Results were similar in clinically meaningful subgroups. The proportion of cases with MFR <2 peaked 6-9 months from imaging with a statistically non-significant downtrend afterwards and was comparable across SARS-CoV-2 variants but increased with increasing severity of infection.

Conclusion: The prevalence of impaired MFR is similar by duration of time from infection up to 1 year and SARS-CoV-2 variants, but significantly differs by severity of infection.

Source: Ahmed AI, Al Rifai M, Alahdab F, Saad JM, Han Y, Alfawara MS, Nayfeh M, Malahfji M, Nabi F, Mahmarian JJ, Cooke JP, Zoghbi WA, Al-Mallah MH. Coronary microvascular health in symptomatic patients with prior COVID-19 infection: an updated analysis. Eur Heart J Cardiovasc Imaging. 2023 May 31:jead118. doi: 10.1093/ehjci/jead118. Epub ahead of print. PMID: 37254693. https://pubmed.ncbi.nlm.nih.gov/37254693/

First study results of the P4O2 long COVID cohort

Abstract:

Introduction: Several studies indicate that the acute phase of COVID-19 may be followed by persistent symptoms. However, the impact of COVID-19 on long-term health outcomes remains to be elucidated.

Aims: The Precision Medicine for more Oxygen (P4O2) COVID-19 study aims to identify long COVID patients that are that are at risk for developing chronic lung disease and to identify treatable traits and innovative personalized therapeutic strategies for prevention and treatment. This study describes the baseline characteristics of the P4O2 COVID-19 cohort.

Methods: Long COVID patients were recruited from 5 different hospitals in The Netherlands at 3-6 months post-COVID. Data from medical records and biological samples were collected, pulmonary function tests and chest computed tomography scans were performed and questionnaires were administered during 2 study visits.

Results: 95 long COVID patients were enrolled between May 2021 and September 2022. Study participants were aged 54.2 years on average and of female sex in 49.5% of all cases. Most patients were hospitalized(89.5%) for COVID-19 with a mean hospital stay duration of 8 days. The current study showed persistence of clinical symptoms and signs of pulmonary function test/radiological abnormalities in long COVID patients(81%). The most frequently reported symptom categories were respiratory(80%) and fatigue(69.5%). Both female sex and infection with the Delta, compared with the Beta, SARS-CoV-2 variant were significantly associated with more persisting symptoms.

Conclusions: The first descriptive results of the P4O2 COVID-19 cohort show that long COVID patients show signs of radiological/functional abnormalities and can suffer from a wide range of persisting symptoms.

Source: N Baalbaki, J Blankestijn, M Abdel-Aziz, J De Backer, S Bazdar, I Beekers, R Beijers, J Van Den Bergh, L Bloemsma, H J Bogaard, J Van Bragt, V Van Den Brink, J P Charbonnier, M Cornelissen, Y Dagelet, E H Davies, A Van Der Does, G Downward, C Van Drunen, D Gach, M Geelhoed, J Glastra, K Golebski, I Heijink, J Holtjer, S Holverda, L Houweling, J Jacobs, R Jonker, R Kos, R Langen, I Van Der Lee, A Leliveld, F Mohamed Hoesein, A Neerincx, L Noij, J Olsson, M Van De Pol, S Pouwels, E Rolink, M Rutgers, H Șahin, D Schaminee, A Schols, L Schuurman, P Skipp, G Slingers, O Smeenk, B Sondermeijer, M Tamarit, I Verkouter, R Vermeulen, R De Vries, E Weersink, M Van De Werken, Y De Wit-Van De Wijck, S Young, E Nossent, A Maitland-Van Der Zee. ERJ Open Research 2023 9: 68; DOI: 10.1183/23120541.LSC-2023.68 https://openres.ersjournals.com/content/9/suppl_10/68

 

Long COVID in Children and Youth After Infection or Reinfection with the Omicron Variant: A Prospective Observational Study

Abstract:

To describe the prevalence of long COVID in children infected for the first time (n=332) or reinfected (n=243) with Omicron variant SARS-CoV-2, compared with test-negative children (n=311). 12-16% infected with Omicron met the research definition of long COVID at 3 and 6 months after infection, with no evidence of difference between cases of first-positive and reinfection (pchi-square=0.17).

