The breadth of the neutralizing antibody response to original SARS-CoV-2 infection is linked to the presence of Long COVID symptoms

The associations between longitudinal dynamics and the breadth of SARS-CoV-2 neutralizing antibody (nAb) response with various Long COVID phenotypes before 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. We measured longitudinal neutralizing and cross-neutralizing antibody responses to pre- and post-SARS-CoV-2 Omicron variants in participants infected early in the COVID-19 pandemic, before widespread rollout of SARS-CoV-2 vaccines. Cross-sectional regression models adjusted for 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, as well as Long COVID phenotypes. We identified several novel relationships between SARS-CoV-2 antibody neutralization and the presence of Long COVID symptoms. Specifically, we show that, although nAb responses to the original, infecting strain of SARS-CoV-2 were not associated with Long COVID 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 Long COVID and with persistent gastrointestinal and neurological symptoms. Longitudinal modeling demonstrated significant associations in the overall levels and rates of decay of neutralization capacity with Long COVID phenotypes. A higher proportion of participants had antibodies capable of neutralizing Omicron BA.5 compared with BA.1 or XBB.1.5 variants. Our findings suggest that relationships between various immune responses and Long COVID are likely complex but may involve the breadth of antibody neutralization responses.

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

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.

Non-Pharmacological Therapies for Post-Viral Syndromes, Including Long COVID: A Systematic Review

BACKGROUND

Post-viral syndromes (PVS), including Long COVID, are symptoms sustained from weeks to years following an acute viral infection. Non-pharmacological treatments for these symptoms are poorly understood. This review summarises the evidence for the effectiveness of non-pharmacological treatments for PVS.

METHODS

We conducted a systematic review to evaluate the effectiveness of non-pharmacological interventions for PVS, as compared to either standard care, alternative non-pharmacological therapy, or placebo. The outcomes of interest were changes in symptoms, exercise capacity, quality of life (including mental health and wellbeing), and work capability. We searched five databases (Embase, MEDLINE, PsycINFO, CINAHL, MedRxiv) for randomised controlled trials (RCTs) published between 1 January 2001 to 29 October 2021. The relevant outcome data were extracted, the study quality was appraised using the Cochrane risk-of-bias tool, and the findings were synthesised narratively.

FINDINGS

Overall, five studies of five different interventions (Pilates, music therapy, telerehabilitation, resistance exercise, neuromodulation) met the inclusion criteria. Aside from music-based intervention, all other selected interventions demonstrated some support in the management of PVS in some patients.

INTERPRETATION

In this study, we observed a lack of robust evidence evaluating the non-pharmacological treatments for PVS, including Long COVID. Considering the prevalence of prolonged symptoms following acute viral infections, there is an urgent need for clinical trials evaluating the effectiveness and cost-effectiveness of non-pharmacological treatments for patients with PVS.

REGISTRATION

The study protocol was registered with PROSPERO [CRD42021282074] in October 2021 and published in BMJ Open in 2022.

Post-Viral Fatigue Following SARS-CoV-2 Infection during Pregnancy: A Longitudinal Comparative Study

Studies reported post-COVID-19 fatigue in the general population, but not among pregnant women. Our objectives were to determine prevalence, duration, and risk factors of post-viral fatigue among pregnant women with SARS-CoV-2. This study involved 588 pregnant women with SARS-CoV-2 during pregnancy or delivery in Brazil. Three groups were investigated: G1 (n = 259, symptomatic infection during pregnancy); G2 (n = 131, positive serology at delivery); G3 (n = 198, negative serology at delivery). We applied questionnaires investigating fatigue at determined timepoints after infection for G1, and after delivery for all groups; fatigue prevalence was then determined. Cox regression was used to estimate hazard ratio (HR) and 95% CI of the risk of remaining with fatigue in G1. Overall fatigue prevalence in G1 at six weeks, three months and six months were 40.6%, 33.6%, and 27.8%, respectively. Cumulative risk of remaining with fatigue increased over time, with HR of 1.69 (95% CI: 0.89-3.20) and 2.43 (95% CI: 1.49-3.95) for women with moderate and severe symptoms, respectively. Multivariate analysis showed cough and myalgia as independent risk factors in G1. Fatigue prevalence was significantly higher in G1 compared to G2 and G3. Post-viral fatigue prevalence is higher in women infected during pregnancy; fatigue's risk and duration increased with the severity of infection.

