Systematic review of the prevalence of Long Covid (preprint)

Background: Long Covid occurs in those infected with SARSCoV2 whose symptoms persist or develop beyond the acute phase. We conducted a systematic review to determine the prevalence of persistent symptoms, functional disability or pathological changes in adults or children at least 12 weeks post-infection. Methods: We searched MEDLINE (Ovid), Embase (OVID), the Cochrane Covid-19 Study register, WHO ICTRP, medRxiv, Cochrane CENTRAL, MEDLINE (PubMed), ClinicalTrials.gov, and the WHO Global research on coronavirus disease (COVID-19) database from 1st January 2020 to 2nd November 2021, limited to publications in English. We included studies with at least 100 participants. Studies where all participants were critically ill were excluded. Articles were screened independently by two reviewers, with disagreements resolved by a third. Long Covid (primary outcome) was extracted as prevalence of at least one symptom or pathology, or prevalence of the most common symptom or pathology, at 12 weeks or later. Heterogeneity was quantified in absolute terms and as a proportion of total variation and explored across pre-defined subgroups (PROSPERO ID CRD42020218351). Findings: In total 120 studies in 130 publications were included. Length of follow-up varied from 12 weeks to over 12 months. Few studies had low risk of bias. All complete and subgroup analyses except one had I2 [≥] 90%, with prevalence of persistent symptoms ranging between 0% and 93%. Studies using routine healthcare records tended to report lower prevalence of persistent symptoms/pathology than self-report. However, studies systematically investigating pathology in all participants at follow up tended to report the highest estimates of all three. Studies of hospitalised cases had generally higher estimates than community-based studies. Interpretation: The way in which Long Covid is defined and measured affects prevalence estimation. Given the widespread nature of SARSCoV2 infection globally, the burden of chronic illness is likely to be substantial even using the most conservative estimates.

Long Covid stigma: estimating burden and validating scale in a UK-based sample (preprint)

Background: Stigma can be experienced as perceived or actual disqualification from social and institutional acceptance on the basis of one or more physical, behavioural or other attributes deemed to be undesirable. Long Covid is a predominantly multisystem condition that occurs in people with a history of SARSCoV2 infection, often resulting in functional disability. Aim: To develop and validate a Long Covid Stigma Scale (LCSS); and to quantify the burden of Long Covid stigma. Design and Setting: Follow-up of a co-produced community-based Long Covid online survey using convenience non-probability sampling. Method: Thirteen questions on stigma were designed to develop the LCSS capturing three domains: enacted (overt experiences of discrimination), internalised (internalising negative associations with Long Covid and accepting them as self-applicable) and anticipated (expectation of bias/poor treatment by others) stigma. Confirmatory factor analysis tested whether LCSS consisted of the three hypothesised domains. Model fit was assessed and prevalence was calculated. Results: 966 UK-based participants responded (888 for stigma questions), with mean age 48 years (SD: 10.7) and 85% female. Factor loadings for enacted stigma were 0.70-0.86, internalised 0.75-0.84, anticipated 0.58-0.87, and model fit was good. The prevalence of experiencing stigma at least 'sometimes' and 'often/always' was 95% and 76% respectively. Anticipated and internalised stigma were more frequently experienced than enacted stigma. Those who reported having a clinical diagnosis of Long Covid had higher stigma prevalence than those without. Conclusion: This study establishes a scale to measure Long Covid stigma and highlights common experiences of stigma in people living with Long Covid.

Characteristics of Long Covid: findings from a social media surve (preprint)