Source: Pinto Pereira SM, Mensah A, Nugawela MD, Stephenson T, Ladhani SN, Dalrymple E, Dudley J, McOwat K, Simmons R, Heyman I, Segal T, Semple MG, Xu L, Shafran R; CLoCk Consortium. Long COVID in Children and Youth After Infection or Reinfection with the Omicron Variant: A Prospective Observational Study. J Pediatr. 2023 May 10:113463. doi: 10.1016/j.jpeds.2023.113463. Epub ahead of print. PMID: 37172813; PMCID: PMC10171900. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10171900/ (Full text)

Risk factors for post-COVID-19 condition (Long Covid) in children: a prospective cohort study

Abstract:

Background: Adults and children can develop post-Covid-19 condition (PCC) (also referred to as Long Covid). However, existing evidence is scarce, partly due to a lack of a standardised case definition, short follow up duration, and heterogenous study designs, resulting in wide variation of reported outcomes. The primary aim of this study was to characterise risk factors for PCC and longitudinal rates of recovery in a cohort of children and young people using a standardised protocol.

Methods: We performed a prospective “disease-based” cohort study between 01/02/2020 to 31/10/2022 including children aged 0-18 years old, with a previous diagnosis of Covid-19. Children with microbiologically confirmed SARS-CoV-2 infection, were invited for an in-clinic follow-up assessment at a paediatric post-covid clinic in Rome, Italy, at serial intervals (3-, 6-, 12- and 18-months post-onset). PCC was defined as persistence of otherwise unexplained symptoms for at least three months after initial infection. The statistical association between categorical variables was obtained by Chi-squared tests or Fisher’s exact tests. Multivariable logistic regressions are presented using odds ratios (OR) and 95% confidence interval (CI). Survival analysis was conducted using the Kaplan-Meier method.

Findings: 1243 children were included, median age: 7.5 (4-10.3) years old; 575 (46.3%) were females. Of these, 23% (294/1243) were diagnosed with PCC at three months post-onset. Among the study population, 143 patients remained symptomatic at six months, 38 at 12 months, and 15 at 18 months follow up evaluation. The following risk factors were associated with PCC: >10 years of age (OR 1.23; 95% CI 1.18-1.28), comorbidities (OR 1.68; 95% CI 1.14-2.50), and hospitalisation during the acute phase (OR 4.80; 95%CI 1.91-12.1). Using multivariable logistic regression, compared to the Omicron variant, all other variants were significantly associated with PCC at 3 and 6 months. At least one dose of vaccine was associated with a reduced, but not statistically significant risk of developing PCC.

Interpretation: In our study, acute-phase hospitalisation, pre-existing comorbidity, being infected with pre-Omicron variants and older age were associated with a higher risk of developing PCC. Most children recovered over time, but one-in-twenty of those with PCC at three months reported persistent symptoms 18 months post-Sars-CoV-2 infection. Omicron infection was associated with shorter recovery times. We did not find a strong protective effect of vaccination on PCC development. Although our cohort cannot be translated to all Italian children with PCC as more nationwide studies are needed, our findings highlight the need of new strategies to prevent and treat pediatric PCC are needed.

Funding: This study has been funded by Pfizer non-competitive grant, granted to DB (# 65925795).

Source: Morello R, Mariani F, Mastrantoni L, De Rose C, Zampino G, Munblit D, Sigfrid L, Valentini P, Buonsenso D. Risk factors for post-COVID-19 condition (Long Covid) in children: a prospective cohort study. EClinicalMedicine. 2023 May;59:101961. doi: 10.1016/j.eclinm.2023.101961. Epub 2023 Apr 14. PMID: 37073325; PMCID: PMC10101848. https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(23)00138-4/fulltext (Full text)

The Breadth of the Neutralizing Antibody Response to Original SARS-CoV-2 Infection is Linked to the Presence of Long COVID Symptoms

Abstract:

Background: The associations between longitudinal dynamics and the breadth of SARS-CoV-2 neutralizing antibody response with various Long COVID (LC) phenotypes prior to vaccination are not known. The capacity of antibodies to cross neutralize a variety of viral variants may be associated with ongoing pathology and persistent symptoms.