Orthostatic Challenge Causes Distinctive Symptomatic, Hemodynamic and Cognitive Responses in Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Background

Some patients with acute COVID-19 are left with persistent, debilitating fatigue, cognitive impairment ("brain fog"), orthostatic intolerance (OI) and other symptoms ("Long COVID"). Many of the symptoms are like those of other post-infectious fatigue syndromes and may meet criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Common diagnostic laboratory tests are often unrevealing.

Methods

We evaluated whether a simple, standardized, office-based test of OI, the 10-min NASA Lean Test (NLT), would aggravate symptoms and produce objective hemodynamic and cognitive abnormalities, the latter being evaluated by a simple smart phone-based app.

Participants

People with Long COVID (N = 42), ME/CFS (N = 26) and healthy control subjects (N = 20) were studied just before, during, immediately after, 2 and 7 days following completion of the NLT.

Results

The NLT provoked a worsening of symptoms in the two patient groups but not in healthy control subjects, and the severity of all symptoms was similar and significantly worse in the two patient groups than in the control subjects (p < 0.001). In the two patient groups, particularly those with Long COVID, the NLT provoked a marked and progressive narrowing in the pulse pressure. All three cognitive measures of reaction time worsened in the two patient groups immediately following the NLT, compared to the healthy control subjects, particularly in the Procedural Reaction Time (p < 0.01).

Conclusions

A test of orthostatic stress easily performed in an office setting reveals different symptomatic, hemodynamic and cognitive abnormalities in people with Long COVID and ME/CFS, compared to healthy control subjects. Thus, an orthostatic challenge easily performed in an office setting, and the use of a smart phone app to assess cognition, can provide objective confirmation of the orthostatic intolerance and brain fog reported by patients with Long COVID and ME/CFS.

Considerations for the Safe Operation of Schools During the Coronavirus Pandemic

During the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, providing safe in-person schooling has been a dynamic process balancing evolving community disease burden, scientific information, and local regulatory requirements with the mandate for education. Considerations include the health risks of SARS-CoV-2 infection and its post-acute sequelae, the impact of remote learning or periods of quarantine on education and well-being of children, and the contribution of schools to viral circulation in the community. The risk for infections that may occur within schools is related to the incidence of SARS-CoV-2 infections within the local community. Thus, persistent suppression of viral circulation in the community through effective public health measures including vaccination is critical to in-person schooling. Evidence suggests that the likelihood of transmission of SARS-CoV-2 within schools can be minimized if mitigation strategies are rationally combined. This article reviews evidence-based approaches and practices for the continual operation of in-person schooling.

Post-COVID-19 Syndrome and the Potential Benefits of Exercise

The coronavirus disease (COVID-19), caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, is leading to unknown and unusual health conditions that are challenging to manage. Post-COVID-19 syndrome is one of those challenges, having become increasingly common as the pandemic evolves. The latest estimates suggest that 10 to 20% of the SARS-CoV-2 patients who undergo an acute symptomatic phase are experiencing effects of the disease beyond 12 weeks after diagnosis. Although research is beginning to examine this new condition, there are still serious concerns about the diagnostic identification, which limits the best therapeutic approach. Exercise programs and physical activity levels are well-known modulators of the clinical manifestations and prognosis in many chronic diseases. This narrative review summarizes the up-to-date evidence on post-COVID-19 syndrome to contribute to a better knowledge of the disease and explains how regular exercise may improve many of these symptoms and could reduce the long-term effects of COVID-19.