Many people are not recovering for months after being infected with SARS-CoV-2. Long Covid has emerged as a major public health concern that needs defining, quantifying, and describing. We aimed to explore the initial and ongoing symptoms of Long Covid following SARS-CoV-2 infection and describe its impact on daily life in people who were not admitted to hospital during the first two weeks of the illness. We co-produced a survey with people living with Long Covid. We collected the data through an online survey using convenience non-probability sampling, with the survey posted both specifically on Long Covid support groups and generally on social media. The criteria for inclusion were adults with lab-confirmed (PCR or antibody) or suspected COVID-19 managed in the community (non-hospitalised) in the first two weeks of illness. We used agglomerative hierarchical clustering to identify specific symptom clusters, and their demographic and functional correlates. We analysed data from 2550 participants with a median duration of illness of 7.7 months (interquartile range (IQR) 7.4-8.0). The mean age was 46.5 years (standard deviation 11 years) with 82.8% females and 79.9% of participants based in the UK. 89.5% described their health as good, very good or excellent before COVID-19. The most common initial symptoms that persisted were exhaustion, chest pressure/tightness, shortness of breath and headache. Cough, fever, and chills were common initial symptoms that became less prevalent later in the illness, whereas cognitive dysfunction and palpitations became more prevalent later in the illness. 26.5% reported lab-confirmation of infection. The biggest difference in ongoing symptoms between those who reported testing positive and those who did not was loss of smell/taste. Ongoing symptoms affected at least 3 organ systems in 83.5% of participants. Most participants described fluctuating (57.7%) or relapsing symptoms (17.6%). Physical activity, stress and sleep disturbance commonly triggered symptoms. A third (32%) reported they were unable to live alone without any assistance at six weeks from start of illness. 16.9% reported being unable to work solely due to COVID-19 illness. 66.4% reported taking time off sick (median of 60 days, IQR 20, 129). 37.0% reported loss of income due to illness, and 64.4% said they were unable to perform usual activities/duties. Acute systems clustered broadly into two groups: a majority cluster (n=2235, 88%) with cardiopulmonary predominant symptoms, and a minority cluster (n=305, 12%) with multisystem symptoms. Similarly, ongoing symptoms broadly clustered in two groups; a majority cluster (n=2243, 88.8%) exhibiting mainly cardiopulmonary, cognitive symptoms and exhaustion, and a minority cluster (n=283, 11.2%) exhibited more multisystem symptoms. Belonging to the more severe multisystem cluster was associated with more severe functional impact, lower income, younger age, being female, worse baseline health, and inadequate rest in the first two weeks of the illness, with no major differences in the cluster patterns when restricting analysis to the lab-confirmed subgroup. This is an exploratory survey of Long Covid characteristics. Whilst it is important to acknowledge that it is a non-representative population sample, it highlights the heterogeneity of persistent symptoms, and the significant functional impact of prolonged illness following confirmed or suspected SARS-CoV-2 infection. To study prevalence, predictors and prognosis, research is needed in a representative population sample using standardised case definitions (to include those not lab-confirmed in the first pandemic wave).

Symptoms suggestive of COVID-19 in households with and without children: a descriptive survey (preprint)

Background: Exploring transmission and symptoms of COVID-19 in children is vital, given that schools have recently fully reopened. Objectives: This study aimed to characterise the nature and duration of symptoms suggestive of COVID-19 in UK households, and examine whether the symptoms varied between households with and without children and between adults and children from March to May 2020 in the UK. Methods: An online questionnaire posted on social media (Mumsnet, Twitter, Facebook) was used to gather demographic and symptom information within UK households. Results: Results from 508 households (1057 adults and 398 children) were available for analysis. 64.1% of respondent households with children and 59.1% of households without children had adults with symptoms suggestive of COVID-19. The proportion of adults that reported being symptomatic was 46.1% in households with children (and 36.7% in households without children. In 37.8% of households with at least one adult and one child with symptoms, the childs onset of symptoms started before the adult. Of all children, 35.7% experienced symptoms, with almost a quarter experiencing fluctuating symptoms for more than 2 weeks compared to almost half of symptomatic adults. In general, children had a shorter (median 5 days) and milder illness course than adults (median 10 days). Fatigue was the most common symptom in adults (79.7%) and cough was the most common symptom in children (53.5%). Chest tightness, shortness of breath, fatigue, muscle ache and diarrhoea were more common in adults than children, while cough and fever were equally common. Conclusion: Children had shorter and milder illness than adults, but in almost a quarter of children symptoms lasted more than 2 weeks. In over a third of both adult-child symptomatic households, the child was the first to become ill. Child to adult transmission and clinical presentation in children need to be further characterised.