Methods: We measured longitudinal neutralizing and cross-neutralizing antibody responses to pre- and post-SARS-CoV-2 Omicron variants in participants infected during the early waves of the COVID-19 pandemic, prior to wide-spread rollout of SARS-CoV-2 vaccines. Cross sectional regression models adjusted for various clinical covariates and longitudinal mixed effects models were used to determine the impact of the breadth and rate of decay of neutralizing responses on the development of Long COVID symptoms in general, as well as LC phenotypes.

Results: We identified several novel relationships between SARS-CoV-2 antibody neutralization and the presence of LC symptoms. Specifically, we show that, although neutralizing antibody responses to the original, infecting strain of SARS-CoV-2 were not associated with LC in cross-sectional analyses, cross-neutralization ID50 levels to the Omicron BA.5 variant approximately 4 months following acute infection was independently and significantly associated with greater odds of LC and with persistent gastrointestinal and neurological symptoms. Longitudinal modeling demonstrated significant associations in the overall levels and rates of decay of neutralization capacity with LC phenotypes. A higher proportion of participants had antibodies capable of neutralizing Omicron BA.5 compared with BA.1 or XBB.1.5 variants.

Conclusions: Our findings suggest that relationships between various immune responses and LC are likely complex but may involve the breadth of antibody neutralization responses.

Source: Buck AM, Deitchman AN, Takahashi S, Lu S, Goldberg SA, Hoh R, Williams MC, Kerbleski M, Deveau TM, Munter SE, Lombardo J, Wrin T, Petropoulos CJ, Durstenfeld MS, Hsue PY, Kelly JD, Greenhouse B, Martin JN, Deeks SG, Peluso MJ, Henrich TJ. The Breadth of the Neutralizing Antibody Response to Original SARS-CoV-2 Infection is Linked to the Presence of Long COVID Symptoms. medRxiv [Preprint]. 2023 Mar 31:2023.03.30.23287923. doi: 10.1101/2023.03.30.23287923. PMID: 37034660; PMCID: PMC10081395. https://www.medrxiv.org/content/10.1101/2023.03.30.23287923v1.full-text (Full text)

Fatigue, sleepiness and sleep quality are SARS-CoV-2 variant independent in patients with long COVID symptoms

Abstract:

Acute infections with SARS-CoV-2 variants of concerns (VOCs) differ in clinical presentation. Discrepancies in their long-term sequelae, commonly referred to as long COVID, however, remain to be explored. We retrospectively analyzed data of 287 patients presented at the post-COVID care of the Pulmonology Department, Semmelweis University, Budapest, Hungary, and infected with SARS-CoV-2 during a period of 3 major epidemic waves in Hungary (February-July 2021, VOC: B.1.1.7, Alpha, N = 135; August-December 2021, VOC: B.1.617.2, Delta, N = 89; and January-June 2022, VOC: B.1.1.529, Omicron; N = 63), > 4 weeks after acute COVID-19.

Overall, the ratio of long COVID symptomatic (LC) and asymptomatic (NS) patients was 2:1. Self-reported questionnaires on fatigue (Fatigue Severity Scale, FSS), sleepiness (Epworth Sleepiness Scale, ESS) and sleep quality (Pittsburgh Sleep Quality Index, PSQI) showed higher scores for LC (4.79 ± 0.12, 7.45 ± 0.33 and 7.46 ± 0.27, respectively) than NS patients (2.85 ± 0.16, 5.23 ± 0.32 and 4.26 ± 0.29, respectively; p < 0.05 for all vs. LC). By comparing data of the three waves, mean FSS and PSQI scores of LC patients, but not ESS scores, exceeded the normal range in all, with no significant inter-wave differences.

Considering FSS ≥ 4 and PSQI > 5 cutoff values, LC patients commonly exhibited problematic fatigue (≥ 70%) and poor sleep quality (> 60%) in all three waves. Comparative analysis of PSQI component scores of LC patients identified no significant differences between the three waves.

Our findings highlight the importance of concerted efforts to manage both fatigue and sleep disturbances in long COVID patient care. This multifaceted approach should be followed in all cases infected with either VOCs of SARS-CoV-2.

Source: Percze AR, Nagy A, Polivka L, Barczi E, Czaller I, Kovats Z, Varga JT, Ballai JH, Muller V, Horvath G. Fatigue, sleepiness and sleep quality are SARS-CoV-2 variant independent in patients with long COVID symptoms. Inflammopharmacology. 2023 Apr 5:1–7. doi: 10.1007/s10787-023-01190-4. Epub ahead of print. PMID: 37020055; PMCID: PMC10075170. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10075170/ (Full text)

The original strain of SARS-CoV-2, the Delta variant, and the Omicron variant infect microglia efficiently, in contrast to their inability to infect neurons: Analysis using 2D and 3D cultures

Highlights:

  • None of the SARS-CoV-2 original, delta, or omicron strains can infect neurons.
  • The SARS-CoV-2 original, delta, and omicron strains can infect microglia.
  • The CNS cells differentiated from hiPSCs are useful to investigate the infectivity of the virus.

Abstract:

COVID-19 causes neurological damage, systemic inflammation, and immune cell abnormalities. COVID-19-induced neurological impairment may be caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which directly infects cells of the central nervous system (CNS) and exerts toxic effects. Furthermore, SARS-CoV-2 mutations occur constantly, and it is not well understood how the infectivity of the virus to cells of the CNS changes as the virus mutates.

Few studies have examined whether the infectivity of cells of CNS – neural stem/progenitor cells (NS/PCs), neurons, astrocytes, and microglia – varies among SARS-CoV-2 mutant strains. In this study, therefore, we investigated whether SARS-CoV-2 mutations increase infectivity to CNS cells, including microglia.

Since it was essential to demonstrate the infectivity of the virus to CNS cells in vitro using human cells, we generated cortical neurons, astrocytes, and microglia from human induced pluripotent stem cells (hiPSCs). We added pseudotyped lentiviruses of SARS-CoV-2 to each type of cells, and then we examined their infectivity. We prepared three pseudotyped lentiviruses expressing the S protein of the original strain (the first SARS-CoV-2 discovered in the world), the Delta variant, and the Omicron variant on their envelopes and analyzed differences of their ability to infect CNS cells. We also generated brain organoids and investigated the infectivity of each virus.

The viruses did not infect cortical neurons, astrocytes, or NS/PCs, but microglia were infected by the original, Delta, and Omicron pseudotyped viruses. In addition, DPP4 and CD147, potential core receptors of SARS-CoV-2, were highly expressed in the infected microglia, while DPP4 expression was deficient in cortical neurons, astrocytes, and NS/PCs.

Our results suggest that DPP4, which is also a receptor for Middle East respiratory syndrome-coronavirus (MERS-CoV), may play an essential role in the CNS. Our study is applicable to the validation of the infectivity of viruses that cause various infectious diseases in CNS cells, which are difficult to sample from humans.

Source: Kase Y, Sonn I, Goto M, Murakami R, Sato T, Okano H. The original strain of SARS-CoV-2, the Delta variant, and the Omicron variant infect microglia efficiently, in contrast to their inability to infect neurons: Analysis using 2D and 3D cultures. Exp Neurol. 2023 Mar 11;363:114379. doi: 10.1016/j.expneurol.2023.114379. Epub ahead of print. PMID: 36914084; PMCID: PMC10008041. https://www.sciencedirect.com/science/article/pii/S0014488623000638?via%3Dihub (Full text)